THE EVOLUTION OF MORALITY: TOWARD AN INTERDISCIPLINARY EXPLANATION By Eric William Berling A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Philosophy—Doctor of Philosophy 2019 ABSTRACT THE EVOLUTION OF MORALITY: TOWARD AN INTERDISCIPLINARY EXPLANATION By Eric William Berling Evolutionary insights have radically improved our ability to understand (explain) the natural world around us, including how we understand ourselves and our relationship to the rest of the natural world. For the past century and half, evolutionary arguments have been advanced that have looked to explain human morality as a feature of our biological origins, as a capacity or propensity endowed to us by our evolutionary history. Recent research programs within psychology, ethology, and game theory have purported to explain morality. The prolific efforts of these researchers, concentrated especially over the past two decades, has resulted in an impressive literature about the evolution of morality. It is unclear how, if at all, these research programs fit together into a coherent explanation of morality, though there is a tendency in the literature to presume such a moral synthesis that could connect these research endeavors in a meaningful way. This is the central task I seek to accomplish. First, I look for a reportive account of morality-as-explanandum, to see if there is reason to think that the explanations being proposed by these different research programs are ostensibly aiming to explain the same phenomenon. I find sufficient overlap in how the evolutionary approaches conceive of morality, namely that it is a phenomenon that includes social interactions involving behaviors often relevant to helping and hurting others, and the perception and response to these interactions involves the stimulation of an affective moral sense that is combined with rational cognitive processing and consideration of cultural elements such as values, norms, or expectations of approval or disapproval during moral judgment. While the research programs of evolutionary psychology, ethology, and evolutionary game theory are attempting to explain the same phenomenon when they talk about morality, work remains to demonstrate how the different methodological kinds of explanations could fit together. For those who adopt a unity of science view, there is a tendency to prefer explanatory reductionism or explanatory eliminativism that identifies a preferred mode of explanation and removes others. Rejecting such a tendency, I endorse a pluralistic approach that allows for multiple modes of explanation to contribute to our understanding of the same phenomenon. I detail the kinds of explanation that each of the three evolutionary approaches offers, and then argue that Pennock’s CaSE pragmatic model of causation could be used to demonstrate that, in principle, the explanations of each approach can be integrated. Pluralistically weaving the explanations of each approach together yields a more robust and complete account of the causal web that has produced our biological capacities for morality. Furthermore, beyond just giving a more complete account of the causal web, integrating the approaches also helps to insulate the explanatory claims of each from some its more pressing objections. For instance, while evolutionary psychology is susceptible to critiques of adaptationism, by demonstrating that the behavioral building blocks of the proposed innate psychological intuition can be found in our phylogenetic neighbors gives reason to think that the trait has an adaptive function and has been preserved by selective pressures. Similarly, game theoretic approaches can demonstrate via models that the behavioral tendency is, in fact, adaptive and causally advantageous to reproductive success. ACKNOWLEDGEMENTS It is with extreme gratitude that I express appreciation to the many individuals who helped me along this process. My wife, Chelsea, and my son, Kesson, who were patient, encouraging, and endlessly supportive throughout the process. My parents, Bill and Carol, who nurtured in me a boundless curiosity about the biological world. My mentor, Rob, an exemplar of perseverance, whose expertise and assistance was invaluable to improving my project. The many helpful friends and fellow graduate students who were integral to my development as a philosopher and whose community and company made the journey enjoyable: Chet, Darci, Dave, Mark, and Karen. iv TABLE OF CONTENTS INTRODUCTION .......................................................................................................................... 1 0.1 The Entangled Bank metaphor .............................................................................................. 1 CHAPTER 1: Motivation and Significance .................................................................................... 7 1.1 Motivation of Project ............................................................................................................. 7 1.1.1 Motivation: Why Add a Philosopher to an Already Crowded Sandbox? ....................... 8 1.1.2 Motivation: The Long History of Exploring Human Nature .......................................... 9 1.1.2.1 History: “Pre-Modern” ........................................................................................... 17 1.1.2.1.1 The Problem of Cooperation and the Rise (and Fall?) of Sociobiology .......... 26 1.1.2.2 History: “Contemporary Context” .......................................................................... 30 1.1.2.2.1 Evolutionary Psychology.................................................................................. 30 1.1.2.2.2 Animal Ethology .............................................................................................. 31 1.1.2.2.3 Computational Evolutionary Game Theory ..................................................... 32 1.1.2.2.4 Contemporary Context: Conclusion ................................................................. 32 1.1.3 Motivation: Philosophical Implications ........................................................................ 33 1.1.3.1 Normative and Meta-Ethical Implications .............................................................. 33 1.1.3.2 Philosophy of Science Implications ........................................................................ 35 CHAPTER 2: The Entangled Bank: Morality-as-Explanandum .................................................. 36 2.1 Introduction ......................................................................................................................... 36 2.2 Encountering the Entangled Bank: Two Philosophical Priorities ....................................... 38 2.2.1 Navigating the Disparate Landscape of Evolutionary Explanations of Morality ......... 40 2.2.2 What is Morality? .......................................................................................................... 42 2.2.2.1 Morality-as-Explanandum: The Search for a Reportive Definition ....................... 44 2.2.2.1.1 Morality vis-a-vis Evolutionary History .......................................................... 45 2.2.2.1.2 Morality vis-a-vis Ethology (Animal Behavior) .............................................. 47 2.2.2.1.3 Morality vis-a-vis Evolutionary Psychology .................................................... 49 2.2.2.1.4 Morality vis-a-vis Computational Evolutionary Game Theory........................ 50 2.2.2.2 Reportive Morality, Reported ................................................................................. 51 2.2.2.2.1 Reportive Morality versus Morality vis-a-vis Philosophy ............................... 53 2.2.2.2.1.1 The Focus is Explanations, Not Value Theory........................................... 53 2.2.2.2.1.2 No Philosophical Consensus about the Moral Domain .............................. 55 2.2.2.2.1.3 Biology Might Inform Philosophical Morality .......................................... 57 2.2.2.3 Do (non-human) Animals have Morality? .............................................................. 59 2.3 What Lies Ahead ................................................................................................................. 62 v CHAPTER 3: Surveying the Landscape: Explanations of Morality ............................................ 64 3.1 Introduction ......................................................................................................................... 64 3.2 Games: Victorious Strategies as Explananda ...................................................................... 64 3.3 Animal Ethology: The Rest of the Animal Kingdom .......................................................... 69 3.4 The (Human) Mind: Mental Architecture as Explananda ................................................... 72 3.4.1 Evolutionary Psychology .............................................................................................. 73 3.4.2 Defending Evolutionary Psychology: The Vestigial Threats of Sociobiology ............. 76 3.4.2.1 Ethical Objections: Genetic Determinism .............................................................. 79 3.4.2.2 Methodological Objections: Testability and Adaptationism .................................. 85 3.5 The Entangled Bank: Ready to Ascend ............................................................................... 95 CHAPTER 4: The Way Out: The Integrative Explanation .......................................................... 96 4.1 The Presumed Moral Synthesis ........................................................................................... 97 4.2 Complexity .......................................................................................................................... 98 4.3 Explanations ...................................................................................................................... 100 4.3.1 Explanations in Science .............................................................................................. 101 4.3.1.1 Explanations in Science: Arguments from Laws .................................................. 102 4.3.1.2 Explanations in Science: Causes explain Effects ................................................. 104 4.3.1.2.1 The CaSE Model of Causation: The Twine to Bind....................................... 108 4.4 Applying the CaSE Model to Evolutionary Explanations of Morality ............................. 111 4.5 A CaSE for Interdisciplinarity ........................................................................................... 116 4.5.1 Collaborative Integration Can Strengthen Research against Would-Be Weaknesses 116 4.6 Conclusion ......................................................................................................................... 118 REFERENCES ........................................................................................................................... 122 vi INTRODUCTION This project is concerned with the evolution of morality, particularly modern evolutionary explanations of morality. My perspective is that of a philosopher of science, and I offer a critical philosophical analysis of the multidisciplinary investigations into the evolutionary origins of morality that are currently occurring across a variety of disciplines, including evolutionary psychology, computational evolutionary game theory, and comparative (animal) ethology. 0.1 The Entangled Bank metaphor In the poetic conclusion of On the Origin of Species, Darwin provided his famous ‘tangled bank’ metaphor: It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us. … There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or fixed into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved. (1859/2006, p. 760) For Darwin, the tangled bank, teeming with its rich diversity of life, appeared beautifully complex and messily intertwined, yet all of the organisms inhabiting the bank and their myriad of relationships to one another could be understood through the application of the same set of basic natural principles, including, most importantly, natural selection. For Darwin, then, the biological world and its many beautiful mysteries were not unlike the mythological Gordian Knot. As the tale goes, a hopelessly complex and confusing knot bound an ox cart to a post, and no one could manage to unravel it and free the cart. That was, until Alexander the Great 1 employed a simple, practical solution. Accounts differ as to whether he simply cut the knot with his sword or pulled the linchpin of the yoke free, but the moral of the story is that he solved the problem posed by the Gordian Knot with a simple and ingenious solution. In a similar way, we might say that Darwin’s theory of natural selection provided the elegant solution needed to untangle the tangled bank. I want to borrow from Darwin’s famous “tangled bank” metaphor, and use the metaphor of the Entangled Bank1 to illustrate the problem of how to give an evolutionary explanation of morality. At the moment, we are bogged down at the bottom of the muddy bank, mired by some of the controversial history surrounding past attempts to connect evolutionary insights to human morality, including most notably the projects of evolutionary ethics and (human) sociobiology. Nevertheless, from this murky foundation multiple disciplines are generating a plethora of modern evolutionary research into the origins of morality. Much like the interwoven forms of life packed and nestled onto the bank of a stream, the literature on the evolution of morality is like a complicated, knotted up wall of vegetation. It is not clear how all the twisted vines and branches looming before us relate to one another, or how we might best proceed through them. There are two strategies we might use to navigate our way out of the muddy riverbed as we seek to ascend this Entangled Bank, so can we reach a biological explanation of morality. We might clear the overgrown area by tearing away the invasive parasitic vines that do not belong and pruning what remains to reveal an accessible path forward. In philosophical discussions of scientific explanation, such strategies are represented by the programs of reductionism or eliminativism, which seek to identify one privileged of preferred mode of explanation, 1 In the first edition, Darwin reflects upon an “entangled” bank, but in later editions he adopts the term “tangled” bank. I adopt this “entangled bank” terminology for my current project, to help differentiate from Darwin’s more famously known and oft-cited “tangled bank” metaphor. 2 effectively eliminating others. Alternatively, we might collect the vines and branches before us, weaving them together into a braided rope that is a stronger and sturdier than any of the plants would have provided on their own. Such an approach would be a kind of integrative explanatory pluralism, which is broadly the view that different kinds of explanations about the same phenomenon can combined into an integrated explanation that is better than any of the explanations alone (see Gijsbers, 2016 for an excellent introduction on explanatory pluralism, especially pp. 1-5). While some researchers do endorse the former position of cutting away the research programs that do not belong,2 I believe that overall there is a received view that the various theoretical and empirical projects investigating the evolution of morality are in some way complementary, which I will characterize as the Presumed Moral Synthesis. While such an assumption has given rise to speculation about the possibility of fruitful overlap between the different types of approaches, I believe that this presumption is currently naïve and overly optimistic, and that a rigorous explication and defense is needed if any such synthesis is to succeed. To that end, I attempt to organize the evolutionary explanations of morality being offered by evolutionary psychology, evolutionary game theory, and ethology into an integrated, pluralistic explanatory structure. I provide a more rigorous case for an explanatory pluralism that seeks to integrate together the evolutionary explanations being put forth by evolutionary psychology, evolutionary game theory, and comparative ethology. I argue that, despite its deep complexity and interdisciplinary nature, the evolutionary explanation of morality can be unified under Pennock’s (2006) CaSE Model of causal explanation and understood as a complex causal 2 For instance, there are those who view evolutionary psychology as an unjustifiably problematic field that should be jettisoned. More on this, including a defense of evolutionary psychology, is offered in Chapter 3. 3 how possibly explanation that satisfies the normative standards of scientific explanation. Furthermore, given the complex nature of the phenomena, any robust evolutionary explanation of morality will necessitate just such an integrated pluralistic explanation. My initial task is to collect, collate, and organize the disparate research endeavors that purport to explain morality as a product of biological evolution, and in so doing I offer a review of modern evolutionary attempts to understand human morality which may serve as a helpful road map for anyone curious about the topic. I aim to be as descriptively accurate as possible when presenting and characterizing the empirical and theoretical work being done. In order to assuage critics’ worries that these modern attempts are just wading into the same hopeless conceptual quagmires that have bogged down the long and highly contentious—both scientifically and philosophically—history of attempts to understand morality as part of our nature, the evaluative portion of my project then explores to what extent these modern approaches are meaningfully different from past approaches. My prescriptive task, and the most substantive portion of my project, is to offer an argument for why these research disciplines need to be synthesized into an integrative interdisciplinary research project, even despite their sometimes seemingly disdainful attitude toward one another, and to present a framework detailing what such an interdisciplinary project might entail in practice. The first step toward this goal requires offering the needed philosophical analysis of the explanandum3, or just what exactly we are aiming to explain when we talk about the evolution of “morality.” Despite widespread usage of terms like morality in evolutionary accounts of human nature, little attention has been paid to how scientists in these 3 Here and throughout I use “explanandum” in the general sense, meaning merely the “phenomenon being explained.” Hempel’s D-N Model of scientific explanation (see Chapter 4) utilizes a more technical notion of explananda, wherein they are the conclusions of formal arguments, but that is not the sense in which I use the term here and throughout. 4 different research programs understand the concept. By establishing a clear conception of morality, it becomes easier to structurally connect and integrate the evolutionary explanations that have been offered. If we can integrate the disciplinary approaches, then we may be able to create a more robust explanation that not only satisfies the standards of a causal scientific explanation, but also insulates the broader research program from some objections that otherwise bedevil the disciplinary approaches in isolation. A clear explanandum will also facilitate efforts to draw possible philosophical insights from the evolutionary explanation. If the notion of morality that is being evolutionarily explained is largely compatible with the notion held by an ethicist, as I believe it is, then the evolutionary explanations offered might have important philosophical implications. In my concluding remarks, I will briefly suggest potentially fruitful insights that might be further explored. For instance, I believe that the work being done by evolutionary psychology provides justification for adopting a virtue theory approach to normative ethics, over say a utilitarian or deontological framework. After a clear explanandum has been identified, the second step will be to consider the methodological approaches that purport to explain that explanandum. It is especially crucial that the way in which each approach constructs explanations, especially evolutionary explanations, is understood. Once we have a sense of the explanandum we are after and how the approaches that claim to explain it construct their explanations, the third and final step will be to offer a philosophical account of explanation that justifies integrating these explanatory approaches together, presenting a more robust understanding of the explanandum of morality. Now that we have a roadmap for the overall project, the following chapter provides the motivation for why this project is a worthwhile endeavor. I also offer some clarifications to the 5 scope and focus of my project, provide criteria of success, and give a summary of the overall structure of the argument in the remaining chapters. 6 CHAPTER 1: Motivation and Significance 1.1 Motivation of Project I believe that my project is of potential interest to a variety of audiences for several reasons, which I will explore in the following three sections. First, philosophical insights are direly needed in the current exploration of evolution and the origins of morality. Many important philosophical questions—some fundamental to any such inquiry, such as just what do we mean by “morality”—need to be addressed to help evaluate, strengthen and tighten the current work being offered by scientists, psychologists, and game theorists. Second, the question of human nature and its possible role in understanding human behavior and society is one that has captivated our curiosity for thousands of years, and it has received much attention by evolutionists over the past century and half, often inciting heavily-contentious debates that have entered the public discourse, since unlocking the mysteries of our biological makeup and history promises (or, for some, ominously threatens) to help us understand our very selves and our place in the world. The second section of this chapter traces this history. Finally, if the attempt to provide an evolutionary explanation for a phenomenon as complex as the biological basis of human morality can be achieved—and that is of course an open question—it will have significant philosophical implications. One such example is that illuminating the biological realities of human moral reasoning might provide relevant considerations to ethicists and metaethicists working on value theory. Additionally, if a convincing case can be made for the integrative and interdisciplinary account of casual explanation proposed by this project, it might serve as a useful model for scholars thinking about the explanations of complex phenomena generally. These potential philosophical implications of the project at hand are briefly elaborated in the third section of this chapter. 7 1.1.1 Motivation: Why Add a Philosopher to an Already Crowded Sandbox? One might ask why a philosopher’s input is needed to help with the evolutionary explanation of morality, since the task of providing evolutionary explanations is ultimately a scientific endeavor. There are several reasons to invoke philosophical expertise. First, as Dennett (1995) succinctly reminds us, “there is no such thing as philosophy free science; there is only science whose philosophical baggage has been taken on board without examination” (p. 21). This is especially true in this area of research; few scientific questions have as much philosophical baggage as the question of human nature and its role in human behavior. For instance, in modern evolutionary explanations of human morality the very thing being explained, morality-as-explanandum, is rarely explicated in a satisfactory way. This is potentially problematic, because without a clear working concept for what constitutes morality, it is impossible to evaluate the extent to which explanations that purport to tell us something about the origins of morality are aiming at the same explanandum. This is my primary task for Chapter 2, wherein I unpack and disentangle the ways in which “morality” is used by evolutionists attempting to explain it, and I propose a more clearly explicated concept around which to orient and organize the evolutionary research being done. Second, questions about the nature of empirical research disciplines and their relationships to both the external world and other disciplinary approaches to knowing are fundamentally philosophical, not scientific, questions. Within a discipline, determining the standards for what constitutes a good explanation is a philosophical enterprise about the values inherent to the methodological approach(es) that define the discipline. Similarly, understanding the nature of explanation broadly, especially the interdisciplinary casual explanations of a phenomenon as complex and temporally-deep as evolution, warrants rigorous philosophy of 8 science, concerning theories of explanation. In Chapter 3, I survey the nature of evolutionary explanations as offered by psychology, game theory, and ethology, and then, in Chapter 4, I propose a restructuring of the current empirical and theoretical research being done into an integrated and interdisciplinary explanation that is more robust, better insulated against critiques, and suggestive of future research. Finally, the scientific exploration of the social phenomenon of morality is treading in a philosophically fraught domain. For instance, such research raises significant worries about potential ethical implications, including but not limited to concerns about embracing a notion of biological determinism that threatens moral and political ideals of the utmost importance, such as equality. As I build the case for the modern interdisciplinary explanation in Chapter 4, I pay special attention to these ethical worries, carefully and explicitly noting the limits of such research while also demonstrating how a modern interdisciplinary approach avoids, at least to a large degree, the objections to biological determinism leveled against historical attempts to root morality within our evolutionary history. 1.1.2 Motivation: The Long History of Exploring Human Nature The question of our moral nature has been explored from a variety of perspectives for thousands of years. Mencius, a student of Confucius in the third century B.C., argued for the innate goodness of human nature, believing that concern for the welfare of others was reflexively ingrained within us and extended beyond external self-interested considerations such as the promise of rewards or the threat of punishments (in de Waal, 2006, pp. 49-52). This question has enjoyed relatively sustained attention with a fiercely renewed modern vigor that warrants detailed consideration. Much thought—perhaps too much, according to some critics—has been 9 spent on the question of human nature and its relationship to morality. In many ways, it is a fundamental question about us: just what kinds of creatures are we? In fact, one might wonder why we are still talking about this as if it were an exciting new endeavor, given that Darwin and other contemporaries have already explored the evolutionary basis of morality. If modern efforts are merely reinventing the wheel, skeptics will be eager to dismiss this modern work on the same grounds that have been employed to reject the theses of early evolutionary ethicists, socibiologists, and others. Alternatively, perhaps these modern efforts promise more developed and more careful explanations from which we may even vindicate some of the evolutionists of the past, or at the very least may avoid the pitfalls of earlier attempts. I will briefly trace the historical highlights of this effort to understand morality as an adaptation, which will be helpful later as I demonstrate how researchers are not simply re-inventing the wheel. This serves two purposes. First, it should assuage the worries of any skeptics who may be eager to dismiss the modern surge in evolutionary explanations on morality on the grounds that this lofty project has already failed. Second, by presenting a brief historical analysis of evolutionary explanations of morality, we will be able to situate modern explanations within a historically informed context over the following two chapters. The theory of evolution via natural selection did much to lend new tools to the exploration of human nature. Not surprisingly, the new explanatory framework was applied to morality by many evolutionists, including Darwin himself. While exploring the possibility of a biological basis of morality has been a subject of attention since Darwin’s time, it has recently enjoyed a renewed modern vigor as noted earlier. In fact, one might wonder why we are still talking about the evolution of morality as if it were a new breakthrough. To help appreciate the renewed interest, we can look briefly to the topic’s long history. 10 Attempting to understand human morality as a product of natural selection is far from a new endeavor, and Darwin himself invested a fair amount of ink on the topic in The Descent of Man, and Selection in Relation to Sex (1871/2006). The widespread influence of Darwin’s work, amongst both naturalists and general audiences, spurred exploration in the late 1800s and early 1900s into the question of human nature and the possible biological roots of human morality, including now widely-rejected attempts by evolutionary ethicists and social Darwinists to justify normative ethical principles by appealing to the biological process of natural selection. The question of human nature came back into focus again in the mid-20th century, as researchers attempted to crack the “problem of cooperation” and sought to demonstrate mathematically that natural selection could produce altruistic behaviors. Perhaps most famously, this tradition culminated in a very contentious debate surrounding human sociobiology, a field of inquiry first made prominent by E.O. Wilson in Sociobiology: The New Synthesis (1975/2000), who explored the ways in which evolutionary biology might illuminate our understanding of social behaviors and societal structures of social animals. In his speculative final chapter, Wilson suggested that this “new science” might provide meaningful insights not just into animal societies, but also into humans and human society, which quickly erupted into controversy. The contention around this perceived attempt to “biologicize” ethics was not limited to the halls of academia, but also embroiled the public, especially those who were deeply suspicious of any scientific enterprise that might undermine the ideal of human equality by naturalizing human difference, namely by endorsing a notion of “genetic determinism”4 that roots inescapable human differences within our genes. 4 Of course, whether or not Wilson’s notion of human sociobiology is guilty of this sort of scientific overreach is an important issue, but one we will not explore until later. 11 Nevertheless, despite this long history of controversy, there has been a modern resurgence of attempts to explain human morality as a product of evolution. Many books have been published recently on the topic, often with bold titles like Primates and Philosophers: How Morality Evolved (primatologist Frans de Waal, 206), The Origins of Morality: An Evolutionary Account (psychologist Dennis Krebs, 2011), The Structural Evolution of Morality (philosopher and evolutionary game theorist Jason McKenzie Alexander, 2007), and The Moral Animal (science journalist Robert Wright, 1994). Similarly, when looking at the primary literature,5 there is a veritable cornucopia of articles offering evolutionary perspectives of morality, including research by evolutionary psychologists, game theorists, and animal ethologists, especially primatologists. Each of these disciplines is oriented around its own set of foundational assumptions, research methodologies, and standards of evaluation. As a result, while there is much work being done across these disciplines on the evolutionary origins of morality, the efforts still remain largely disjointed from one another. For anyone interested in the evolution of morality, the breadth6 of recent empirical investigations is certainly daunting, but even more problematic is the issue that the relationship between theses bodies of work is unclear. My central interest is to determine how these different types of explanations—with their different explananda, assumptions, methodologies, and explanatory standards—relate to one another. Are these multidisciplinary efforts competing alternative explanations of the same phenomena of morality, are they explaining entirely different phenomena, or are they interlinked as parts of a complex explanation? 5 Here I use the standard academic sense of primary literature to mean peer-reviewed journals. 6 To say nothing of the depth of research that has occurred within any of these disciplines, which is daunting in its own right. 12 While inquiries into human nature trace back as far as recorded human thought,7 Darwinian evolution lent a powerful new perspective from which to tackle the topic. While Darwin did not originate the idea of biological evolution per se, which was an idea with some support among naturalists at the time, he gave the idea scientific weight by discovering natural selection as a major mechanism that could drive evolutionary change.8 His thorough argument in On the Origin of Species9 (1859/2006) provided a carefully reasoned and meticulously supported account of how evolutionary changes occur across generations within a population. While reproduction introduces offspring that inherit traits from their parent(s) with random variations, selective pressures can favor the more advantageous variations and thus increase the reproductive success of those organisms which possess it. The profoundness and impact of this contribution cannot be understated. Within the biological sciences, the mechanism of natural selection has allowed biological inquiry to make productive use of teleological reasoning, enabling biologists to investigate organismal traits as potential adaptations, as features “designed” by natural selection to serve one or more functions. “Designed” here means that the trait was the result of evolution through natural selection, not designed in the sense that there was any intentional or mindful Designer. To understand a trait— be it an intracellular enzyme or a long plume of brightly colored tail feathers—biologists can ask what adaptive role(s) this trait plays in the biological processes in which it is involved. Theodosius Dobzhansky, speaking to the need to appreciate evolutionary histories at both the 7 For instance, philosophers like Plato and Aristotle explored the question of human nature in the Western tradition, while philosophers like Mencius and Hsun Tzu tackled the topic in the Eastern tradition. 8 Concurrently along with Alfred Russel Wallace’s own independent conclusions, which Wallace had arrived at through his observations in the Malay Archipelago (e.g. Wallace, 1858). 9 More completely, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life, but hereafter I use the short Origin of Species. 13 molecular and organismic levels, famously noted that “nothing makes sense in biology except in the light of evolution” (1964, p. 449), and that such an evolutionary perspective was indispensable in understanding both the unity and diversity of life. Darwinian theory was essential during biology’s Modern Synthesis of the mid Twentieth century, wherein the microscopic and macroscopic fields of biology were largely unified as molecular genetics became integrated with evolutionary organismal biology (see Huxley, 1942). The Darwinian Revolution10 did not just influence the academic efforts of practicing biologists, of course, but also challenged the anthropocentrism that permeated broadly through the dominant religious and political worldviews and had placed humans at the figurative center of the universe. Much like the pre-Copernican worldview placed Earth at the center of the cosmological universe, prior to Darwin most viewed humans as the center of the biological universe, around which all other material life was oriented.11 On this hierarchy, humans were special beings set apart from the rest of the natural world, fundamentally different in kind and not just degree. Influenced by Aristotle’s (350 B.C.E.) own efforts to group animals into a hierarchical ranking (History of Animals, Book I), naturalists and zoologists had continued to organize and rank lifeforms into the scala naturae, or the ladder12 of nature, classically situating humans on a rung above the highest animals but below the lesser divine entities like angels. Humans were separate and superior to the animals, due either to their possession of a mind which separated them entirely from the other animals, creatures that were wholly physical and 10 Revolution here in the full Kuhnian (1962) sense of revolutionary science. 11 Typically, in an instrumental role, serving the dominion of man (androcentrism intended, to reflect the prevailing sexist hierarchy of the times that coincided with the instrumentalist view of nature adopted). 12 Though it is not always conceptualized as a ladder, and has been visualized as vertical chains, stair cases, et cetera. 14 mere automatons, or because the complexity and level of human intelligence separated them from any sort of intelligence (or apparent intelligence) observed in the animals. The Origin of Species was profound because it undermined the clear demarcation that separated humans from nature. While Darwinian evolution embraces the rich ways in which all lifeforms are interconnected and chained together through an evolutionary history and common ancestry, the hierarchy that had been forged by so many into the rigid and discreetly separated links of the ascending scala naturae was undermined. This revolutionary aspect of Darwin’s work has led to new ways of thinking about ourselves and almost all of human inquiry. Julian Huxley notes that Origin of Species “has altered the substance and direction of human thought more profoundly than any other publication of the age of print”13 (in Irvine 1963, p. xviii). Daniel Dennett has declared that Darwinian evolution is “the single best idea anyone has ever had” (1995, p. 21), because it bridges that chasm between what had been two entirely separate domains: the empirical world of bodies and forces and causes on the one hand, and the world of goals and purpose, thought and art on the other. Darwin provided the bridge across the chasm, revealing how the world of purpose arose from a world of mindless matter. Prior to Darwin, the apparent design found in nature, especially in living creatures, was often taken as evidence of a creator. Most famously, Paley’s (1802/2004) teleological argument in the form of his “watchmaker analogy” holds that finding an object of significantly complex functional design, such as an operational pocket watch, suggests that we must reasonably assume that it necessarily had a creator and had not simply always existed as such. Thus, the complex yet functional machinery of plants, animals, and humans constitute evidence of a creator, and as an intentional product of that creator they are at least partially insulated from empirical inquiry 13 Here, of course, Huxley’s “age of print” means the entirety of written human thought and history, and is not intended to be a demarcation between the Age of Print and the Digital Age. 15 and explanation regarding their nature and origin. The process of evolution via natural selection, though, provides an alternative means to understand the apparent design of the natural world, since it functions as a process that designs without mind or intention.14 While one could write entire histories about the various ways in which human thought was radically altered in response to Darwin without retreading the many such histories that already exist, my project is focused in particular on how the theory of Darwinian evolution has led to the scientific exploration and explanation of morality in particular. In the following section, I present a brief historical account for the evolutionary exploration of morality starting with Darwin and spanning through to the modern efforts with which this project is most concerned. During this history, I briefly summarize the major contributions to the idea that our evolutionary history and natural selection can, at least partly, help us understand human morality. During this history, I do not offer evaluation of the work presented, but seek at the moment only to lay out the landscape and infrastructure of the discussion. The purpose of this is three-fold. First, like any history, my efforts here might serve as a useful road map for anyone interested in the topic. Second, historical appreciation of the topic can serve as some motivation for my project. Third, the extent to which understanding our morality requires understanding our biology is an important question that has captivated and sustained an impressive amount of attention over the past century and a half. Finally, and most importantly, laying out the history on this topic will be useful in demonstrating to anyone skeptical of the idea that our moral nature can be explored through the lens of evolutionary biology given the contentious history of the project that the modern efforts are not merely reinventing a flawed wheel. I will show that in several important ways, modern efforts to give 14 For a thorough exploration of this, see Dawkins’ The Blind Watchmaker (1986/1996). 16 evolutionary explanations of morality are at least structurally distinct contributions to the history that avoid some of the pitfalls and criticisms of the historical approaches. This is not to say that modern research on the topic will be immune from any criticisms, but at the very least I believe that the modern approaches must be engaged and tackled on their own merits without simply writing them off entirely for past sins. To this end, the historical account of evolutionary explorations of morality that follows is broken into two sections at the discretion of my own interpretation. First, I summarize the Pre- Modern Context, which begins with Darwin’s (1871/2006) own contributions to the question and traces through the following century until the great “sociobiology debate” of the late 1970s and early 1980s. This marks a highly contentious point in the topic’s history, one that garnered widespread controversy and criticism from not just evolutionary biologists but also the wider public. This substantially cooled interest in the topic. Following this, I then look to briefly survey the Contemporary Context, which reinvigorated interest with the emergence of evolutionary psychology, and includes the more recent efforts of evolutionary psychologists, game theorists, and animal ethologists, especially primatologists. 1.1.2.1 History: “Pre-Modern” While Darwin wrote very little on humans in The Origin of Species, he devoted significant attention to understanding humans as products of natural selection in The Descent of Man, and Selection in Relation to Sex15 (1871/2006). His primary motivation for this book was to defend against the criticism that humans are too different from lower animals to have been gradually developed through the process of natural selection. In order to establish that humans 15 Hereafter simply Descent. 17 are a part of nature and not apart from nature—that the difference is a matter of degree and not kind—Darwin presented his case that despite the readily apparent and significant dissimilarities between humans and animals, even the most extreme of these could have been produced through gradual changes to traits in our ancestors. Darwin needed to demonstrate to his skeptics that “man is variable in body and mind; and that the variations are induced, either directly or indirectly, by the same general causes, and obey the same general laws, as with lower animals” (1871/2006, p. 854). The physical characteristics of humans—what Darwin called the “body”16 above—are a much more straightforward case. One who accepted natural selection as a means of explaining the size and shape of bird beaks or the coloration and markings on moth wings could readily see how similar explanations might apply to the particular physical aspects of humans, such as the relatively small size of human canine teeth (1871/2006, pp. 858-859) or the lack of fur (p. 861). It is the rich mental lives of human beings that Darwin recognized as the most daunting phenomena for which to give an evolutionary explanation. Of all the various mental powers that Darwin considered—including intuition, emotion, love, reason, language, and religion—he specifically focused upon morality as the most daunting challenge, noting that the “moral sense perhaps affords the best and highest distinction between man and the lower animals” (p. 837). Darwin built his naturalistic account of morality over the better part of two chapters in Descent, Chapter III and Chapter V. Ultimately, he aimed to explain how we, as creatures produced by natural selection, became beholden to “that short but imperious word ought, so full 16 It should be noted here that Darwin was not explicitly endorsing any sense of Mind-Body dualism, but rather is offering an account fully compatible with physicalism. 18 of high significance” (p. 817). Why is it that humans feel a particular kind of pull to behave appropriately in moral17 situations? For Darwin, the development of morality must certainly have begun with the fact that humans are social animals. All sociable animals, Darwin noted, from the lowest on the scale all the way up through humans, are guided in part by social instincts such as the satisfaction felt in the presence of group members, the discomfort felt when separated, and the sympathy for others in one’s group (pp. 825-826). These social instincts serve an adaptive function for Darwin—that is they were selected for by natural selection—because they benefit the individuals possessing the traits in the sense that “the individuals which took the greatest pleasure in society would best escape various dangerous; whilst those that cared least for their comrades and lived solitary would perish in greater numbers (p. 823). In this way, Darwin appealed to individual selection in evolutionarily explaining the social instincts, though he later also appealed to the level of group selection, noting that human groups which cohered tightly together through their sociability and morality would be advantaged over groups which were full of “selfish and contentious” people (p. 870). Socialization and cooperation, for Darwin, is adaptive for both the individuals in the group and for the group itself and forms the foundation upon which natural selection can give rise to morality. These social instincts, the most important of which on Darwin’s account is sympathy, form the basis of motivations when acting with members of the individual’s associated group. As the reasoning abilities and mental powers of social animals becomes “higher,18” such as the 17 A substantial elaboration and explication of “morality” follows in Chapter 2, including Darwin’s own interpretation of the word. 18 Darwin certainly used hierarchical language similar to that of the scala naturae discussed earlier, though what Darwin likely meant by “higher” here is merely something akin to “more complex.” 19 ability to form memories and engage in reasoning that consults the past and anticipates future consequences, there is also an opportunity for praise and blame from the associated members to influence action. The social instinct of sympathy, in conjunction with these highly developed mental faculties, then provides the individual with something like a conscience and sense of self- command. Darwin believed that such features are likely present even in dogs who can show great restraint in their behavior by not acting upon immediate impulses to do things that would be gratifying but “disobedient,” like stealing food in the absence of their master (pp. 821-822). The conscience, then, motivates by looking backwards and “inducing a kind of dissatisfaction” ranging from regret to severe remorse, motivating the individual to act differently into the future (p. 829). Darwin believed that this largely accounts for what he called that sense of the “imperious ought”—that “habit of self-command” (p. 829). Darwin certainly allowed for cultural elements to play an important role in human morality as well, noting that language especially allows for the creation of a “secondary guide of conduct” that includes “expressions of the wishes and judgment of the members of the same community” (p. 833). This secondary guide of conduct sometimes reinforces the internal guide of the social instincts but may also at times be in opposition to them. The social instincts, for Darwin, are paramount for distinguishing between the “absurd” cultural guides to conduct, such as merely superstitious customs or religious views, and those that do constitute progress toward a higher morality (p. 834). For Darwin, reason allows increasingly civilized19 groups to extend the moral sense that is rooted in their social instincts—their very nature—to all peoples, not just those in their immediate tribe or community, and even to non-human animals (p. 834). The types of moral norms and moral customs which are at odds with that innately natural moral sense 19 There is certainly a tone of Imperialism in some of Darwin’s language, but I leave the considerations and implications for another time. 20 will always be at risk of falling out of a society’s secondary guides to conduct, presumably, because of an internal tension with and lack of reinforcement from the social instincts. Darwin summarizes his evolutionary account thusly: Finally the social instincts, which no doubt were acquired by man, as by the lower animals, for the good of the community, will from the first have given to him some wish to aid his fellows, and some feeling of sympathy. Such impulses will have served him well at a very early period as a rude rule of right and wrong. But as man gradually advanced in intellectual power and was enabled to trace the more remote consequences of his actions; as he acquired sufficient knowledge to reject baneful customs and superstitions; as he regarded more and more not only the welfare but the happiness of his fellow-men; as from habit, following on beneficial experience, instruction, and example, his sympathies become more tender and widely diffused, so as to extend to the men of all races, to the imbecile, the maimed, and other useless members of society, and finally to the lower animals,—so to would the standard of morality rise higher and higher. (p. 836). Darwin’s effort attempted to firmly cast morality in relation to this “moral sense,” a motivating and instinctive conscience that has been built upon our sympathetic and compassionate social instincts that natural selection made a part of our very nature, and that can be reinforced and expanded with cultural components that augment the satisfactions (or the dissatisfactions) experienced when a person conducts themselves in particular ways. Following the influence of Darwin’s Origin (1859/2006) and Descent of Man (1871/2006), Darwin’s efforts to bridge the chasm between humans and the natural world, moved much of what had been relegated to the spiritual into the potentially empirical, inviting attention and investigation upon many aspects of human life and culture. In particular, some thinkers attempted to go beyond simply giving an account of the origin of moral sentiments, but also sought to construct a system of ethics that provided and justified an account of the good and the principle(s) for ethical conduct. That is, they treated the evolutionary investigation of morality as not just a descriptive enterprise, but also a prescriptive one. Evolutionary ethics is the name by which I will refer to all such approaches, which go beyond simply identifying, 21 describing, or explaining the origin of the biological components of our morality and aim at the justification of an ethical system. Evolution and the process of natural selection provided a tantalizing tool with which to pursue a naturalized ethics, which aligned well with the generally growing naturalism of the Victorian era of the time. Darwin himself flirted to some extent with such a project. In Descent, he endorsed a concept of the social instincts that correlates strongly with the prevailing Victorian virtues, and goes so far as to suggest that a notion of the good might be rooted in the general good, which for him means “the greatest possible number of individuals can be reared in full vigour and health, with all their faculties perfect, under the conditions which they are exposed” (p. 833). Of course, Darwin allows for the influence of the “secondary codes” of conduct that emerge with culture and “higher” “more civilized” societies, which are not necessarily adaptive and can contribute to the construction of an ethical system or ethical code based upon various ethical principles, which might (or perhaps is even likely) to progress to what Darwin calls the “foundation-stone of morality,” which for Darwin is “[t]o do good undo others—to do unto others as ye would they should do unto you” (p. 871). It is of course not coincidental that this principle embodies the Golden Rule largely dominant in prevailing Victorian Christianity and sensibilities. Still, Darwin’s main task was primarily one of explaining the evolutionary origin our moral sentiments, as part of his argument for descent with selection as described above, and the extent to which Darwin desired to provide or defend an ethical system that is justified by evolutionary insights is neither substantial nor of much consequence to his overall project. Victorian contemporaries, however, did take up the charge more thoroughly than Darwin in an effort to connect the biological basis of our morality to a fully elaborated and justified evolutionary ethics. Herbert Spencer (1891), like Darwin, saw an important role for sympathy 22 but endorsed a more holistic and broader notion of evolution that saw it as a progressive process, always moving toward improvement, in not just biological systems but also in psychology, economics, politics, and all other aspects of human society. He wrote: Unquestionably, on the Evolution-Hypothesis, this fixed intuition must have been established by that intercourse with things which, throughout an enormous past, has, directly or indirectly, determined the organization of the nervous system and certain resulting necessities of thought; and the a priori beliefs determined by those necessities differ, from a posteriori beliefs simply in this, that they are products of the experience of innumerable successive individuals instead of the experiences of a single individual.. (1891, pp. 55-56) In this way, Spencer’s sense of evolution—in the broad and general sense as a distinctly progressive process affecting the entirety of creation20—provided not just the origin but also the justification for ethics. For Spencer, then, we are not just (merely) moral creatures capable of moral sentiments, of perceiving situations as moral, and of engaging in moral reasoning, but rather moral creatures that have evolved in a universe that itself contains particular codes of conduct we ought to follow. In a more Darwinian vein, thinkers like William Clifford and Leslie Stephen attempted to develop an evolutionary ethics deduced from and justified by the Darwinian process of biological evolution and the sorts of creatures that such an understanding made us out to be. The goal was to appeal to human nature—namely, a Darwinian conception of human nature—to illuminate and justify the norms governing human action and conduct. Evolutionary biology, on their view, is like the cipher that allows us to look at the complexity of human nature and discover the ethical values that are deeply embedded within it. These projects fell well short of convincingly attaining their goals, in part because even Stephen was forced to conclude that no 20 Creation with a lowercase “c” of course, since part of what Spencer was motivated to do was to give a defense of ethics to replace the dethronement of Divine Command theory, given the move toward naturalism of the Darwinian Revolution. 23 satisfactory account could be provided for why functional behaviors that improved survival of individuals within a group and of groups themselves should be a basis for ethics (see Farber 1994, pp. 36-37). Of course, not all evolutionists endorsed the evolutionary exploration of morality as a means to develop an evolutionary ethics. Perhaps most notably, Huxley (1894/1978), an otherwise staunch supporter of the Darwinian contribution to biology, was skeptical of the endeavor for scientific and political reasons. While Huxley accepted that social instincts likely played an essential role in the adaptive success of humans early in their evolutionary history, he believed that the complexities of modern society and culture made any such social instincts rather moot in discussions of ethics. In this way the “State of Art” of what we might now call cultural evolution has trumped and supplanted the “State of Nature” under which the social emotions were evolved. He notes “[t]hat which lies before the human race is a constant struggle to maintain and improve, in opposition to the State of Nature, the Sate of Art of an organized polity; in which, and by which, man may develop a worthy civilization capable of maintaining and constantly improving itself” (1894/1978, p. 34). Nevertheless, Huxley was firmly interested in and supportive of understanding and explaining the biological basis of morality, as long as that line into evolutionary ethics is not crossed. Human society itself a product of “organic necessity” (p. 28), and he argued that the origins of human morality trace to the parental-sibling emotions that drive behaviors which are others-minded have been broadly expanded through humans’ chameleonesque powers of emotional mimicry, resulting in a behavioral process that is quick and reflexive rather than rational (p. 29). 24 Others, like scientist and philosopher Peter Kroptokin (1903/1978) remained agnostic on the issue evolutionary ethics, while still acknowledging the role an evolutionary insight must play in understanding moral behaviors. He wrote: [t]hat mutual aid is the real foundation of our ethical conceptions seems evident enough. But whatever the opinions as to the first origin of the mutual-aid feeling or instinct may be—whether a biological or a supernatural cause is ascribed to it—we must trace its existence as far back as to the lowest stages of the animal world; and from these stages we can follow its uninterrupted evolution, in opposition to a number of contrary agencies, through all degrees of human development, up to the present. (p. 39) In this way, Kroptokin left open the question of evolutionary ethics, or whether or not appeal to evolutionary processes and human nature alone might justify an ethical system based on mutual aid, while still acknowledging that mutual aid is a driving current within evolution, and one that runs counter to the propensity for self-assertion that also plays a strong role in the evolution of social species. Other contributions to the field present an entirely different look at human nature. While all of the evolutionists considered above emphasized the way in which our evolutionary origins supplied us with a human nature founded largely upon the dispositions to cooperate—be it the “moral sense” or a propensity for “mutual aid” or other reflexive application of others-minded emotions—others saw a much darker biology. Most notably, ethologist Konrad Lorenz (1963/1978) put forth a view that human nature is fundamentally bad. On this view we are creatures that are innately aggressive, antagonistic, and self-interested. The strong motivational disposition of humans, what Lorenz calls a passionate “militant enthusiasm,” (p. 70) can propel them to war and violence and murder with extreme fervor. However, culture can with great effort help steer and direct the militant enthusiasm of people toward better and more noble behaviors, and in that way “can keep in check our other instincts” (p. 74). For Lorenz, then, 25 morality seems to resemble a purely social construct that is created and used to contain and redirect our otherwise immorally disposed human nature.21 1.1.2.1.1 The Problem of Cooperation and the Rise (and Fall?) of Sociobiology Darwin himself astutely acknowledged the problem of cooperation—which will get significant attention from evolutionists considered in this section—by noting that the main challenge to this account is that the most virtuous and selfless individuals would take on risks for their group, risks that often might deprive them of offspring and an opportunity to pass these traits through inheritance (1871/2006, p. 870). Essentially, the challenge is to wonder how altruistic behaviors that disadvantage the performer can be selected for by natural selection, if they give a disadvantage rather an advantage to the performer. While Darwin provides a few cursory speculations on resolving this issue, he does not devote much attention or rigor to the challenge but does appeal generally to group selection and the ways in which groups of altruistic individuals may be advantaged over selfish and disorganized groups. For the most part, the problem of cooperation lies as a dormant threat against the Darwinian enterprise to explain the biological origins of morality until the 1960s. Following the success of the “evolutionary synthesis” in the 1940s that unified genetic and evolutionary approaches in biology, scientists in the 1960s sought to construct rigorous quantitative explanatory model for how heritable altruistic behavior could evolve under natural selection. A general rejection of evolutionary explanations that relied on group selection (Williams 1966, Lewontin 1970) pushed biologists to search for mathematical models that could be used in explaining cooperation with non-kin group members without appeal to group selection 21 This resembles the view that de Waal describes as “The Veneer Theory,” where an immoral (or at least amoral core) of human nature has the thin veneer of morality applied to it by society (see de Waal 2006). 26 (Axelrod and Hamilton 1981, p. 1390). Kin-Selection, or the favoring of altruistic behaviors towards offspring and closely-related kin was not seen as a challenge for evolution generally, because the genetic basis of the altruistic behavior which might disadvantage or even kill the performer were likely to also be present in the closely-related benefactors of the action, and thus would continue with advantage in the population and enjoy reproductive success.22 Special attention was given to the evolution of reciprocal altruism (Trivers, 1971), which laid out a mathematical model for an evolutionarily stable behavior strategy wherein altruistic cooperators could receive a selective advantage by benefiting later from reciprocated cooperative acts. These projects sought to create plausible evolutionary game theory models for how behaviors that were costly to the performer but benefited other non-kin members of the social group could emerge, be positively selected for, and become stable enough to be fixed within the population while resisting invasion from other competitor strategies that would seek to take advantage of the cooperators and reap all of the fitness benefits without any of the cost. While these studies did not claim to explain “morality” explicitly, they laid the groundwork for future projects that would expand the exploration of the evolutionary origins from specific types of cooperative behavior to those which collectively and explicitly include morality. Evolutionary biologist Robert Trivers (1971) explicitly extended his work on genetically-based behavioral rules of reciprocal altruism to speculations about human biology. For many, the mathematical rigor of scientists like Hamilton, Trivers, and Axelrod saved cooperation as a product of Darwinian biology and established it as a genetically-based and adaptive behavior that had been produced and preserved by natural selection. This opened the 22 For a thorough discussion of kin selection, see Dawkins (1979). 27 door again for investigations into human nature as a locus of behavior and contributor to culture, the most influential of which was conducted by E. O. Wilson (1975/2000). While known for his seminal work on hymenoptera and their complex insect societies (1971), E.O. Wilson was catapulted into prominence23 in both the scientific and public imaginations with the publication of Sociobiology: The New Synthesis (1975/2000). Like the evolutionary synthesis in biology a decade and a half earlier that linked the genetic with the evolutionary, Wilson saw “the new synthesis” of sociobiology as connecting evolutionary biology to social behaviors, ultimately an attempt to provide the groundwork for a systematic study of the biological foundations of all social behaviors. One thing Wilson did which distinguishes his position from the mathematically modeled game theoretic work of Hamilton, Axelrod, and Trivers was to reaffirm the legitimacy of group selection (p. 106) as an alternative level of selection upon which natural selection can operate. Another sharp contrast is that Wilson very explicitly believed that insights from evolutionary biology can help inform our understanding of human morality, (infamously) writing that we should “consider the possibility that the time has come for ethics to be removed temporarily from the hands of the philosophers and biologicized” (p. 562),24 and this simple and short claim would launch hundreds of pages of evaluation in the ensuing sociobiology debate. The heated scientific and political debate that surrounded the controversy of this singular claim is well known. It was not Wilson’s effort in the first twenty-five chapters of Sociobiology, wherein he discussed the behaviors and life histories of organisms like ants, mantis shrimp, and 23 For better or worse, as certainly much of the attention he received was negative. 24 Of course, just what Wilson means by this claim would require a deep investigation. The extent to which the investigation of ethics should be biologicized is important, though Wilson’s bluntness in his language here does not help with a nuanced interpretation. In Chapter 3 I consider the “sociobiology debate” in more detail as I defend evolutionary psychology from the major controversies surrounding (human) sociobiology. 28 chimpanzees, that raised the ire of critics, but only the final chapter. Once Wilson extended the evolutionary investigation of social behaviors to humans and human societies, criticisms were fierce. A group of Wilson’s own Harvard colleagues, joined by a few other participants, formed the “Sociobiology Study Group of Science for the People” with the intention of constructing counterarguments against sociobiology (Allen et al. 1975/1978, Sociobiology Study Group 1976)/1978). Protesters disrupted lectures given by Wilson and at one point a demonstrator even poured a pitcher of ice water over his head before he took the podium (Salmon and Crawford 2008, p. 11). This controversy turned sociobiology into a bad word, and the usage of “sociobiology” has nearly vanished from modern biological discussions. After the sociobiology debate, investigations into the biology of human nature greatly cooled off, and this marked the end of the “Pre-Modern Context” of the evolution of morality. Still, as noted earlier, it is important to be aware of this history. The phantoms of this lineage haunt the modern empirical and theoretical evolutionary research enterprises that lie at the heart of the current project. Modern efforts to illuminate the origins of human morality are often charged with just being the “new sociobiology,” and as such dismissively deemed unworthy of serious consideration. For instance, evolutionist Jerry Coyne (2000) writes “[t]he latest deadweight dragging us (evolutionary biology) closer to phrenology is evolutionary psychology, or the science formerly known as sociobiology. If evolutionary biology is a soft science, then evolutionary psychology is its flabby underbelly” (quoted in Gray et al. 2003, pp. 247-248). In Chapter 4, after having outlined the modern efforts to explain the evolution of human morality and presented my case for an interdisciplinary explanation, I will return to the often-fatal criticisms that have been leveled against these historical projects and defend the modern interdisciplinary approach from them. 29 1.1.2.2 History: “Contemporary Context” While the biological roots of morality have long held the attention of naturalists, psychologists, and philosophers, it has received a resurgence in the past two decades on the heels of evolutionary psychology. In the next section, I will briefly review the major modern disciplines that have tackled the evolution of morality, including (1) evolutionary moral psychology, (2) animal ethology, and (3) computational evolutionary game theory. This brief preview of each discipline serves merely to give the reader a sense of the major modern fields of investigations into the evolution of morality with which I my project is interested. In Chapter 3, I will flesh out characterizations of each of these approaches in order to present my positive philosophical contribution in Chapter 4 that argues for an integrative evolutionary explanation of morality that necessarily incorporates insights and research from all of these approaches into a robust causal explanation that satisfies explanatory standards and strengthens the approaches against a variety of possible objections. 1.1.2.2.1 Evolutionary Psychology While the sociobiology debate appeared to cool interest in the natural history of human nature, it was only briefly. The case for a modular mind (Fodor 1983) suggested that some aspects of our brains were functional modules, which facilitated renewed research within evolutionary psychology (see Barkow, Cosmides, and Tooby, 1992) that has continued to investigate how mechanisms within the human brain may have been adaptations shaped by the selective pressures of our (or at least our evolutionary ancestors') past environments. In this way, over the past few decades, human sociobiology has “matured”25 into evolutionary psychology. 25 There is actually quite a bit of disagreement regarding the relationship between human sociobiology and evolutionary psychology. It is commonly taken to be the origin of evolutionary 30 Moral evolutionary psychology26 is a broad interdisciplinary approach, containing the work of psychologists, neuroscientists, cognitive scientists, and other related fields. Recent trends within evolutionary psychology seem to be largely sympathetic (pun intended) to Darwin's own speculations on the moral sense's foundation in sympathy. In evolutionary psychology, explanations of how we make moral judgments maintain that “the building blocks of human morality are emotional” and that the affective, intuitive mechanisms these building blocks comprise have a primacy over moral reasoning processes (Haidt 2007, p. 998). 1.1.2.2.2 Animal Ethology Animal ethologists27 study the natural behavior of (non-human) animals. While the observation and study of animal behavior goes at least as far back as Aristotle, studying animal behavior was integral during the Victorian era for greatly informing the work of Darwin and other naturalists, and has continued steadily since. Recent work in the investigation of animal emotion, cooperation, and sociality has provided for the investigation of moral or proto-moral features of animal societies. Most notably, de Waal’s recent (see 1996; 2006; 2019) work, primarily focused on primates, has explicitly lent much empirical observation and theoretical speculation to the consideration of the evolutionary roots of morality. Observational studies of non-primate animals such as birds (McGowan & Woolfenden, 1989), bats (Wilkinson, 1984), psychology, but it is disputed what aspects, if any, are retained. See my response to this debate in Chapter 3 26 Not all work in evolutionary psychology attempts to look at features of morality (quite a bit does), though from here out I will simply refer to these approaches simply as “evolutionary psychology” rather than “evolutionary moral psychology.” 27 Hereafter simply ethology/ethologists. I included “animal” ethology to clearly emphasize the difference between investigating the behaviors and societies of non-human animals as opposed to human animals. Hereafter, when I reference or talk about “animals” I shall always intend to be speaking about non-human animals. 31 fish (Bshary & Gutter, 2006), insects (Wilson, 1971), and may other species have also contributed to our understanding of cooperation in the animal world. 1.1.2.2.3 Computational Evolutionary Game Theory Another approach to offering evolutionary explanations of morality uses the evolutionary game theoretic approach initially developed in the 1960s (Hamilton 1964, Trivers 1971, Axelrod and Hamilton, 1981) to tackle the problem of cooperation and other morally-relevant social interactions through modern computational modeling of game theory (e.g. Skyrms, 2004; Alexander, 2007). A striking difference from the earlier work is the shift from analyzing biological (genetically-based) evolutionary processes to also modeling the processes of cultural evolution (Alexander 2007, p. 19). This extension of evolutionary processes to incorporate cultural change in some sense builds upon Dawkins' (1976/1989) introduction of the concept of the meme—a bit of information that is culturally transmitted—as both a replicator and unit of selection (pp. 189-201). These agent-based evolutionary game theories model, at least to some degree, the social structure between players in the game, ultimately offering explanations for the emergence and stability of certain strategies for interdependent decisions. 1.1.2.2.4 Contemporary Context: Conclusion This snapshot is brief and simplified, but it offers a basic framework from which I shall greatly elaborate in Chapter 3, wherein I compare these currently prevailing methods for constructing evolutionary explanations of morality to see what explanandum/explananda they explain, what assumptions underlie their methodology. This will facilitate my effort in Chapter 4 to integrate the approaches together into a pluralistic explanation using the CaSE model (Pennock 2006). 32 1.1.3 Motivation: Philosophical Implications In addition to the motivations discussed in the above two sections, this section will explore another motivation for my project. 1.1.3.1 Normative and Meta-Ethical Implications As we further improve our understanding of human morality, there exists the potential that such an understanding might help inform our views about normative ethical theories and meta-ethical positions. This is undoubtedly part of the reason why the quest to illuminate the origins of morality has enjoyed so much attention, both historical and current. But those who would seek to employ such insights from evolutionary science—to “biologicize” ethics as Wilson (1975/2000) so ineloquently put it—must be prepared to for the incredible amount of work needed to avoid the many pitfalls facing such a program. While I am skeptical that much normative insight can be justifiably drawn from understanding the evolutionary origins of morality, others have certainly tried. We have already mentioned the greedy overreach of evolutionary ethicists like Clifford and Stephen who sought to ground a system of ethics upon the foundation of our evolutionary history, but these projects have run afoul of the naturalistic fallacy (Moore, 1903) and have been widely regarded as having failed (Farber, 1994). Nevertheless, more recent explorations into the potential for the descriptive enterprise of evolutionary science to contribute to a normative ethics have been offered. Quintelier, van Speybroeck, and Braeckman (2010) argue that science can, in fact, inform normative ethics in ways that are not fallacious. Harris (2010) has tried to defend a case for how science, neuroscience especially, can tell us something about values, but it has not been met without criticism (e.g. Kaufman, 2012). 33 Similar approaches look to our moral nature to muster support for (or against) different moral epistemologies. For some, the sentimentalism of Hume is vindicated (Haidt, 2007; Pizzaro, 2001) by the prominent role that Darwinian sympathy plays in our moral considerations, as evidenced by the more recent research that reveals the affective ways in which humans process moral judgments. Moreover, if ought implies can, then understanding the capacities of our moral and mental architecture that enables our moral reasoning might weigh favorably for or against expecting burdensome standards of moral reasoning. It has even been suggested, based on what we know about the evolution of our moral psychology, that we should restructure our approaches to moral education so that it is more effective (Lampe, 2012). Still others have looked to the science of evolution to find reasons for endorsing particular metaethical positions. These approaches connect the scientific account of our moral nature, the evolved adaptive product of natural selection that it is, to metaethical inquiries about the nature of morality itself. Some even take the evolution of our morality to be an impetus for in some way rejecting the metaethical notion of morality, using our evolutionary history to justify the adoption of anti-realist positions such as error theory (e.g. Joyce, 2001) and moral relativism (e.g. Mizzoni, 2014). Evaluating the ways in which the evolution of morality can be put to work in normative ethics and metaethics is not within the scope of this current project. Nevertheless, for philosophers and other thinkers who want to inform or perhaps even justify their views about value theory by consulting the evolutionary explanations provided for human morality, my project will be of interest. My efforts toward presenting and defending a more robust evolutionary explanation will strengthen the confidence we should put in the nature of human 34 morality and its evolutionary origins. Thus, such a conception of morality-as-explanandum could better inform or support evolutionary perspectives within value theory. As we increasingly understand the moral creature28 that we are, it may aid our efforts to properly understand human morality. For instance, virtue theory’s emphasis on character formation, reputation, and disposition to do the right thing without the rational consultation of explicit rules and principles is very compatible with the account of human moral judgment outlined by evolutionary psychologists and cognitive scientists. 1.1.3.2 Philosophy of Science Implications As interdisciplinary research increasingly becomes the norm for the natural sciences, philosophers of science must increasingly consider the nature of explanation as it pertains to highly complex systems. Morality, which is both a social and psychological phenomenon, presents perhaps one of the more daunting candidates of scientific explanation, much like language and other aspects of human culture. In interesting ways, this account builds upon other modern efforts to reconceptualize explanation in light of increasingly complex systems (Clark, 1998; Pennock, 2006). Using a CaSE model of causal explanation to construct a more robust evolutionary explanation of morality will not only suggest future pathways for research into the phenomenon itself, but may also provide a framework by which to evaluate and construct explanations of other complex phenomena. 28 “Moral creature” here means simply a creature that possesses the required capacities to engage in moral perceptions and judgments. It does not mean a creature that necessarily behaves in morally “good” ways. 35 CHAPTER 2: The Entangled Bank: Morality-as-Explanandum 2.1 Introduction As noted in the previous chapter, the central task of my project is to develop an account of how the disparate and disjointed flood of current research into the evolution of morality can be unified into a coherent, robust causal explanation. In order to develop such an explanation, it will be critical to consider just what it is that we are aiming to explain. What phenomenon (or, more likely, phenomena) would need to be explained to provide us with an evolutionary account of morality? If morality is not a sufficiently bounded, well defined concept, then it will be difficult if not impossible to identify and explain all of the morally-relevant constituent phenomena that comprise it. Without such an explicated account of morality, strong skepticism regarding any claims to have explained it would be warranted. So, what is morality? To answer the question, one might begin by considering the sorts of situations to which we typically ascribe a moral dimension. There is certainly a wide array of such situations: dividing up a resource, keeping a promise, engaging in sexual activities with kin, causing physical harm to a pet, picking litter out of a waterway, refraining from consuming animals, and many others. To compile an exhaustive list of situations would be impossible, complicated still by the fact that there would not be universal agreement about what the inclusion (or exclusion) of some scenarios. Consider, for instance, the somewhat fashionable practice of “Paying-It-Forward” in the coffee shop drive-thru line, which is when someone pays for the coffee order of upcoming car next in line. Is this a moral scenario? Does the benefactor of a “Paid-Forward” coffee have an 36 obligation to continue the chain, at the risk of being a “ bastard”29 if they do not? Is it a praiseworthy act of kindness,30 or a missed opportunity to actually invest effort and resources into those that need it more than the person buying a high-end coffee beverage? People certainly have a variety of opinions about the practice,31 and there is unlikely to be consensus on whether or not such a social exchange is matter of morality at all. On top of such difficulties, a variety of other factors may be morally relevant, which is to say that they are involved in some important way in the resolution of moral scenarios. These include, but are certainly not limited to: social behaviors, the emergence/stability of particular social norms, the brain architecture that grants the capacity to understand and enforce norms, causal mechanisms within the mind that process moral judgments, emotions, affective states involved in moral deliberation and motivation, or the cognitive machinery to reason about situations. Any attempt to collect and categorize all the types of moral situations and potentially relevant factors would be impossible, given their diversity. To think that such disparate activities all fall under the scope of a unified concept called morality might give someone pause. To fuel this concern, recent work in neuroscience (Parkinson et al., 2011) suggests that separate, distinct neural systems are involved in different types of moral judgments (granting, for the moment, that we can make pragmatic sense of “moral judgments”). In particular, researchers found that different neural pathways are in operation for moral considerations of harm, dishonesty, and disgust. As such, there almost certainly is not a single, unified neural infrastructure that engages the broad set of situations that would commonly be considered (so-called) moral situations. 29 https://www.fastcompany.com/3034747/breaking-a-pay-it-forward-chain-isnt-being-a-cheap- bastard-its-good-economics 30 https://www.coffeecupsandcrayons.com/acts-of-kindness-give-a-cup-of-coffee/ 31 https://www.reddit.com/r/starbucks/comments/5jqkeo/the_drive_thru_pay_it_forward_thing/ 37 In the strongest potential form of this objection, one might even argue that a scientific investigation of morality is an instance of the reification fallacy. Gould (1981/1996) famously dismissed scientific attempts to study intelligence quotients (IQ), in part, on the grounds that the researchers were guilty of the reification fallacy. Treating intelligence as a real characteristic that existed in the world and could be identified and measured (quantified) was entirely misguided, Gould believed, as it was imposing a concept of our abstraction onto reality in a way that does not fit the underlying biology of human brains. One might raise similar doubts about attempts to scientifically investigate morality, if it turns out morality is an irredeemably vague concept that cannot be thrust upon an unreceptive reality. Given such questions and concerns, it will be critical to establish a definition of morality that is reasonably clear and applicable to the external world. Doing so is the central task of the current chapter, and it will provide the conceptual foundation for organizing and orienting the disparate evolutionary explanations of morality into a coherent explanatory framework. 2.2 Encountering the Entangled Bank: Two Philosophical Priorities In the previous chapter, I provided an overview of my project that identified the evolutionary explanation of morality as my focal point of interest. The prospect of an evolutionary explanation of morality is compelling for a variety of reasons, not least of which is that it promises to illuminate human nature and to give us valuable insights into what kind of creatures we are, and perhaps even, what kind of creatures we should be, though this last point would require much effort to convincingly argue. For many, as we have seen, morality is the most distinctly human part of our existence, and as such it has served as a holy grail for evolutionists looking to explain the human condition as well as for philosophers hoping either to 38 construct a naturalistic ethic that successful grounds justification for the “good” in nature or to simply develop an empirically-informed metaethics. Thus, it is not surprising that the past century and a half has seen substantial attention and controversy centered around the natural history of morality. While the “Pre-Modern” investigation lost some steam with the issues surrounding the sociobiology debate, the new millennium has seen a renewed interest and vigor for uncovering the evolutionary origins of morality, as exemplified by the volume of work being put out that focuses an evolutionary lens upon the moral aspects of our lives and the social lives of animals. Work in evolutionary psychology, cognitive science and neuroscience, animal ethology, computational game theory, and biological anthropology produce titles that tout the explanation of morality, its origins, or of some moral component(s) that is(are) nestled within our natural history. Drawing again from the poetic charms of Darwin himself, we might even say that seemingly endless works most beautiful and most wonderful have been and are being written about the evolutionary origins of morality. The “seemingly endless” part of that claim is certainly less contentious than the “most beautiful and most wonderful” portion. While there are lingering blemishes looming over the historical evolutionary explanations of morality (some of which have been noted in Chapter 1) as well as current skepticisms and critiques facing modern approaches, in Chapter 4 I will put forth my conception of an integrated causal explanation of morality and defend it from these past and present challenges. Before we can set out that conception and deal with potential objections, however, there are two important philosophical issues that must take priority: (1) determining how to navigate the volume of disparate work being offered on the evolution of morality and (2) figuring out what is meant by morality, our very thing to be explained. 39 2.2.1 Navigating the Disparate Landscape of Evolutionary Explanations of Morality First, (1). When confronting this abundance of multidisciplinary empirical and theoretical work on the evolution of morality, surprisingly little philosophical attention has been given to the task of organizing and exploring what, if any, relationships exist in this mesh of research. As Wilson (1999) speculated in Consilience, “[w]e are drowning in information, while starving for wisdom. The world will henceforth be run by synthesizers, people able to put together the right information at the right time” (p. 294). Setting aside the merits and faults of Wilson’s grandiose vision to unify all of knowledge and bridge the gap between the humanities and the sciences, I take the current discourse on the evolution of morality, spread across multiple disciplines as it is, to be in need of just such a synthesis.32 Are these various research programs into the evolutionary origins of morality ultimately providing us with competing alternative explanations? If the evolutionary psychologists have gotten the explanation of morality correct, does this mean that the abstract computational models of the evolutionary game theorists are wrong (or vice versa)? Alternatively, if the evolutionary game theorists have constructed models for genetically determined behaviors that explain and predict moral behaviors, does this render the work of evolutionarily minded anthropologists moot or at best redundant, if the explanations of the latter could be reductively subsumed by the former? Do animals even have morality? If not, do we really need to pay any attention to the work of ethologists? Why should we, if the phenomenon we want to understand, morality, is distinctly human? Or could it be that these research programs are parts of a larger whole that can be unified into a coherent explanation, despite their differences? I hold this latter position, and my primary contribution as a philosopher will be to 32 I certainly don’t expect to be running the world in any capacity, however, and will leave that to the other sorts of synthesizers Wilson envisions. 40 present the case for an evolutionary explanation of morality that is a multi-level explanation that necessarily includes the explanatory work being done in ethology, evolutionary psychology, and evolutionary computational game theory. This is the “Entangled Bank” metaphor that I have employed to help conceptualize my project. If we imagine that we are currently bogged down in the muddy river bed of historical investigations into the evolution of morality, with all the mucky baggage that they have brought along, we now stand before a vibrantly lush and complexly interwoven wall of new growth vegetation. In the dense foliage before us, each type of plant symbolizes a research discipline that is exploring the evolution of morality. While they are evidence of fresh growth, they spring from that same foundation of historical evolutionary explanations of morality that have potentially mired us in debates surrounding naturalistic fallacies, hard genetic determinism, unwarranted anthropomorphism, and other murky worries. These different types of plants have erupted upward and are interwoven and knotted together, making it less immediately clear where one ends and the other begins. The range of their root system is poorly defined and their branching in need of pruning. However, if we can scale the Entangled Bank, it may be possible to ascend above the muck and arrive at a robust and compelling evolutionary explanation of morality that holds promise for informing our understanding of biology, natural history, human nature, moral systems, metaethics, and perhaps even normative ethics. The task at hand, then, is to venture cautiously into the brambles, survey the landscape, and assess the best path upward. For those who see the entire project of evolutionarily explaining morality as wrong-headed or pointless, the best thing to do would be to give up on trying to climb the entangled bank and instead see where else the river might lead. For others, who believe that the multiple research programs are 41 exclusive, either because they see them as are competing, incompatible ways of organizing and explaining the world or as ultimately reducing into one another, the path forward is to remove the invasive plants that do not belong on the bank until a cleared path has opened. Another way forward, and the solution that I present and defend, is to look at the types of plants before us as parts of a greater whole, each covering a different level of the bank, which can be interwoven and braided together, strengthened enough for us to grab hold of them and pull ourselves upward as we ascend the otherwise slippery bank. In Chapter 3, I survey the landscape before us, presenting a reasonably detailed account of the major disciplinary research projects being conducted on the evolution of morality, identifying their defining assumptions, methodologies, and explananda. This will enable me in Chapter 4 to present the case for an inclusive interdisciplinary explanation of morality that satisfies the standards of casual explanations we should expect of science, while also insulating the overall project—explaining the evolution of morality—from some its strongest objections. 2.2.2 What is Morality? The remainder of the current chapter is focused on the second philosophical issue, (2) which I take to be of utmost priority: figuring out what is meant by the term morality. If morality is the explanandum33 for which we have been promised an evolutionary explanation (e.g. de Waal, 2006; Alexander, 2007, etc.), we minimally ought to be able to expect a relatively clear explication of that explanandum, the concept of morality. 33 Again, I use explanandum in a merely general sense to mean “that phenomenon/phenomena being explained,” rather than in the technical way in which Hempel employs the term in his D-N Model of scientific explanation. 42 There are two strategies we might employ to answer the question “what is morality-as- explanandum?34” The first strategy is to attempt a descriptive project, an effort to try and construct a reportive definition for morality-as-explanandum. In such an endeavor, by looking at how the term “morality” is used by evolutionary researchers35 and theorists, we would essentially report how the term “morality” is actually used in practice by evolutionary researchers and theorists. Of course, there may be more than one definition of morality employed by evolutionary researchers, so a thorough reportive definition needs to identify as many usages as possible. The advantage of seeking a reportive definition is that, if we are interested in what evolutionary researchers are explaining (or, at least, are attempting to explain) when they talk about morality, we ought to look at what those researchers believe they are aiming at with their explanations. Such a conception of morality-as-explanandum would be descriptively accurate with the actual research programs being done. Furthermore, if it turns out that evolutionary researchers across the disciplines that I have identified share a conception of morality-as- explanandum, then this might tell us quite a bit about the possible relationships (or lack thereof) between the research programs. Finally, having a reportive definition of morality-as- explanandum equips us to evaluate the evolutionary explanations of morality by comparing it to whatever philosophical conception of morality one holds. If someone holds a conception of morality that is radically different from the phenomena being described and explained by evolutionists, they will not be terribly convinced that evolutionary explanations have or could provide an account of morality. 34 Which is really just a way of asking “what is the concept of morality?” that is identified and explained as a phenomenon? 35 Here and throughout I use “evolutionary researchers” as a shorthand way of referring to the psychologists, neuroscientists, cognitive scientists, ethologists, and game theorists who investigate the evolution of morality, sometimes through empirical research and sometimes through theoretical work. 43 The alternative strategy would be to provide a stipulative definition for morality that may, or may not, align with the way the term is understood and used by evolutionary biologists, game theorists, and psychologists. A stipulated definition would not be about describing how the term “morality” as used by evolutionary researchers but would rather be asserting with some normative force that this is how we should think about morality. Such a stipulative definition might even be drawn from the conceptual work of philosophers working on moral theory, in which case it would be akin to another kind of reportive definition. Instead of reporting on how evolutionary researchers use the term, though, it would be pointing to how moral philosophers have made sense of the term. In this dissertation, I will be employing the former strategy and providing a reportive definition of morality. I do this not only for the reasons above noted, but also because the primary focus of my project is evolutionary explanation itself. I do not presently wish to engage the long (albeit important) tradition of moral philosophy in attempting to assess what precisely constitutes a moral consideration, though I am not sure there is any prevailing philosophical consensus on the matter. Regardless, by providing a reportive definition of how morality is conceptualized in evolutionary explanations, readers will be in a position to compare this notion of morality to the metric of their own preferred philosophical conception. Nevertheless, I will also include the views of some prominent contemporary moral philosophers about what they take morality to entail, so the reportive definition will not be entirely isolated from philosophy. 2.2.2.1 Morality-as-Explanandum: The Search for a Reportive Definition Perhaps unsurprisingly, it can be hard to pin down exactly what evolutionary researchers have in mind when they talk about “morality” or “moral” elements, such as moral behaviors, 44 moral judgments, moral perceptions, moral emotions, and other similar phenomena. In part, this is possibly a result of the fact that many evolutionary researchers do not possess the philosophical training that makes them sensitive to (or perhaps interested in) conceptual issues. The complexity of morality likely does not help the matter. As I briefly discussed at the introduction to this chapter, morality is both complex and complicated. It extends between individuals and involves some, but not all, kinds of social interactions.36 These interactions, like all others, involve perception, judgment, motivation, and action, and morality is likely to involve particular kinds of perceptions, judgments, and actions. 2.2.2.1.1 Morality vis-a-vis Evolutionary History It is hard to know where to start when providing a reportive definition for how evolutionary thinkers have approached morality. When in doubt, however, there is probably no better place to start than at the beginning, which for our purposes will be with Darwin himself.37 As we have seen in Chapter 1, Darwin views something like the Golden Rule as the “foundation- stone” of morality (1871/2006, p. 871; p. 837). We get there, according to Darwin, by using our impressively developed intellectual powers (such as memory and reasoning) to build upon our biologically ingrained social instincts, which in combination with language and other cultural aspects of our society, can be strengthened and honed through habit into a progressing morality (818). 36 Of course, some philosophers hold that we have moral duties towards ourselves (e.g. M.G. Singer, 1958), and in this sense even an isolated person without social interactions with others could still have moral considerations. For simplicity and convention, though, I’ll focus on the social aspects of morality. 37 Even though some of Spencer’s work preceded Darwin’s own on the topic. 45 We do not need to revisit the other evolutionary ethicists here, as one thing we are not after when looking for a definition of morality is an evolutionary ethic. The attempt to construct a naturalistic ethical system that sought to provide the justification for a normative theory by appealing to our natural biology (e.g. Clifford, Stephen) or to the natural process of evolution itself (Spencer) were failed enterprises (see Farber, 1994). When investigating and explaining morality, we do not need something as bold as an evolutionary ethic. Rather, we are interested in “merely” describing and explaining the capacities and ways in which some social creatures navigate the kinds of interactions we would call moral. While I am not claiming that any attempt to construct a normative ethical theory from evolutionary insights is impossible, there would certainly be a heavy onus on the proponent to defend such an approach. We have the much simpler task of concerning ourselves with descriptions of how the world is, rather than attempting to draw inferences to prescribe how it ought be. Returning to our search for a reportive definition of morality that can serve as a morality- as-explanandum, we can easily find explicit engagement with the topic of morality in Kropotkin’s writing. He takes a strikingly similar approach to Darwin. He defines the “real principle of morality” as “freely giving more than one expects to receive,” and holds that in order to get there one must expand one’s considerations beyond mere love—which is localized and biased—into a perspective that embraces the “oneness with each human being” (1903/1978, pp. 39-40). It is less clear if Kropotkin, like Darwin, holds that something about our mental powers is what enables us to repurpose the love rooted in our biology, but this seems like a reasonable interpretation. Dawkins takes quite a different approach. By focusing on the “selfish” gene as the unit of selection, Dawkins believes that little about our biology will get us to a moral society, because 46 he believes our biological nature is selfish at its core (1976/1989, p. 3). Morality, if it is to come in at all for Dawkins, must be a concerted cultural effort involving conscious reflection and education. Dawkins specifically talks about “disinterested altruism” presumably as the pinnacle of morality (though he cynically notes it has “never existed before in the whole world” (pp. 200- 201)) and notes the theoretical possibility that humans reach it by resisting our genetic nature with our impressive cultural capabilities. In this way, Dawkins falls into the camp that de Waal (2006) labels as Veneer Theorists (de Waal also places Huxley in this tradition). On the view of the Veneer theorist, human nature is immoral, or at least amoral, and morality is like a thin cultural veneer applied over and in opposition to that core. Nevertheless, for Dawkins it seems like morality is something akin to “disinterested” altruism, even if it is unattainable in practice on his cynical view. 2.2.2.1.2 Morality vis-a-vis Ethology (Animal Behavior) Turning now to de Waal himself, we can shift our focus to the “Modern Era” of evolutionary explanations. Frans de Waal is the most prolific and well-known ethologist (primatologist specifically) of the modern era, and he has devoted significant attention to the questions of animal nature, human nature, and the evolution of morality (see his collected 2006 text). Following MacIntyre, de Waal believes that morality is a “group-oriented phenomenon” comprised exclusively by the “two H’s” of Helping and not Hurting (p. 162). Any social norms not related to helps and hurts are, at best, mere etiquette-like social conventions. In this way, de Waal follows in the very long tradition that has looked at altruistic behavior, which initially presented as the “problem of cooperation” (see Chapter 1) and has since gotten an incredible amount of attention, including as potentially moral behavior. As a reminder, 47 altruistic behavior is the kind of behavior that helps the recipient(s) but imposes some kind of cost (or hurt) onto the performer, such as when an organism shares food. Morality, though, is about more than just others-benefiting actions. Social insects such as ants and honeybees exhibit a wide range of complex cooperative social behaviors that help their hive mates, yet one would be hard-pressed to maintain that they possess morality or that they were in some way moral beings. We take morality to involve something additional, something particular about how the individual perceives and judges the situation at hand. This is the distinction between biological altruism and psychological altruism (see, for instance, Sober & Wilson, 1999). de Waal himself recognizes this and arranges morality into three levels (in ascending order): moral sentiments (e.g. emotions and psychological components), social pressures (e.g. punishments, rewards, and reputation), and judgment/reasoning (p. 168). In the same text, de Waal describes Robert Wright (a scientific journalist who has written extensively about evolutionary psychology) as subscribing to the same Veneer Theory of morality that de Waal himself so thoroughly rejects, noting that we are “potentially moral animals—which is more any other animal can say—but we aren't naturally moral animals” (p. 344). This attitude leads de Waal to dismiss Wright as a Veneer Theorist (2006, p. 11), who de Waal believes construes morality to be some cultural feature that is independent of (and in some sense opposed to) our underlying biological nature. If this labeling is correct, then it would suggest that Wright should not think any appeal to our underlying biology or psychology could help explain morality. In a commentary to de Waal, however, Wright elaborates with a bit more clarity on his own position, giving us an expanded sense of what he takes morality to mean. Rejecting the dichotomy between a naturalistic (in the genes) and a Veneer (in culture) theory of morality, Wright argues for what he coins a naturalistic veneer theory, which “sees humans as 48 often covering self-serving motives with a moralistic veneer, but sees the veneer-building process itself as genetically, not just culturally, grounded” (in de Waal 2006, p. 96). Wright, then, seeks evolutionary explanations of the genetic and cultural evolutionary processes that collectively produce moral guides to behavior. 2.2.2.1.3 Morality vis-a-vis Evolutionary Psychology It is worth comparing Wright's position to Jonathan Haidt's (2007) review of moral psychology, especially since Haidt is himself a prominent evolutionary moral psychologist. According to Haidt, moral psychology has developed an account of human moral judgment that identifies two types of cognition involved in these decisions: fast emotion-based affective intuition and slower less-affective moral reasoning (p. 998). These essentially provide moral motives that are “implemented in a variety of affect-laden intuitions that arise quickly and automatically and then influence controlled processes such as moral reasoning” (p. 1001). Evolutionary psychology seeks to give explanations for these genetically-based mental mechanisms, be they of the intuitive or cognitive kind, by appealing to natural selection and its role in creating these mechanisms in ancestral selective environments. On this view, the explananda of moral evolutionary psychology are the mechanisms in the mind that are involved in making moral judgments and producing moral motivations. How these explananda relate to morality-as-explanandum will be explored in Chapter 3. Turning now to modern evolutionary moral psychology, we can also find instances of psychologists providing an account of what morality means. Both Pizzaro (2001) and Haidt (2008) note that moral psychology was rooted for a time in the paradigm of Lawrence Kohlberg’s (1969) account of human nature. On Kohlberg’s cognitive-development view, moral development occurs as children learn and grow, a development that ultimately culminates in 49 “postconventional responses, in which one goes beyond one’s society and justifies rules with references to abstract and universal principles of justice” (Haidt, 2008, p. 67). Morality, then, was the practice of such justification-providing reasoning. Both Haidt and Pizzaro, though, present modern, evolutionary-informed alternatives to the Kohlbergian conception of morality. Haidt defines morality by pointing to a coevolution and culture and genes wherein “[m]oral systems are interlocking sets of values, practices, institutions, and evolved psychological mechanisms that work together to suppress or regulate selfishness and make social life possible” (p. 70). Somewhat similarly, Pizzaro replaces the Kohlberg model of moral reasoning with a view of moral judgment that accommodates both cognitive reason and emotional motivation. Each source can influence the other, and emotions allow “us to utilize their influence to serve our higher-order moral beliefs, as an “energy source” of moral judgment and action (p. 371). Evolutionary moral psychology assumes and investigates a morality that is emotional and cognitive, which roughly tracks along the biological and cultural components.38 2.2.2.1.4 Morality vis-a-vis Computational Evolutionary Game Theory I now turn to the next major stream of research, that of computational evolutionary game theory, pioneered by J. McKenzie Alexander (2007), who extended the general agent-based approach to computational game theory (Skyrms, 2004), exploring specifically the explanandum of morality. Indeed, Alexander’s book where he advances his view is boldly titled The Structural Evolution of Morality. For Alexander, “morality comprises a set of heuristics that govern behavior in interdependent decision contexts that work to the benefit of each person in society when followed” (p. 23). The task for evolutionary game theory, if it is to give an 38 Acknowledging, of course, the deep interplay between “nature” and “nurture” at the heat of these and other perspectives within evolutionary biology. 50 explanation of morality, is to provide a plausible account of how evolution can produce such heuristics (moral norms). Much like the work of Skyrms, the social structure matters and is a powerful influence upon how this cultural evolution can operate. Alexander does note that the biggest objection to his view is that the account he lays out may simply be presenting moral behavior in the “thin sense” of morality, and not actual moral action in some think sense that includes the “rich concepts, emotions, and principles which underlies moral reasoning and, more importantly, motivates moral agents to act the way they do” (269). Alexander goes on to note that evolutionary game theory, even if it can lead to a thick sense of morality, still needs to be connected with a psychological aspect, namely our moral psychology (270). Developing this line of thought even further, he proposes a distinction between natural and artificial virtues, each being a type of solution (behavior) to problems. The difference being that natural virtues are those that are “embodied in emotions and other cognitive machinery” (284), precisely the sorts of machinery studied by evolutionary psychology. It should be mentioned, though, that Alexander himself is neutral as to whether this machinery is composed of the evolved psychological mechanisms described by evolutionary psychology (footnote 11), though it is certainly an opportunity. On the other hand, artificial virtues are solutions produced by cultural evolution that emerged from aspects of our society. 2.2.2.2 Reportive Morality, Reported Despite the complexity of the concept of morality as used by these evolutionary researchers, I hold that there exists a somewhat universal sense in which they have conceptualized the term. For all of the above thinkers, morality involves an interaction between some sort of reasoning that combines cognition with emotion, even though in Dawkins’ case, the interaction is one of resistance, which is quite unlike the converse view that the emotional base 51 needs to be augmented as in the view of Darwin, Kropotkin, and de Waal. In this way, these thinkers mirror ethicist Peter Singer (1981) who also believes that morality is about expanding the circle of our moral sentiments to larger and larger groups, until we have included even animals (as Darwin too thinks will be included). Evolutionary psychologists Haidt and Pizzaro do not specify the ways in which the interaction between cognitive and emotional mental mechanisms ought to play out to arrive at a thick sense of morality, but they certainly emphasize the need for both. Another theme that emerges is the idea of impartiality, what Dawkins calls “disinterestedness” and what others consider to be the ability to think in other’s-interest focused ways, as if from the view of an “impartial spectator” (Kitcher 2006, borrowing from Adam Smith). Finally, the role of “self-command” (Darwin), restraint (de Waal), or being able to overcome particular impulses (Dawkins) runs through several of these conceptions of morality. This aligns with ethicist Christine Korsgaard’s (2006) identification of autonomy as central to morality, as it permits the agent a meaningful opportunity to assess on options and reflect on which one ought to be pursued. What, then, shall we adopt as our morality-as-explanandum, if we wish to be as descriptively accurate as possible to the evolutionary research programs that have and will continue to investigate it? Morality-as-(evolutionary)-explanandum is concerned with the complex way in which certain kinds of social interactions are resolved. In particular, morality is about a moral sense, the feeling of a motivational ought, that tends to be evoked by social interactions involving helping and hurting. When encountered, the moral subject’s resolution of these sense-of-ought-situations involves an interplay between genetically-based psychological hardware, reasoning ability, and cultural influences. In this way, morality-as-explanandum can 52 include biological and cultural components, emotional and rational cognitive processes, and the deep natural history of these elements. 2.2.2.2.1 Reportive Morality versus Morality vis-a-vis Philosophy We might wonder what, if any, relationship exists between this concept of morality-as- explanandum articulated above and the philosophical concept of morality. Morality has, after all, been the domain of philosophers for a long time. Critics may even critique the order of my very project, worrying that I have put the cart before the horse. Instead of beginning with the ways in which contemporary evolutionary researchers are conceptualizing morality, perhaps we should have started by endorsing (or developing) a philosophically defensible notion of morality and then looking to see how, if at all, evolutionary research might intersect with it. Otherwise, we run the risk of having an explanation of some biologically-based features (capacities, intuitions, predispositions, behavioral tendencies, etc.) that amount to nothing but a “so-called” morality, while potentially failing to reveal anything insightful about “true” morality. Nevertheless, I believe there are three reasons to support the reportive approach to understanding morality-as-explanandum, upon which the rest of this section will focus: (1) we are interested in explanations, (2) there is no philosophical consensus of the moral domain, and (3) our biological nature may set the capacities for our moral nature. The remainder of this section will explore these points. 2.2.2.2.1.1 The Focus is Explanations, Not Value Theory The first reason to look at the reportive account of morality in lieu of a philosophical account of morality is that this project is interested in the actual evolutionary explanations of 53 morality that have been and continue to be offered. Even if the evolutionary researchers working on this problem turn out to be studying a phenomenon that does not overlap with the philosophical notion of morality, they are still offering evolutionary explanations about a kind of motivational tendency that arises from the interplay between evolved mental architecture and cultural elements during interactions that involve, for instance, the welfare of others. Some moral theorists might reject this as having anything to do with morality. A staunch Divine Command theorist, for instance, believes that morality is ultimately dependent upon a divine being (e.g. God), and acting in ways that are moral requires acting in accordance with the wishes (commands) of that divine being. In this way, it might be argued that the evolutionary story about our moral origins is not telling us anything about morality-as-Divine-Command, unless it can in some way be shown that the process of evolution was producing aspects of our morality that in some way aligned with the morality of the divine being (whether intentionally or accidentally). Nonetheless, even in this case, the evolutionary explanations are still informing our understanding about a set of behavioral capacities and tendencies, and even if this is entirely disconnected from one’s preferred philosophical understanding of morality and the moral domain, it is still offering a scientific explanation of something about ourselves, and is no less interesting than understanding our other biological capacities (such as for language, mathematics, and so forth). Even granting this objection, the attempt to understand and integrate the evolutionary explanations of “so-called” morality would be a worthwhile endeavor, but I think that there is a stronger potential connection between the reportive sense of morality-as- explanandum and morality-as-philosophical-concept, which will be explored in section (3) below. 54 2.2.2.2.1.2 No Philosophical Consensus about the Moral Domain If we were to start with a philosophical conception of morality, instead of a reportive account drawn from the evolutionary research fields, we have one of two options open before us. First, we might look for a reportive notion of morality as offered by philosophers who specialize in value theory (ethics, metaethics, etc.) that is some sort of consensus view. Such a universal account of morality, however, does not exist within philosophy and is part of the reason why ethics has been such a deeply and continuously explored philosophical field for thousands of years. While we could simply adopt one of the philosophical positions about morality and its account of the moral domain in order to look and see what, if anything, evolutionary approaches offer in the way of explanatory insights about such a concept, this strategy would only appeal to moral philosophers who already ascribed to that same particular notion of morality. For instance, adopting a consequentialist position about morality would limit the moral domain to situations where two or more possible actions will result in differing utility calculations (however we make sense of “utility,” be it happiness, pleasure, et cetera). On such an account, the motivations and intentions of moral agents is irrelevant to morality, except in so far as these psychological features might be relevant to calculations of the utility produced by any given course of action. While adopting a consequentialist stance about the moral domain and then looking to evolutionary explanations of features of that domain might directly motivate our project for a moral theorist who ascribes to that same flavor of consequentialism, it would not be terribly interesting for any ethicists that would demarcate the moral domain quite differently, as a deontologist or virtue theorist would do. Given this, I think the more strategic approach is to look at morality vis-à-vis evolutionary researchers. Once we have an evolutionary understanding of this notion of morality, moral philosophers can investigate to what, if any, extent the reportive morality-as- 55 explanandum overlaps with their preferred notion of morality-as-philosophical-concept. If the concepts do not overlap significantly, the moral philosopher may be warranted in thinking that the evolutionary approaches have explained something about a particular set of social behaviors (just like we might get explanations of foraging, mating, language acquisition, and so forth) but that they have not explained morality. If, on the other hand, the concepts do align to some degree, evolutionary insights can be said to be offering at least a partial explanation of that sense of morality. Some differences between morality vis-à-vis evolution and morality vis-à-vis philosophy might even suggest areas for fruitful philosophical exploration and expansion. For instance, while some ethicists maintain that we have moral duties to our (future) self (e.g. M.G. Singer, 1958) or to the flora and fauna of the environment (e.g. Svoboda, 2012), the reportive notion of morality-as-explanandum does not seem to capture such issues given its focus on social interactions between two (or more) agents. This is not to say that the evolutionary explanandum of morality could not be expanded to include such domains of consideration. For instance, just as Darwin has argued that the interplay between our mental powers, culture, and sympathetic sense allows us to feel that sympathetic sense of ought not just for family but also for community member, stranger, and non-human animal, a similar case could be made for feeling imperious “oughts” about our interactions with the environment or our future self. At times we seem to feel guilty or ashamed about letting ourselves down, and this is likely the same sort of moral sense we experience when we fail others. While much work would need to be done to explore and defend such an account, which is not within the purview of this paper, it is at least possible that the domain of the reportive morality-as-explanandum might be expandable to incorporate even more elements should an ethicist feel that some important elements of morality were missing. 56 2.2.2.2.1.3 Biology Might Inform Philosophical Morality Another reason to start by looking at evolutionary accounts of morality before considering philosophical accounts is that we might think that our biological capacities should in some way inform or constrain the notion of morality. That is, perhaps the kind of creatures we are reveals something about the nature of morality. It is worth remembering the danger of evolutionary ethics (recall Farber, 1994). The claim that we are moral creatures is ambiguous. It might mean that we are morally good creatures, that we (at least tend to) act in the right way, but this is not the sense in which I or the modern evolutionary researchers considered within this project tend to think about humans as moral creatures. Being moral creatures merely means that we have the capacity to perceive, judge, and respond to moral situations. Ants, despite their astounding organizational cooperation, are not moral creatures in this sense. They act in cooperative ways, but without the requisite mental architecture to perceive and process their situation in a way that would qualify them as moral agents. We humans, however, with our increased cognitive capabilities, are moral creatures, in so far as we have been endowed by natural selection with a moral sense. There is a sense in which the kinds of creature we are could inform how we think about morality and the demands it places upon us. Game theorists employ the assumption of bounded rationality when modeling how humans approach economic issues, rather than a model of people as perfectly rational and objective agents (Alexander, 2007, pp. 5-7). Due to our very nature, game theorists argue, we are not capable of considering and evaluating opportunities as perfectly rational agents would, because the limited capacities of our actual minds are inadequate to facilitate such ideal deliberation. In a very similar way, one might make an argument for a 57 bounded morality, which is to say that the way humans can be expected to go about resolving moral challenges is likely to be constrained by their underlying (biological) moral capacities. In philosophical discussions about practical reasoning and ethics, a case is sometimes made for the principle that “ought implies can” (e.g. Sinnott-Armstrong, 1984; Sapontzis, 1991). Proponents of the “ought implies can” (OIC) principle hold that for someone to have a moral obligation to do something, they must in fact be capable of doing the thing. We cannot expect people to be beholden to unreasonable and unrealistic moral demands, such as preventing a harm they were otherwise powerless to prevent given the situation. If evolutionary explanations can reveal to us features of our moral nature—the capacities of our biologically-based moral architecture—then I would argue that any philosophical account of morality should be compatible with this moral nature. Otherwise, if the moral theory places the moral subject under undue or unrealistic expectations, then it seems ill-equipped to serve as a guide to conduct. This also relates to issues of moral alienation (Railton, 1984) that can arise when a moral theory is too burdensome and time consuming when moral subjects attempt to adhere to it. While this is not to say that any philosophical account of morality must be built upon the reportive morality-as-explanandum notion of morality, those accounts which diverge significantly from the biological basis of our moral capacities will have some work to do to defend itself against the objections that is alienating or violating the ought implies can principle. This fascinating and important issue is one that is orthogonal to my project at hand, but suffice to say that I believe having a robust understanding of our moral nature (what sort of creature we are) can help to situate how we think about our philosophical moral theories (what sort of creatures we should be). In this way, starting with a reportive account of our evolved moral capacities is not putting the cart before the horse, but is instead helping to assess the horse in 58 order to inform us about the limits of the cart (size, maximum weight, etc.) that we choose to harness to the horse. 2.2.2.3 Do (non-human) Animals have Morality? One area that scholars thinking about the nature of morality sometimes focus upon is the question of whether or not morality can be ascribed to any non-human animals. On the one hand, I do not think that this is a terribly important question for our purposes here. For one thing, it strikes me as impossible to answer with any confidence and, moreover, even if we could, its answer does not have much practical import for how we ultimately need to investigate and construct an evolutionary explanation for morality. Even if humans are the only creatures to which we are inclined to ascribe morality, given the continuity of biology and our shared ancestral past with gradual modification, for a robust explanation of morality it will still be valuable and necessary to investigate the biological building blocks of morality that we find in the “lower”39 animals (I will argue for this in more detail in Chapter 4). Might animals with cognitively rich lives, like elephants, dolphins, or primates have something closely resembling the human subjective moral experience? Possibly. I certainly would not be surprised if we learned that they did, though nothing changes on my account when we conservatively assume they do not. Part of the challenge in assessing whether or not animals possess morality is the problem of other minds, which is especially tricky when investigating animal minds. Since the subjective 39 Here, of course, I use “lower” as shorthand for animals that are less mentally and culturally complex than humans, and not as any way to evoke the classical notions of a hierarchy of life that was prevalent in the Scala naturae. In a technical sense, no creature is “more evolved” than any other, as all life forms trace their evolutionary history back along roughly the same 4.5 billion years of evolution from the same common descent. 59 experiences of non-human animals may be so different from our own, we cannot as easily employ the same sort of inferential or analogical solutions we might use when forming beliefs about the mental states of other humans. Thomas Nagel’s (1974) well-known piece, “What is it Like to be a Bat?” famously chooses bats as an example of (presumably) conscious beings whose subjective experiences are so different from our own, thanks in large part to their sensory use of echolocation, that we are supposed to be wary of any ability on our part to be able to objectively understand that experience. While Nagel’s piece is intended as a specific criticism against materially reductivist views of the mind by establishing inaccessibly subjective qualia, I would like to borrow and adapt his famous thought experiment. We might instead task ourselves with the following challenge: “what is it like to cooperate like a bat?” While classic examples of cooperative behaviors in animals tend to focus on primates (e.g. de Waal 2006), much work has also been done on vampire bats. These bats live in social groups and can be observed sharing food with other bats. Observational and experimental research has confirmed that the blood regurgitation is based not just on kin-based decisions but also reciprocal altruism (recall Trivers 1971), since bats form relationships to non- related “buddies” with whom they would preferentially share food (Wilkinson 1984, 1988, 1990). From a survival standpoint, this is an important insurance policy for a creature like a vampire bat, which can starve to death after two days of not eating. There are certainly strong selective pressures favoring reciprocated cooperation in these circumstances, just as there are strong pressures for establishing the means by which bats can identify other individuals and assess whether or not to share food when prompted. Cooperative grooming plays a large role in 60 bats’ daily40 lives, and it seems that bats perform grooming behaviors as a way to initiate and maintain reciprocal food-sharing relationships (Wilkinson 1990). Given all of this, would it be fair to say that bats have morality? Put differently, are bats moral creatures? They certainly seem to have a rudimentary society, that includes cooperative behaviors, “character” signaling, a means of assessing the “reputation” of other bats, at least in so far as such an assessment, whatever it is ultimately based upon, serves as a crude metric for making food-sharing “decisions.” But the scare quotes throughout my previous claim underscore the difficulty with such attributions. When the bat performs (or withholds) the regurgitation of blood, is it making an intentional decision or just performing a largely deterministic instinctive behavior41 in response to a set of stimuli that includes, among other things, evolved heuristics that contribute to resolving received requests for food sharing? Do bats feel emotions like sympathy toward their roost-mates? Do they experience a sensation of that “imperious” ought when presented with such cooperation opportunities? I believe that definitively answering these sorts of questions—especially the question about a sense of ought— is impossible, given the problem of other minds, generally, especially when the other mind is as different from ours as a vampire bat. The risk of anthropomorphizing the situation and unduly ascribing our subjective experiences onto the consciousness of the bat is high, but fortunately there is not too much at stake when we withhold such attribution. On my view, nothing is lost by taking the conservative assumption that only humans (and not even all humans)42 possess morality it its full sense. 40 Pun intended, as bats spend large portion of the daytime in their roosts grooming. 41 Here I do not mean to imply that all instincts, in so far as we call the biologically innate motivational forces instincts, are deterministic in their expression. 42 There are interesting questions as to whether certain kinds of mental disorders like sociopathy and psychopathy inhibit the extent to which one could be thought of as a moral agent. I believe 61 Nevertheless, when researchers and philosophers do attempt to answer the question of whether or not non-human animals have morality it tends to be a very productive intellectual exercise in that it forces the thinker to be more mindful of their explication of the concept of morality as they explore its potential to serve as a demarcation criterion to see how far, if at all, it extends across the web of past and present lifeforms. In that sense, it is helpful to consider what those who have tackled the question of (nonhuman) animal morality have said. For what it is worth, the evolutionists we have considered all limit their conception of morality to humans. For Darwin, it is man “alone who can be ranked as a moral being,” since we have no reason to assume that animals have the ability to consult their past and future actions and motives with approval or disapproval (1871/2006, p. 827). Dawkins thinks that “we [humans] alone on Earth” have the possibility to overcome our genes in the pursuit of disinterestedness (1976/1989, p. 201). Only humans fully possess the third level of morality (judgment/reason) on de Waal’s view (2006, p. 168). Evolutionary psychologists like Haidt and Pizzaro are explicitly limited in scope to studying humans and human judgments, but presumably would be hesitant to ascribe such complex to animals. 2.3 What Lies Ahead Now that we have a better sense of where we are hoping to get, the task is to figure out which path up the entangled bank is best. In the next chapter, I review the explanatory practices that evolutionary researchers have employed in their efforts to offer evolutionary explanations of morality, including evolutionary game theoretic approaches, animal ethology, and evolutionary psychology. Given the especially contentious history of evolutionary psychology in particular, I that being human is likely necessary but certainly not sufficient for having morality in the robust sense. 62 will also defend it from the claims that it just recommits the same sins of human sociobiology, which include both methodological and ethical objections. Evolutionary psychology, while not completely exonerated of potential worries, is at least insulated from the most severe methodological and ethical objections that faced human sociobiology, and as such can be retained as a potentially valuable part of the Entangled Bank, ready to be integrated with the explanatory approaches of evolutionary game theory and animal ethology. The case for this explanatory unification is made in Chapter 4. 63 CHAPTER 3: Surveying the Landscape: Explanations of Morality 3.1 Introduction Now that we have a sense of what we are after—the evolutionary view of morality-as- explanandum, as explicated in the preceding chapter—we need to figure out how an evolutionary explanation could get us there. The place to start, I believe, is by looking at the dominant disciplinary trends which have offered evolutionary explanations of morality: studies of the computational game theory, animal ethology, and the human mind. Specifically, we need to examine the claims of these disciplines to reveal the ways in which they purport to offer explanations. Just as we explicated the concept of an evolutionary morality-as-explanandum in the past chapter, here we will philosophically clarify the way these disciplinary approaches generate explananda. This will put us into a position to braid the approaches into a pluralistic, unified explanatory framework in Chapter 4. As an added task, because of the highly controversial nature of evolutionary psychology (both historically and contemporarily), I will invest some effort into defending it from criticism, since if it is supposed to be woven into the braid of vines, I must show it is not already rotted through to the core. I demonstrate that evolutionary psychology is not felled by the biggest objections against (human) sociobiology, and as such need not be prematurely jettisoned. 3.2 Games: Victorious Strategies as Explananda As noted earlier, a modern branch of inquiry within the evolutionary exploration of morality involves the use of evolutionary game theory, especially highly computational models. Game theory, generally, looks to model an interaction between two or more participants, and as such can investigate the strategies those participants may employ. “Strategy” is used very 64 loosely, to refer to any behavioral response that one of the modeled participants might employ. In the case of evolutionary biology, mathematical models solved the problem of cooperation43 by showing that, even if selection happened only at the level of the individual organism, altruistic behaviors could be positively selected for and preserved by natural selection under certain conditions, such as if the recipient of the altruism was sufficiently genetically related to the performer (Hamilton, 1964) or if the altruism was sufficiently reciprocated by the beneficiary in the future (Trivers, 1971). As computers became available, biologists quickly employed them in modeling cooperative behaviors, treating behavioral responses as strategies that “players” in the game could follow. In evolutionary game theoretic approaches, the players in such games model organisms, who like the players in the game will have opportunities to interact with one another. These strategic interactions are behaviors, and the strategies that dictate each behavior are genetically based and therefor inheritable with modification, like any Darwinian trait. If a strategy is to be a potentially adaptive solution (a behavior producible by natural selection), the evolutionary game theoretic approach assumes that the strategy must increase the relative fitness of the players using the strategy, ultimately moving the strategy to stable fixation as a Nash equilibrium. Such an equilibrium means that the strategy is resistant to exploitation by “cheater” strategies that seek to take advantage of it because no players would gain an advantage by altering their strategy. In evolutionary game theory, this is called an evolutionarily stable strategy (ESS). In a basic Prisoner’s Dilemma scenario, wherein two players must each choose to either cooperate or not cooperate (“defect”) without knowing what the other player will choose. If both 43 See Chapter 1 65 players cooperate, they each enjoy the largest benefit. On the other hand, if a player cooperates when the other defects, the defector receives a modest benefit while the cooperator either receives no benefit or may even incur a cost. The TIT-FOR-TAT strategy, which instructs the player to cooperate on their first interaction with another player, then to do whatever the other player did on the previous encounter, gives the advantage of cooperation to cooperators, but insulates them from the costs of cooperating with free-riders (Axelrod and Hamilton, 1981), thus making TIT-FOR-TAT cooperation an ESS. This game-modeled demonstration is taken to constitute a plausible evolutionary explanation for such a strategy, since it demonstrates the possibility for such a behavioral strategy to have been produced via natural selection given its overall benefit to individual fitness for the organisms that employ (possess the trait for) the strategy. Thus, for computational evolutionary game theory, behaviors themselves are taken as the explanandum, and to explain a behavior is to demonstrate via a game theoretic model its ability to reach an equilibrium as an ESS. More recently, evolutionary game theorists like Bryan Skyrms (2004) and Jason Mackenzie Alexander (2007) have used this approach to expand from considerations of only biological (genetically-based) behaviors to also allow for the investigation of the potential cultural evolution of strategies, most importantly adding aspects of social organization and structure to the simpler game theoretic models upon which their work expands. It is worth noting, though, that even on this more modern approach these strategies need not be cultural norms, nor need they be consciously chosen. For example, Skyrms (2004) discusses activities of cooperative bacteria that resemble a solution to the Stag Hunt dilemma (pp. 45-47), and this sort of strategy resides solely in the genetics of the bacteria, though their communication and association between one another is relevant to understanding the whole biological story. In this 66 sense, the modern approaches of Skyrms and Alexander can be agnostic to the source of the strategy, because whether it resides as an instinctive mandate in the genes or is acquired as a social norm44 of one’s society, the game theoretic model can evaluate its stability. The focus remains the explanation of why particular strategies in social interactions evolve within the parameters of a given computer model. Ultimately, the project Skyrms develops is one that looks at how something like a social contract—cooperation in Stag Hunting, for instance—might be explained through cultural evolution. The explanandum for Skyrms' type of account is a cooperative strategy, and he argues that explaining it will require appealing to connective features between the cooperative strategy itself as well and the social structure it is situated within, which includes also the kinds of associations between players. Let us look again at the TIT-FOR-TAT strategy from Axelrod and Hamilton (1981) that is taken to be an evolutionary explanation for how cooperative behavior can have evolved as a product of natural selection. The more recent approaches additionally model, at least to some degree, the social structures between players in the game. As Alexander (2007) notes, TIT-FOR- TAT is not the optimal solution to prisoner’s dilemmas and any prisoner’s dilemma that runs for an indefinite amount of time will fail to have an optimal strategic solution, since dominant strategies can always be exploited (p. 60). When dynamic social networks are added to the evolutionary game model, players of the game interact with other players in non-random ways that can take into account proximity and preferential interaction targets, even when initial 44 One might interpret the strategies, or norms, in these simulations as something akin to Dawkins’ (1976/1989) memes, since the basis of the strategy need not be an inheritable bit of genetics, but could be acquired through cultural means such as learning or imitation as well. By meme, Dawkins meant bits of information that can spread from brain to brain, a sort of cultural replicator and unit of selection analogous to the biological gene. He did not, of course, simply mean humorously captioned photos of cats, though such things certainly qualify as examples of memes. 67 interactions may be randomly determined. When the game theoretic model includes the social structure of a population of players, this structure influences what behavioral strategies can emerge most commonly in Nash equilibriums. After the first few generations, a pattern appears. Cooperators begin to prefer to visit cooperators and to avoid visiting defectors. Given the payoff matrix and the dynamics of network formation, this preferential association is to be expected: when cooperators visit defectors, that interaction is not reinforced because the sucker’s payoff S equals zero. When a cooperator visits a cooperator, he receives the reward R for cooperating, which increases the probability that he will visit that cooperator in the future. In the limit, cooperators will solely associate with cooperators and avoid defectors. (p. 94) In this way, cooperators behaviorally aggregate and form clusters, and “cooperation will always dominate in the limit as the probability of an agent updating his strategy shrinks to zero” (p. 99). Even when the chance of strategy update is greater than zero, if it is sufficiently small and the population reasonably large, the vast majority of trials still see populations move to a final state of all cooperators (p. 100). So what it is for an evolutionary game theoretic approach to offer an explanation if some behavioral strategy is for it to provide a model that demonstrates that the strategy of interest is likely to reach a fixated equilibrium in a population. Such explanations do not require that every iteration of the model result in the strategy going to fixation, since the nature of probabilistic interactions entails that sometimes unlikely interactions might disproportionately occur and prevent the strategy from achieving fixation. An evolutionary game theoretic explanation, then, is to demonstrate that under a set of modeled parameters it is both possible and likely for a strategy to achieve fixation, such as over 950 out of 1000 simulations of the game result in fixation. In such an instance, we have an explanation that accounts the emergence of a strategy as a solution to a particular strategic problem by virtue of demonstrating the way in which benefits of that particular strategy improve the differential success and reproduction of the player 68 (organism) that possesses the strategy, much like general evolutionary arguments explain adaptations by highlighting how the an adaptive trait increased the likelihood of reproductive success (fitness) for those individuals that possessed the trait, thus likely increasing the prevalence of that trait across future generations. When the strategies modeled by evolutionary game theorists are morally-relevant behaviors such as cooperation, trust, fair distribution, etc., they are contributing an evolutionary explanation of that moral behavior. I do not deem it necessary to present a rigorous methodological defense of computational evolutionary game theoretic approaches, as I shall for evolutionary psychology, because it does not seem to face the same level of skepticism (or, in some cases, ire) that evolutionary psychology faces. This is almost certainly because the explicit allowance for cultural evolution within the model avoids the sort of ethical objections (biological determinism) that have made evolutionary psychology so threatening. Evolutionary game theory, like the work of Skyrms and Alexander, also has a smaller footprint in the academic and public discourse than does evolutionary psychology (or animal ethology). Nevertheless, it will be an important part to an integrated account of the evolutionary explanation of morality. 3.3 Animal Ethology: The Rest of the Animal Kingdom Ethology is the study of animal behavior. Technically speaking, humans are of course animals, but ethology typically focuses on the research of behaviors in non-human animals. It is worth appreciating that “behavior is not restricted to movements, and an animal that appears to be quite inactive may “behave” in this use of the word. For example, a male antelope standing motionless on a termite hill indicates his ownership of a specific area” (Immelmann, 1980, p. 2). 69 Ethology can be, largely, a descriptive enterprise that seeks to observe and catalog the behavior of animals. Animal behavior can be observed in the animal’s natural habitat, in artificial settings like zoos or preserves, or can even be observed under experimental laboratory conditions. In addition to the scientific practice of observing, identifying, and describing behaviors, ethologists can also seek interpret and explain. Ethological explanations attempt to explain why a behavior exists. Such explanations can look to explain the proximate causes of the behaviors, such as an account of the neurological systems that process particular stimuli and output responsive behaviors, or they may seek to provide an evolutionary explanation that presents a case for the adaptiveness of a particular behavior, treating behaviors (or the capacity for certain behaviors) as biological traits that are heritable, variable, and subject to natural selection like other more classically physical traits. In both cases, the explananda of ethology are the behaviors of animals. An important aspect of ethology is that it often adopts a “bottom-up” view of behavior, even complex social behaviors, which appreciates a deep “continuity between past and present, child and adult, human and animal, even between humans and most primitive mammals” (de Waal, 2006, p. 24). Behaviors can be understood and explained, at least in part, by appreciating how the biological building blocks that underlie it and exist in an evolutionary gradient across the phylogenetic tree that links species evolutionarily via their most recent common ancestors. By presenting us with a picture of the biologically based behaviors within animals, we are granted a glimpse into our evolutionary ancestry, when we think about the morphology of behavior comparatively. While we are not descended directly from any extant species of today, the common ancestry—which links us to the animals of today via our most recent common ancestors—can still suggest to us something about our evolutionary history. In this way, 70 comparative considerations of animal behavior can help inform us of the past that might be deeply buried within our genes. For ethologists like de Waal (2006) and Bekoff (2006), the inner nature of animals is generally more emotionally rich and complex than has been classically presumed. In order to explain the behaviors of deeply social animals, we need to account for the evolutionary purposes behind their behaviors. To the extent that animal social behaviors start to resemble morality (presumably not at all in ants and quite a bit in apes), these evolutionary ethologies are of increasing interest to my project at hand, and de Waal in particular sees his work in primatology (the study of primate ethology) as particularly relevant to understanding the evolution of morality in light of the bottom-up building blocks for morality that are found in a gradient across the phylogenetic tree of our closest primate kin. It may be helpful to consider an example of an evolutionary ethological example put forward by de Waal. He notes that behaviors aimed at the alleviation or prevention of distress in others can be found in a variety of animal species, but that it is “unclear if spontaneous responses to distressed conspecifics are explained by (a) aversion to distress signals of others, (b) personal distress generated through emotional contagion, or (c) true helping motivations (2006, p. 29, emphasis added). To explain why such behavioral responses occur requires an ethological explanation. In constructing such an explanation, the evolutionary perspective is valuable in two ways. First, it allows for the explanation of building blocks like the feeling of empathy by appealing to the adaptive function of empathy. de Waal notes that empathy first evolved in mammals to strengthen parental care behaviors, serving as an affective motivator to respond to the needs of offspring (p. 24). The adaptive benefit of such an empathetic “moral sense” (to harken back to 71 Darwin, see Chapters 1 and 2) is straightforward, in that individuals possessing such a trait would be more likely to have improved fitness because their offspring would survive better given the greater attentiveness to their needs. Second, evolutionary insights are valuable to the explanatory endeavor as it allows for phylogenetic inferences to be drawn about the evolutionary history of the behavior. de Waal notes that there is evidence of emotional contagion operating across apes and monkeys (pp. 40- 41), but by looking comparatively at studies of monkeys and apes it is apparent that targeted helping appears in a gradient. While reconciliation behaviors, those that facilitate the mending of social bonds between two individuals that were involved in a confrontation, are observed in “species after species,” consolation behaviors that involve a third-party individual consoling another after a conflict are found only in the great apes (pp. 35-36). To explain this behavior, only found in the great apes, de Waal notes that such cognitive helping behaviors require a high degree of cognitive ability and self-awareness that can facilitate behavioral responses that can go beyond what mere emotional contagion accounts predict and that situate the individual organism to adopt to some degree the perspective of others, as well as what is causing that perspective. In this way, within the great apes and humans, cognitive empathy emerges as the interplay between the emotional affective building blocks, like empathy, and the improved cognitive elements that allow for understanding and resolving the emotional states of others. 3.4 The (Human) Mind: Mental Architecture as Explananda One primary explanandum of morality is the human mind and the processes by which it resolves moral situations. As the site of moral perception, moral decision-making, and internal 72 moral motivations, the human brain plays a central role in human morality. It is the connection between our inner and outer worlds, and through the architecture of its hardware and the content of its software we are able to recognize, reflect upon, and respond to moral stimuli. Evolutionary psychologists view the brain as an adapted organ, and attempt to understand the hardware of the human brain as an adapted product of natural selection. 3.4.1 Evolutionary Psychology When it comes to studying the evolution of the brain and its evolved moral capacities, the dominant approach is evolutionary psychology, which is a broad research program that includes the efforts of academic researchers hailing from a variety of disciplines, with academic homes in psychology, neuroscience, cognitive science, or similar departments and programs. The distinctive feature of evolutionary psychology’s research program is that it assumes the human mind is “a vast and heterogeneous array of complex computational machinery” that outputs behavior (Cosmides & Tooby, 1997). This machinery is composed, at least in part, of functionally specialized modules which are domain-specific mechanisms for processing situations and outputting appropriate45 behaviors. These mechanistic modules were formed by natural selection as adaptive solutions to ancestral challenges that our ancestors faced. For instance, evolutionary psychologists see the highly prepared learning of phobias (Seligman, 1971) as evidence of just such mental modules. If the mental mechanisms that exist for the rapid learning of phobic responses, which can be hard to eliminate once acquired, are indeed the products of natural selection, then this helps explain why we so commonly encounter people with phobias of things like snakes, spiders, and heights. Avoiding these sorts of encounters may 45 Appropriate in the sense that it is related to the situation at hand, not in the sense that it is “morally appropriate.” 73 have had an evolutionary advantage in the ancestral environment where such things could readily pose mortal risks. Conversely, we do not typically observe people with a phobia of cars, even though we are all far more likely in the modern world to be killed by a car than a snake. Cars were not a problem for our ancestors when these phobia-producing prepared learning mechanisms were acquired through random variation and selected for due to their adaptive value. In this way, according to Cosmides and Tooby, understanding the adaptive problems faced by our evolutionary ancestors can help us understand and explain the neurophysiological structure of our modern minds. The human mind, on this view, is massively modular. With regards to evolutionary moral psychology, recent trends within evolutionary psychology are largely sympathetic (pun certainly intended) to Darwin's own speculations on the moral sense's foundation in sympathy. In Jonathan Haidt’s review of evolutionary moral psychology, for example, he notes that “the building blocks of human morality are emotional” (Haidt, 2007, p. 998). Haidt and Joseph (2006) offer an account of moral judgment that roots the foundations of morality upon five innate moral intuitions that have evolved in the context of our ancestral environment to handle challenges involving harm, reciprocity, in-group association, hierarchy of the social group, and purity. These intuitions, according to Haidt and Joseph, are biologically designed components that function as “first drafts” for moral behavior, akin either to mental modules in the sense developed by Sperber (2005) or to prepared learning mechanism like phobias (Seligman, 1971). These intuitions, then, are biological bits of mental architecture that contribute affective emotional content to particular kinds of experiences of the world, but like any first draft does not tell the whole story. The contribution of these intuitions is conjoined with cognitive reasoning and cultural interaction that can build upon the foundation of these evolutionarily granted intuitions to allow for judgments about a much broader set of experiences 74 than what the original function of the intuition served. In this way, Haidt and Joseph’s account is very much in line with the views of Darwin, de Waal, and others (see Chapter 2) that view morality as the interaction of biological components granted by natural selection, cognitive reasoning, and cultural elements. According to Haidt (2007), moral psychology has developed an account of human moral judgment that identifies two types of cognition involved in moral decisions: fast emotion-based affective intuition and slower less-affective moral reasoning (p. 998), which builds upon his social intuitionist model (2001). These intuitive types of cognition essentially provide moral motives that are “implemented in a variety of affect-laden intuitions that arise quickly and automatically and then influence controlled processes such as moral reasoning” (p. 1001). Evolutionary psychology seeks to give explanations for the genetically-based mental mechanisms, whether we think of them as modules (Cosmides & Tooby, 1997; Sperber, 2005), prepared learning, (Seligman, 1971), or intuitions (Haidt & Joseph, 2006), by appealing to natural selection and its role in creating these mechanisms in ancestral selective environments. On this view, the explananda of moral evolutionary psychology are the mechanisms in the mind that are involved in responding moral situations. Putting this simply, evolutionary psychology seeks to explain how brains are built by considering what are the metal mechanisms and why have they evolved. Evolutionary psychology continues the tradition of sociobiology in assuming that “the mind is not infinitely malleable” (Wilson 1975/1978, p. 267). Features of the mind’s biological structure—our evolved human nature—influence how we can and do interact with the world around us. In this way, evolutionary psychology resoundingly rejects the Standard Social Science Model, or what Pinker calls the “Blank Slate” view of human nature (see Pinker, 2002). 75 This view assumes that the mind is, for all intents and purposes, an infinitely malleable structure that is formed predominately through cultural transmissions such as learning. This perspective does not necessarily require positing an entirely miraculous evolutionary rift between humans and their nearest hominid ancestors, but it does take the position that any biological features of our minds are rendered largely insignificant by our novel cultural abilities, not unlike the type of view we saw earlier in Huxley. In an early critique of sociobiology, Morison (1975/1978) notes that Wilson himself admitted that his comparative ethnological approach failed to predict humans' unique traits (language, technology, culture-generation), the exact traits we are most interested in studying (p. 250). According to the Standard Social Science Model, a biological understanding of the mind can, at best, offer little useful insights into human behavior. At worst, applying a biological perspective to our understanding of human minds risks committing the fallacy of genetic determinism, which raises serious methodological and ethical objections against the entire enterprise, and these worries are at the core of the sociobiology debate noted in Chapter 1. Since evolutionary psychology serves as an integral part of my unified view of the evolutionary explanation of morality, I will respond to these objections and defend the enterprise from the critiques that, according to critics, felled sociobiology. This will also help to assuage the trepidations of any skeptical readers who are inclined to think that modern evolutionary psychology is just reinventing a useless wheel. 3.4.2 Defending Evolutionary Psychology: The Vestigial Threats of Sociobiology As noted previously, evolutionary biologist Jerry Coyne is one such critic writing “[t]he latest deadweight dragging us (evolutionary biology) closer to phrenology is evolutionary 76 psychology, or the science formerly known as sociobiology. If evolutionary biology is a soft science, then evolutionary psychology is its flabby underbelly” (quoted in Gray et al. 2003, p. 247-8). As further anecdotal evidence for this position, several years ago I attended a talk in the anthropology department here at Michigan State University that was being given by a well- known evolutionary psychologist46 whose graduate seminar I had recently taken. About halfway into the talk, an older professor from the anthropology department stood and walked out of the room. She paused in the doorway for a few moments before turning to face the speaker. She interrupted his talk to very publicly and passionately inform him that she was offended by his talk, that felt that evolutionary psychologists were “all the same” (lazy in methodology and rigor), and that they had little business talking about these sorts of issues. Without waiting for a reply, she turned and departed down the hallway. Remembering the hostility that Wilson encountered while giving talks, perhaps evolutionary psychology and sociobiology have more in common than just the view that the human mind as a collection of evolved components. Is evolutionary psychology just the zombie-husk of sociobiology, in need of being put down one final time? At the very least, evolutionary psychology is enjoying the academic success that sociobiology never achieved. The term “sociobiology” has largely faded out of common usage. There are few sociobiology interdepartmental programs or journals, and those that do exist focus almost exclusively on animals as opposed to humans. However, the relatively young field of evolutionary psychology does seem to be enjoying at least some of the academic success that (human) sociobiology never quite attained, even though Wilson's work is its evolutionary ancestor. Now, tenured professors identify themselves as evolutionary 46 Identities kept anonymous. 77 psychologists and top end journals publish their findings. This success, however, has clearly not convinced all of its opponents. Others seem to view evolutionary psychology as a triumphant phoenix that has risen from the ashes after the sociobiology research program was unjustly burned at the stake. Into this “vindication view” I would place thinkers like Pinker (2002, e.g. p. 135) and Wright (1994, e.g. pp. 345-348). Between these two extreme positions, there also exists a view somewhat not unlike a Hegelian synthesis that sees evolutionary psychology as a matured progeny that avoids at least some of the pitfalls of sociobiology (Sterelny & Fitness, 2003). I will argue that this is the correct way to think about the relationship between sociobiology and evolutionary psychology, expanding the brief defense provided by Sterelny and Fitness. In what follows, I argue that evolutionary psychology successfully avoids some of the major objections leveled against sociobiology and seems to mitigate others. Although there are several important difficulties still facing evolutionary psychology, I do not feel that these problems warrant the fierce, condescendingly dismissive, and unwarranted rejection leveled against evolutionary psychology by its staunchest critics. On the other hand, I think that proponents of the “vindicated phoenix” view are too optimistic and uncritical of evolutionary psychology and, ironically, that they also risk failing to appreciate some of the most impressive improvements that the field has achieved by distancing itself from some of its sociobiological roots.47 For my purposes, I am content to demonstrate that evolutionary psychology can legitimately be incorporated into an evolutionary explanation of morality without also bringing along fatal objections to such a project. 47 A charitable interpretation might understand their largely uncritical optimism as a counter- response to the zeal of some of their opponents. 78 The critiques leveled against sociobiology fell into two categories: ethical objections and methodological objections (Caplan, 1976/1978). In Section 1 I consider the ethical objection against sociobiology and argue that evolutionary psychology, because of its focus on culturally invariable mental mechanisms, avoids these problems with the exception of possible sexist implications. Section 2 looks at the methodological difficulties of sociobiology and considers how evolutionary psychology has largely improved on these failings though still faces some difficulty, namely with the challenge of providing adaptive explanations. These challenges will be addressed by the unified evolutionary explanation of morality that I present in Chapter 4. 3.4.2.1 Ethical Objections: Genetic Determinism It was the ethical objections that led to such a voluminous debate over sociobiology and gathered protestors to Wilson's talks. These objections accused Wilson of promoting genetic determinism (Allen et al.,.1975/1978; Sociobiology Study Group, 1976/1978). These critics believed the sociobiology program endorsed the idea that certain behavioral and cultural features within humans could be viewed as simply natural. If this was the case, then it could become a tool for justifying any current state affairs, especially if used by the politically conservative right. If inequalities or injustices existed within society between groups, then if one could argue those differences stemmed from underlying biological traits it could be used to excuse society from any social responsibility it might otherwise have to ameliorate the situation. The scientific quest to rank people based on their innate biological intelligence had been repeatedly criticized as little more than racism and social prejudice disguised as objective science (see Gould, 1981/1996 for a comprehensive discussion), and sociobiology was seen as an irresponsibly naïve reinvention of this deterministic project. 79 Wilson (1975/1978; 1976/1978) and others (Caplan, 1976/1978) believed that the ethical objectors were basing their argument on an unfair interpretation. In order to make some sense of this dispute, it will be important to understand just what sociobiology was claiming. The object of study for sociobiology was behaviors, and these behaviors were believed to be underwritten by genes. Behaviors were to be thought of 'organs' that were extensions of the genes. Several critics objected to the idea that there would be a single gene for any given behavior (Sade, 1975/1978; Allen et al. 1975/1978), but Wilson quickly responded that multiple genes could be involved in the production of a behavior. Wilson (1975/1978), to further defend himself against the determinist charge, also stated “[t]o an extent not known, we trust—we insist—that human nature can adapt to more encompassing forms of altruism and social justice. Genetic biases can be trespassed, passions averted or redirected, and ethics altered...” (p. 267). While this seems to imply quite a bit of flexibility in Wilson's picture of how genes contribute to behavior, his endorsement of the “multiplier effect” seems too hard to reconcile with this point. Re-emphasizing a quote from Sociobiology, Wilson (1976/1978) writes that even “a small portion of this [genetic] variance invested in populations might predispose societies toward cultural differences” (p. 296, emphasis in original). Wilson's idea here is that small genetic variations, presumably just a few genes, could produce large scale cultural differences between different human populations. In part, this allows Wilson to explain how genetic change could have kept up with the incredibly rapid cultural development over the past few thousand years of human history, given that evolutionary biological change proceeds at a much slower rate. Given this commitment, it seems to me that Wilson wants to defend a fairly powerful causal role for the genes in producing, in a rather unidirectional manner, much of culture. Thus, I am inclined to agree with the critics that Wilson's account here is strongly 80 hereditarian and deterministic. I do not think that Wilson himself had any conservative political agenda, but the approach certainly invited racist or other problematic values based on group differences to be codified as biologically grounded differences (when there was, in fact, no such biological basis—this will be explored more deeply in the next section on methodological objections). Given the passion of some of the current attacks against evolutionary psychology, one might wonder if they are motivated, at least in part, by the same sort of fear of determinism and its political implications. As an example of the resistance faced by evolutionary psychologists, Daly & Wilson (2007) describe how their work on the “Cinderella Effect”48 has been repeatedly misrepresented, dismissed for being obviously true, and dismissed for being patently false, all with very little professional civility being shown by the critics as they fill an 'anti-evolutionary- psych market niche' (a phrase the authors borrow from Wright) (pp. 394-397). Assuming that at least some of this sort of criticism is motivated by the presumption that evolutionary psychology dangerously flirts with determinism, I will argue that evolutionary psychology is not nearly as vulnerable to the criticism as sociobiology. Evolutionary psychology attempts to identify and explain the machinery of the mind, not behaviors. The focus of study is on mental mechanisms themselves, parts of the brain's physical structure. It is assumed that some of these mechanisms, just like other physical traits, are adaptations that were selected for under ancestral conditions. Cosmides and Tooby (1997) identify this assumption as the second principle of evolutionary psychology, and further developments in the field have refined this assumption. In this sense, then, despite the genetic 48 The term refers to the fact that being in a household with a stepparent is an increased risk factor for child abuse, even after controlling for socioeconomic status. This is presumably because some of the evolved mechanisms related to caring for one’s genetic offspring may not be present in stepchild-stepparent relationships. 81 basis of the mechanisms, they are less innate than the behaviors of sociobiology. Mental mechanisms require inputs from the environment to process, and as such there is no hard-wired environmentally invariable behaviors. Sociobiology on the other hand, which views behaviors as 'organs' expressed as extensions of a set of genes, seems to at least suggest such context inflexible behavior could be expected. Still, one might wonder if, given a particular input, will a mental mechanism invariably produce the same deterministic output behavior? The answer is no: one general principle of mental mechanisms is that they do not operate in isolation but interact in complex and rich ways as they regulate behavior (Barrett, 2008, pp. 183-184). Recent work in empirical psychology seems to support this view, noting that the fast emotive affective mechanisms involved in moral judgment can be 'overruled' by slower cognitive pathways, a result that is observed when moral judgments that are counter to the emotionally salient response take significantly longer for respondents to make (e.g. Greene et al., 2001; Haidt, 2007). Thus, conscious reasoning can alter the judgment or action made. Building from this, another core assumption of modern evolutionary psychology states that human nature can only be understood as a product of both our genes and our environment (Salmon & Crawford, 2008, p. 13), which would include the cultural context in which our mechanistic minds are situated. With all of these refinements over sociobiology's rather coarse look at behavior, it seems there is little room for a charge of genetic determinism to be leveled against evolutionary psychology.49 Even if worries still remain that evolutionary psychology might carry with it some weak form of determinism, there is no possibility for it to facilitate racists or culturally imperialistic values “ascending” to scientific truth. Wilson (1976/1978) notes that we might expect to find 49 Of course, even if evolutionary psychology was strongly hereditarian and entailed an inescapable genetic determinism, that would not provide an independent reason to think it was false. 82 cultural differences existing as a result of relatively small genetic variation, thanks to the multiplier effect (p. 296). In this sense, behavioral differences between races or genetically distinct cultures could be identified as a genetically determined feature of the groups' different natures. With evolutionary psychology this charge of racism is not a threat, as noted by Sterelny and Fitness (2003, p. 3). This is because it is a foundational assumption that mental mechanisms exhibit no genetic variation, except for potential variations across the sexes (Salmon & Crawford 2008, p. 13) on the grounds that humanity's evolutionary history is far too short to have allowed for the requisite changes between populations (which are also separated only by porous reproductive barriers). In fact, when differences are observed between cultures this counts as direct evidence against a culturally invariable bit of cognitive machinery—the very focus of evolutionary psychology. So, while Sterelny and Fitness are correct in noting that evolutionary psychology cannot be racist, they neglect to point out that it may very well still face charges of sexism. Since evolutionary psychology assumes that there are very likely differences between the male and female cognitive machinery because of our different mating strategies and life histories, it is possible that purely cultural differences between men and women might get cashed out as differences in our natures. For instance, Salmon and Crawford (2008, p. 14-15) discuss a variety of work that has been done in evolutionary psychology on the mating strategies of men and women. They note that findings on intra-sexual competition have suggested that women tend to criticize other women on the basis of their looks and promiscuity while men criticize other men based on their resources and achievements. This is seen as a possible biological adaptation because males would, according to the adaptive mating strategy, prefer mates who were young and faithful because this would increase chances of finding a fertile partner who would be more 83 likely to rear his genetic offspring (since males cannot be sure they are the parental contributor of genetic material). On the other hand, females, who can be sure of the paternal source(s) of genetic material, ought to prefer mates who can provide resources for her and her offspring, since she has to disproportionately invest in their production and care. This strategy is taken to be adaptive across many mammalian species with dual parental investment of care. However, though I have not read all of the cited studies nor the developments in the literature since, this kind of account seems like it could just be tracking cultural values rather than the operation of biological mechanisms. Even if the study looked at a cross-cultural section of humanity, feminists and historians will quickly note that most cultures have a longstanding patriarchal history where women were largely relegated to the domestic sphere while the public sphere was the domain of men. Thus, it would be unsurprising if men came to be socially valued and measured based on their professional achievements in this social sphere while women came to be valued based on their role in the private domestic sphere. If so, it would also be unsurprising if common cultural strategies emerged that relied on derogating your sexual competition based on their potential shortcomings in their (culturally-assigned) social sphere. Thus, there is a chance that the explanation here merely tracks vestiges of longstanding cultural sexism rather than any genetically based mental mechanisms. This general methodological problem will be explored in the following section, but the ethical objection is clear. While evolutionary psychology largely avoids the determinism problem and sidesteps the racist/imperialist dangers of sociobiology, there is still a chance that it might have sexist implications. This is not by any means of a fatal flaw of the theory, but it does mean evolutionary psychologists need to be especially cautious when making conclusions about differences between the sexes. 84 3.4.2.2 Methodological Objections: Testability and Adaptationism In addition to worries over its ethical and political implications, critics pointed out several methodological problems with sociobiology, noting that it was not falsifiable and was committed to an overly ambitious adaptationism (Allen et al., 1975/1978; Sociobiology Study Group, 1976/1978). I will argue that evolutionary psychology is genuinely testable and generates novel and bold predictions for research. Evolutionary psychology also does much better than its parent at dealing with the challenge of adaptationism, but it does still pose a significant difficulty for explanations within the field, even more so than in other areas of evolutionary biology. The first methodological failing with sociobiology, it was argued, was its failure to meet Popper's demarcation criterion of being falsifiable. There simply were no severe genuine tests to which it could be subjected, and it was guilty of employing ad hoc hypotheses. The Sociobiology Study Group (1976/1978) wrote The trouble with the whole system is that nothing is explained because everything is explained. If individuals are selfish, that is explained by simple individual selection. If, on the contrary, they are altruistic, it is kin selection or reciprocal altruism. … Sociobiologists give us no example that might conceivably contradict their scheme of perfect adaptation. (p. 288) The connection here between the adaptationism objection (which will be explored more fully later) and unfalsifiability should be clear. It is perhaps telling that in his reply to the latter Wilson (1976/1978) does not respond to this particularly damning criticism, aside from a rather short comment noting that not all modern human behaviors are adaptive, and indeed they may even be maladaptive (pp. 296-7). Far from solving this problem, his response further complicates the matter as we shall see below. Ruse (1976/1978) actually does go to the plate to defend sociobiology from this criticism by noting that it is falsifiable, in principle, and that is what counts. As a potential falsifier, Ruse proposes the existence of widespread cross-cultural incestual behaviors because such mating 85 strategies would have biological consequences and could not have been the product of natural selection. Still, the criticism of Allen et al. (1975/1978) argues that the reason sociobiology is unfalsifiable is because “when Wilson is forced to deal with phenomena such as social unrest, his explanatory framework becomes amazingly elastic. Such behavior is capriciously dismissed with the explanation that it is maladaptive, and therefore has simply failed to evolve” (p. 261). This criticism still seems to stand, despite Ruse's efforts. Perhaps Ruse's potential falsifier, if observed, would actually cause most adherents to abandon sociobiology, but one response consistent with Wilson's picture could be that it is actually a universal maladaptation, either resulting from a widespread “gene-trumping” cultural force or a maladaptive loss of the behavior in our evolutionary history.50 These responses might be dismissible as merely ad hoc, especially since it is unclear what new novel predictions they would generate for testing, but sociobiology seems to have readily available space to retreat into it deep within the “murky realm of unfalsifiability.” Evolutionary psychology, unlike sociobiology, is concerned with generating specific predictions which can then be subjected to testing by empirical psychology, cognitive science, and neuroscience. As Cosmides and Tooby (1997) note, one approach to generating such testable predictions is to speculate on adaptive problems humans may have faced, reconstruct this problem as a cognitive problem, and then create hypotheses about the neurophysiological basis that may have been designed by natural selection to aid in solving the adaptive problem. Applications of this research-guiding principle have allowed evolutionary psychologists to 50 The explanation that incest-avoidance behaviors simply never had the opportunity to evolve would not be very convincing because of comparative ethology. Many other mammals avoid incest and presumably have evolved behaviors that have enable them to do so, so the parsimonious phylogenetic reconstruction would have to place incest avoidance behavior far back on the evolutionary tree. Still, genetic variation might have disrupted this behavior somewhere in the human lineage. 86 propose and then test for a variety of domain-specific modular mechanisms, with some promising results for the existence of mechanisms involved in facial recognition, inferring the intentions of others, kin recognition, regulation of kin interactions, and social exchange mechanisms for cheater detection (for a review of such research see Barrett, 2008, pp. 175-183). In the realm of mate selection, specific hypotheses have been developed and then investigated as well. For instance, studies have tried to assess if men prefer a 0.7 hip-to-waist ratio in females, a number which was generated based on biological and medical data that suggested such a ratio was the best indicator of overall reproductive health when compared to other ratios (see Gray et al., 2003 for a (critical) discussion on this research). Perhaps the flagship exemplar (to borrow some Kuhnian language) of evolutionary psychology is the work that has been done around the social exchange mechanism. The hypothesis was that humans should be better at detecting rules violations in social contexts than they are when it came to rules violations in generalized abstract examples. In the ancestral environment, the ability to detect cheaters who broke social norms could be fitness boosting. As such, the existence of modular specialized mechanisms for handling social exchange was proposed and then tested. Several results found that people were generally terrible at applying rules like modus tollens and modus ponens51 to abstract examples (if a card has a vowel on one side, then it must have an even number on the other) but quite adept at employing the rules in social examples (if a person is drinking alcohol, they must be at least X years old). Of course, there is disagreement over whether the results of such studies provide strong evidence for a social exchange mechanism (e.g. Gray et al., 2008, pp. 259-265), but the predictions of the hypothesis could have easily been countered had no divergence at all existed between reasoning 51 Certainly no surprise to those of us who have taught intro logic. 87 abilities in the abstract and social contexts. Evolutionary psychology generates hypotheses that can be subjected to genuine tests through empirical psychology and other forms of neuroscientific investigation, and this is certainly a strong improvement over its sociobiological ancestry. Nevertheless, there is a closely related difficulty that looms over both approaches. The other methodological critique of Wilson's sociobiology was that it was guilty of adopting an unjustified adaptationist52 perspective that merely assumed aspects of human behavior and culture were adaptive (Sociobiology Study Group, 1975/1978, pp. 286-288). Gould and Lewontin, leading members of the Sociobiology Study Group, would later famously explicate this position in their “spandrels” argument (1979), which pointed out the limitations and risks in evolutionary biology of claiming that traits are the adaptive products of selection. The famous “Just-So Story” terminology entered into the parlance, noting that many appeals to adaptations seemed like nothing more than plausible post hoc stories that might explain how the trait evolved under natural selection. For instance, the giraffe's long neck was classically touted and taught in biology class as an adaptation that was directionally selected for because it allowed giraffes access to higher food sources. This was certainly a plausible and convenient explanation. However, a current alternative explanation is that the long necks may be a result of sexual selection instead. The problem of identifying a trait as adaptive and constructing its historically accurate evolutionary explanation is a difficult one for all of evolutionary biology. However, the challenge of giving adaptive explanations for evolutionary psychology is particularly formidable, 52 This refers to an empirical adaptationism (as opposed to a methodological adaptationism). While there is a fascinating debate surrounding how we should understand the thesis of adaptationism and the implications thereof, that is a question for another project. 88 for a variety of reasons. In evolutionary biology, scientists have a few strategies available to try and identify a trait as an adaptation, with direct experimentation being the only means that can demonstrate causality. For instance, for the hypothesis that the unusually long tail feathers of widowbirds are adaptive and play a role in female mate selection, researchers took a group of male widowbirds and cut their tail feathers off before reattaching them. Some had feathers reattached so that their tails were quite short, others reattached to the original length, and some had their tails elongated. Then, the population was studied and the number of average nests per male was measured for each experimental group. It turns out that shortened-tail males had fewer average nests than the normal length birds while elongated males had the highest number of nests (see Conner & Hartl, 2004 for a discussion of this and similar experimental manipulations). Such experimental manipulations are difficult if not impossible to conduct with human subjects, especially because evolutionary psychology typically does not generate knowledge about the location of mental mechanisms but only tries to identify and explain them (not to mention, of course, the ethical implications of human subjects). However, evolutionary psychology does have one source of evidence to employ. Similar to knockout experiments in genetics, when studying mental mechanisms individuals with either genetic or developmental disorders or physical damage to the brain can provide illuminating information about the normal functionality of the cognitive machinery (Cosmides & Tooby, 1997; Barrett, 2008, p. 183). People with autism are quite adept at spatial reasoning yet deficient at emotional inferencing while individuals with Williams syndrome are unable to do basic spatial reasoning but are adept at emotional inferences, and this suggests that the universal, normally functioning architecture of the mind involves modular mechanisms for each type of reasoning (Cosmides & Tooby, 1997). Thus, just as with the exaggerated birds' tails, we can look to see if such differences are 89 correlated with fitness differences. Presumably, both disorders would reduce one's overall reproductive success (and one might even imagine inter-generational studies that tracked this for research participants). Of course, the conclusion that the longer tails were produced as adaptations in response to selective pressure relies on the assumption that the ancestral environment the trait evolved within was similar to the modern experimental environment. For most organisms, this is probably a fairly reasonable assumption unless we have climatic or ecological data to suggest otherwise. In the case of humans, though, the environment of evolutionary adaptedness (EEA) is quite divergent from our modern lifestyles due, primarily, to the massive cultural evolution that has occurred. In fact, Salmon and Crawford (2008) identify the discrepancy between our EEA and current environment as one of the foundational assumptions of evolutionary psychology. Thus, even if we could demonstrate the existence of a mental mechanism that was adaptive in our current environment, we would not have evidence that such a mechanism was produced as an adaptive solution by selective pressures in our EEA. Wilson's sociobiology was largely criticized for assuming an EEA that was inconsistent with current anthropological theories (Allen et al., 1975/1978, pp. 263-264). While any speculation on the EEA will be quite difficult, knowledge about the EEA, especially its physical aspects, has become increasingly better (Sterelny & Fitness, 2003, p. 3). The generally agreed upon EEA is the Pleistocene era, which spans from 1.8 million to 12,000 years ago (Salmon & Crawford, 2008, p. 15), covering a huge period of potential physical and cultural selective pressures. Alcock and Crawford (2008) argue that, while our knowledge of the EEA is not perfect, it allows for reasonable working hypotheses to be generated. They point out that things like poisonous animals could have posed real threats to fitness, so we should expect phobias to 90 be based predominately on things like spiders and snakes and not on things like cars, despite the fact that in the modern world we are all far more likely to be killed by a vehicle (pp. 42-43). Nevertheless, we might wonder why people develop things like koumpounophobia, a severe panic-inducing phobia caused by buttons (of the clothing variety). Even when a mechanism seems like it might have been adaptive given the evolutionary problems faced during the EEA, it is still often easy to suggest an alternative plausible explanation that underdetermines the evolutionary explanation. We can return to research that investigated male preference for female hip-to-waist ratio. Gray et al. (2003, p. 258) argue that interpreting the data to mean that men have a specialized mental mechanism for preferring a 0.5 hip-to-waist ratio could be an unjustified “Just-So” story because the same results could be explained by the presence of an evolved general mechanism that responds to “super-normal stimuli.” These are stimuli that exist beyond the normal ranges and cause a positive response. For instance, firefly males will prefer artificial firefly models that are larger than actual fireflies and plovers will opt to add eggs considerably larger than its own eggs to its nest (p. 258). Thus, Gray et al. argue we have little reason to accept the evolutionary explanation that claims the preference is a specific evolved mechanism for judging hip-to-waist ratio. The authors are correct that they have presented another alternative explanation, but this hardly seems like the end of the project. Their alternative explanation seems to me to be testable. Similar studies could be conducted that present men with a variety of line drawings of the female form that altered the size and ratio of other traits like hands and heads all the way into the 'super-normal' range. I suspect that such super-normal stimuli would not elicit male preference. Given this, even if there were an underlying general preference for super-normal stimuli at work, we should then expect some kind of evolved mechanism to have been produced 91 that applies this general preference to certain stimuli (such as hips) and not others (such as hands or the head). Alcock and Crawford (2008) advance a similar position that I think is absolutely right. They note that the Just-So Story criticisms against evolutionary psychology are largely unwarranted because evolutionary psychologists propose evolutionary explanations as tentative proposals that should always be subjected to further testing when possible (pp. 36-37). As an example, the authors discuss the wide variety of adaptive explanations that have been proposed for the excessive crying of babies but note that, rather than accepting one of these explanations as the truth merely because it is a plausible story, evolutionary psychologists went to task trying to come up with additional hypotheses and predictions that would vary between the different explanations and could be tested, ultimately allowing them to rule out adaptive explanations that did not withstand the investigations (p. 37). Nonetheless, even if we respect evolutionary psychologists for being tentative and cautious, we might wonder how often they will actually be able to present us with evolutionary explanations that are reasonably convincing. As we have noted, our limited knowledge of the EEA already presents some additional challenges specific to evolutionary psychology, given how much the human environment has been altered through culture. Furthermore, other features of evolutionary psychology present even more problems. Optimality models provide another way that biologists might approach the study of adaptations (Orzack & Sober, 2001), but this approach may prove especially challenging to employ in evolutionary psychology. For evolutionary psychology, cognitive mechanisms are the product of natural selection and the functionality of these mechanisms depends on the environment and potentially complex interactions with other mental mechanisms (as we saw in 92 the above section). Thus, it is unclear what we might model or assume as optimal. In the hips- to-waist ratios, it was noted that a preference for a 0.7 hip-to-waist ratio was assumed to be optimal, such that underlying mechanisms would predominately yield this response despite other factors. This is a strong assumption because it maintains that, despite the complex interactions between mechanism and the cultural differences, the mechanism for hip-to-waist ratio preference will manifest. We may actually share many universal and functionally specific mechanisms that will be hard to identify during experimentation because of the invariant way in which such mechanisms may or may not manifest as an output behavior. Furthermore, in the case of the hip- to-waist preference studies, there was reasonable biological and medical data that could be used to extrapolate what an optimal mate-selection strategy based on waist-to-hip ratio might select. It seems less clear, for instance, that optimal functions could be proposed and quantified for things like facial recognition ability or snake phobias, both of which have been proposed as specialized cognitive machinery produced by natural selection. But, failing to adhere to an optimality model would not mean that the underlying mechanism was not there, it could just mean that given our quite different modern environment the mechanism no longer functions in the way that it did when it evolved. While such an optimality approach may not be impossible to employ, it will face challenges. Another core assumption of evolutionary psychology is that the brain is a physical computer and processes information in a computational way (Cosmides & Tooby, 1997). This is, of course, an assumption that was not underlying sociobiology. Whether the brain does in fact function this way is an empirical question that may be challenged (e.g. Calabretta & Parisis, 2005) discuss some of the differences between the computational picture of the brain employed in evolutionary psychology versus the connectionist view that treats the brain like a neural 93 network), but I am content to grant the assumption of evolutionary psychology. Personally speaking, I know far too little about neuroscience or cognitive science to know if the computational model of cognition is in any empirical jeopardy. Nevertheless, it is a position that is also open to philosophical critique. The identity theory of mind, based on the physicalist assumption that the mind is identical to brain states, is of course incredibly controversial within philosophy of mind. A final key commitment of evolutionary psychology is worth noting. Both Cosmides and Tooby (1997) and Salmon and Crawford (2008) ascribe most of our mental mechanisms a largely unconscious role. This point does not seem terribly contentious, and most critics of evolutionary psychology would likely grant that much of the processing of our minds is unconscious (such as all of the knowledge-how involved in performing activities as simple as walking across the room). Recent empirical work in moral psychology seems to provide more evidence for thinking that mental processes involved in something as seemingly conscious as making judgments can also be largely unconscious. Wheatley and Haidt (2005), working from the assumption that affective disgust was evolved to help play a role in motivating moral judgments, found that hypnotically induced disgust caused participants to make moral judgments that neutral events were morally wrong. When asked to give conscious justification of these responses, the authors noted that most respondents struggled to find reasons and offered post hoc reasons such as the character in the story was simply “up to something” or untrustworthy. Evolutionary psychology has, on my view, little in common with Wilsonian sociobiology. Both research programs assume that the continuity of evolution allows for a biological investigation into human nature, but after this common foundational assumption I think the differences become far more pronounced than the similarities. Evolutionary 94 psychology, though still a broad field of research, avoids any charge of merely codifying cultural practices as genetically determined extensions of our biology because of the sensitivity to the complex genetic and cultural interplay involved in producing our actions. Nevertheless, there are pitfalls to watch out for and opportunities for improved rigor. For instance, evolutionary psychologists need to be especially critical of their own studies on male and female difference because there is the possibility that cultural values (and most dangerously sexist beliefs) could be misidentified as the products of underlying evolved cognitive mechanisms. Most importantly, evolutionary psychology has impressively distanced itself from sociobiology by becoming a clearly testable discipline. The biggest difficulty still facing evolutionary psychology, however, is the difficulty of giving adaptive explanations (which is, in fact, the very heart of the discipline). While this is a difficult problem for all of evolutionary biology, I have provided reasons why I think it will be an even harder challenge for evolutionary psychology. Nevertheless, as part of a unified evolutionary explanation of morality, as I present in Chapter 4, we can improve the robustness of our evolutionary explanations. I believe it clear that evolutionary psychology is, at the very least, a promising research program. It certainly does not warrant the presumptively dismissive and hostile attacks that are leveled against it and which quite possibly stem from an unfair conflation with sociobiology. Still, it is important to be mindful of its limitations, as many evolutionary psychologists themselves seem ready to acknowledge. 3.5 The Entangled Bank: Ready to Ascend Now that we have a sense of the types of evolutionary approaches that lay before us, most importantly the sorts of explananda they can explain, I am in a position to present my case for how we can proceed to a robust evolutionary explanation of morality. 95 CHAPTER 4: The Way Out: The Integrative Explanation We know that the major evolutionary disciplines considered in my project are aiming at shared explanandum (Chapter 2), but also that the disciplines are only equipped to explain pieces of the puzzle (Chapter 3). Is there a way to bring these explanatory efforts together in a meaningful or productive way, to braid the vines of the Entangled Bank together? I believe that there is, and the task of the current chapter is to make the case for such an explanatory “Moral Synthesis” (to pay homage, with no hubris intended, to the periods of the Evolutionary Synthesis and the New Synthesis in biology). We need to be clear about what an explanatory Moral Synthesis will have to avoid if it is to be successful. First, if we were to try completely “biologicize” ethics, putting the task of explaining cultural elements fully onto the shoulders of biologists, this would exclude anthropologists from contributing purely cultural models of morally-relevant phenomenon. Doing so would uproot some of the foliage from the Entangled Bank, including work in the evolutionary study of the human mind that investigates the evolution of our cognitive reasoning and the capacity it grants us for adopting a disinterested perspective, consulting cultural norms, and otherwise participating in and maintaining culture. It would also eliminate computational models of game theory that investigates the cultural evolution of norms. While the Entangled Bank would become less congested and easier to ascend, we would arrive at a summit that does not much resemble the morality-as-explanandum we are after. Conversely, if we follow Veneer Theorists like Huxley, Wright, and possibly the disgruntled cultural anthropologist from my earlier anecdote (who vehemently rejected the legitimacy of evolutionary psychology), any attempts to explain morality would need only 96 consult the cultural elements that contribute to the production of the moral “veneer,” and approaches explaining biological aspects would only be helpful in so far as they could tell us about the parts of our nature that the cultural veneer needs to suppress and restrain in the pursuit of morality. This, too, would prune the Entangled Bank but opens a path that does not lead where we want. The solution we need, if we are to reach for the robust evolutionary view of morality, morality-as-explanandum (Chapter 2), is one that incorporates the insights and explanatory contributions of all the pieces of the Entangled Bank. If we can braid these together, we have a chance to ascend to our desired destination. 4.1 The Presumed Moral Synthesis While it is rare to find much explicit collaboration between researchers in evolutionary psychology, evolutionary computational game theory, and ethology, we can find hints of the desirability or need for such a Moral Synthesis. There are a few places where evolutionary psychologists have talked in this way with regard to game theory; one such place is the Foundations of Evolutionary Psychology (Eds. Crawford & Krebs, 2008). Krebs (2008), one of the editors of the volume, seems to implicitly assume a strong connection between game theory and psychology, using language such as “dispositions to behave” when talking about the work of game theorists like Trivers, thus implicitly imbuing game theorists search for evolutionarily stable strategies with psychology’s focus on motivational states. Schmitt (2008) contributes a piece about the research tools available to evolutionary psychologists, and considers game theory simulations to be one category of research methodology available to evolutionary psychologists (pp. 218-219). Kenrick, Sundie, and Kurzban (2008) view game theory as a promising means by 97 which to explore the effects of the decision-rules discovered by evolutionary psychologists, speculating that “incorporating evolved decision rules and biases into a game theoretic framework [may] simultaneously make game theory more realistic and make evolutionary models more quantitatively precise” (p. 354). A similar optimism can be found in Alexander’s game theoretic work, wherein he speculates that the solution to the big problem facing evolutionary game theory approaches like his—that it does not capture a “thick sense” of morality—might be best be solved if “evolutionary game theory, together with experimental psychology and recent work in the theory of bounded rationality, can explain some of the structure and content of our moral theories by working in tandem” (p. 274). I take this as evidence that evolutionary researchers assume the existence of something like an explanatory Moral Synthesis, or at least evidence that they would like there to be such a thing. Given our conception of morality-as-explanandum, we have a theoretical need to braid the explanatory approaches together if we are to capture all of the elements involved in the phenomenon of morality and we find a seeming willingness for such an integration expressed by at least some of the researchers. Can such an integrative explanation be supported by a philosophically robust notion of explanation? 4.2 Complexity The evolutionary view of morality (Chapter 2) presents us with a dauntingly overwhelming concept. Morality, on this view, necessarily involves many elements: the mental modular architecture within the human brain; the processes by which those modules perceive (receive) inputs; the way in which one (or likely many more) of these mechanisms computes the inputs into outputs, a process which itself often involves an interplay between fast affective 98 mechanisms and slower more cognitive reasoning and which produces motivational dispositions in the agent; and finally some output behavioral response to the situation. But we are not done. The processing that converts a perceived moral situation into a judgment or behavior also might involve a host of cultural elements, those “secondary guides to conduct” in Darwin’s words. This potentially includes societal expectations for behavior, such as laws, etiquette, or moral rules. Anticipation of blame or praise for acting in particular ways can easily become part of the process as well. The moral situation itself involves not just one agent, but also the second (and third, and fourth, and…) involved in the interaction. And this is only to mention the present causal influences that contribute to resolving the moral interaction. To think evolutionarily, the explanation exponentially expands the scope of causally-relevant pieces into the past, into the deep history under which evolution and its various forces, most notably natural selection, has contributed to gradual changes across many generations of reproduction, to many if not most of the phenomena contained in our moral interaction. The causal web of morality is incredibly complex. When two agents have a moral interaction, all of the components of their mental pathways that handle moral judgments causally interact. External stimuli are perceived and processed by the innate affective intuitions (Haidt & Joseph, 2006). The output of this intuition then is evaluated by a cognitive reasoning mechanism (Haidt, 2001) and it may alter the intuition or not, but during this process the reasoning is causally influenced by external considerations, such as concerns about adhering or violating social norms, possible approval or disproval, anticipations about the other agent’s likely behavior, including analysis of that agent’s behavior. The behavior of the first agent then casually interacts with the behavior of the second agent, and the state of the world is altered. The outcome of this interaction then goes on in a feedback process to causally affect each agent’s 99 anticipations about future actions. How the agents react in one scenario has consequences that can become causal contributors to how the agents act at the next opportunity (e.g. in a TIT-FOR- TAT style of interaction, if the second agent behaves in a non-cooperative way, this becomes a relevant part of the first agent’s future interactions). This vignette only considers an interaction between two agents, each with her own set of genes, mental mechanisms, motivations, and (cultural) experiences. But many (perhaps most) moral situations involve multiple agents. Each additional agent added would require exponentially more vectors of causal influence added to the web of causal interactions. Taking the evolutionary perspective, the outcome of this moral interaction has a causal effect, either positive or negative, on each agent and this may or may not affect the relative fitness of each in the future. Looking temporally in the opposite direction, to the past, the evolutionary history of the innate aspects of each agent’s mental architecture has a long causal story that involves innumerable behavioral interactions between ancestors, each producing some causal influence upon the reproductive life histories over the course of generations and generations. The description above . With morality being such a complex system, we will need a concept of explanation that can accommodate such highly complex systems. 4.3 Explanations Explanations, in the most general sense, are a way to make sense of something. They are the answers we look for when faced with “why?” questions. We might want to know why the television series Firefly was cancelled after one season. This why-question is answered by a statement from the former Fox Entertainment president, who explains that the low number of viewers relative to the high cost of the show made it an unprofitable investment (Owen, 2011). If 100 someone tells us her favorite novel, we can ask why that book is her favorite. Then she can explain her subjective preference, probably by offering us a brief list of the reasons why this particular story resonated so significantly with her, and she might even go on to explain why we should add it to our own reading queue. A boss can ask an employee why he missed the morning meeting, to which the employee might explain “I’m so sorry, I hit a dog on my drive in this morning.” This can help the boss understand, in two senses. The boss understands the reason for the absence, and the boss might even be understanding of it, in effect forgiving the employee for his failure to meet an expectation (“wait, I can explain!”). A child might protest bedtime by asking why they must go to bed so early, and the caregiver may respond with one of many explanations, ranging from the simple imperative exertion of the parent-child power hierarchy (“because I said so!”) all the way through an exhaustive list of all the benefits provided by a full night of sleep (e.g. “your body needs to recharge lots of energy for the zoo tomorrow”). These types of explanations permeate our everyday experiences and help to orient our navigation of the world. Ultimately, those offering the explanations intend for the explanation to contribute to an improved understanding of the phenomenon of interest (the cancellation, the matter of taste, the failure to attend, the justification of a policy). They are not, however, scientific explanations, and the scientific task of explaining the natural world will be explored in detail in the following section. 4.3.1 Explanations in Science Scientists do many things—observe, describe, measure, predict, experimentally test—but perhaps nothing is more central to science than explaining the world, and the other scientific activities are often done in service to providing explanations. Scientists aim to provide answers 101 to why-questions, specifically why-questions about the natural causal structure of the phenomena found within the scope of a scientific field. Biochemists, for instance, seek to provide explanations for the changes that occur when organic molecules typically involved in the life processes of organisms interact, and they construct these explanations using a set of disciplinarily-shared concepts, facts, constants, and other such elements that collectively determine the scope of relevant phenomena for investigation and the methodological tools available to investigate these phenomena. One major goal for philosophers of science has been to provide a philosophical theory of scientific explanation. The history of this endeavor will be briefly traced in the following two sections. As we shall see, the prevailing attitude is that explanations in science are typically causal. 4.3.1.1 Explanations in Science: Arguments from Laws Consider the classic falling apple anecdote. Newton sat under a tree, pondering the universe, when a serendipitous apple fell. Newton wanted to know why apples fell to the ground (not just apples, of course, he was greatly interested in the motion of all bodies, especially the planets). His search for an answer to that question ultimately yielded his law of universal gravitation, which describes the way any two bodies exert an interactive force upon one another. Newton had finally explained the apple’s fall. This sort of explanation is what Hempel’s (1965) Deductive-Nomological (DN) Model of scientific explanation attempted to cover. The central aspects of scientific explanations under this model are right in the name. Explanations on this account are logical arguments (deductive) that involve laws or law-like regularities (nomological). More specifically, explanations are 102 valid and sound deductive arguments incorporating these elements in their premises. The thing to be explained, the explanandum, is deductively concluded from the premises, the explanans. In this way, the premises of the argument explain its conclusion. With something like Newton’s apple, this account seems to works well. Combining the initial facts about the size and position of the apple and conjoining those with Newton’s laws of motion, we can “prove” (i.e., conclude deductively) when and at what velocity the apple hits the ground. In cases where the laws were statistical rather than deterministic, Hempel offered an analogous Inductive-Statistical (IS) Model of explanation. The explanatory relationship was the same, in that the explanans (premises) explained the explanandum (conclusions), but in this case the explanans included a statistical regularity. This model was widely influential, and led many to view scientific explanation as fundamentally being about laws, with Carnap (1966/1995) claiming “no explanation—that is, nothing that deserves the honorific title of “explanation”—can be given without referring to at least one law” (p. 6). The DN model, as influential as it was, encountered problems. The symmetrical relationship between premises and conclusions missed something important about explanations, as shown in a classic counterexample. If a flagpole casts a shadow on a sunny day, an argument could be constructed to explain why the shadow has the length that it does at any given time, when the position of the sun and the height of the flagpole are put into the explanans. Those features explain the shadow’s length. If instead the length of the shadow is placed in the explanans and the height of the flagpole is placed as the explanandum, which is logically symmetrical, the shadow’s length is explaining the flagpole’s height. Explanation should not 103 travel in both directions. The flagpole’s fixed height and the variable position of the sun are what should, taken together, explain the shadow’s current state, not vice versa. Kitcher (1981) tried to retain an account of explanations as arguments by endorsing a unificationist view of scientific explanation. According to Kitcher, explanations are arguments relating premises to a conclusion that is to be explained, but the arguments must also be unified. The form of an argument used to explain one explanandum should be the same form that explains lots of other explananda as well. With this added focus upon unification, Kitcher believes that the problems like the flag-pole are avoided, since the most unified argument-forms will not be of the type that include shadow-lengths as explanatory premises. However, Skow (2006) rejects Kitcher’s unificationist project because what makes an explanatory theory unifiable is something about how it answers why questions, not that it makes possible the collection of many phenomena under the same form of argument. 4.3.1.2 Explanations in Science: Causes explain Effects What is commonly taken to be missing from the explanations-as-arguments approaches is that they do not account for the role of causality. Bertrand Russell believed that fundamental physics had moved beyond talking about the world in causal ways, and as such it was an unneeded concept. The baby was thrown out with the bathwater, though, as Nancy Cartwright (1979) argued that causation is relevant when searching for effective strategies for intervention, like trying to figure out how to mitigate the risks of heart disease given that it can be caused by smoking. Causation, Cartwright argues, lays a real-world foundation that cannot be reduced to probabilistic laws that merely state a correlation between phenomena (pp. 421-422). 104 Since then, causation has been the central focus for most recent theories on scientific explanation (e.g. Salmon, 1984; Woodward, 2003; Pennock, 2006; Strevens, 2008). Attempts to retain space for non-causal explanations have been rejected (Skrow, 2016), and while arguments have been advanced that probabilistic explanations are not causal (Railton, 1981), more recent theories have retained an account of probabilistic explanations as causal explanations (Strevens 2008, p. 336). On these accounts, explanations are constructed that explain effects by virtue of their causes. Constructing an explanation, then, is the act of selecting an effect phenomenon and situating it within the causal structure that produces it. When our causal framework is something simple to model, like cause (C)  effect (E), it is a trivial matter to construct a causal explanation. For instance, in an effort to counterbalance the countless hypothetical vases and windows that have been broken in discussions about causality, consider a clay vase that is placed in a kiln and fired. We would explain why the vase became hard and glossy by pointing to the firing process within the kiln as the cause of the transformation, thus yielding a relatively simple cause and effect relationship. Counterfactually, had the vase not been placed in the kiln, or had the kiln not been plugged in, or had the kiln’s temperature been set too low, the clay would not have become glossy and hard. If we want an explanation of a phenomenon, we could look to understand how it was brought about by its causes. Salmon’s (1984) Causal Mechanical (CM) model looked to avoid issues like the flag pole shadow problem by pointing to “marks” that are transmitted through causal processes. The shadow of the pole does not transmit its causal mark through the process when its features are altered, though altering the pole’s features would transmit a mark through the shadow. However, 105 Salmon’s account becomes increasingly unwieldy with complex explanations, and as such will not serve our need for an explanation that can handle deep explanatory complexity. Let us briefly return to the earlier example of firing a clay vase in a kiln. Our causal story about the transformation of the clay could become much more complex, of course. We might go down a level, and instead of focusing on the heat’s effect upon the clay as a single entity, we might explicate the casual web with more detail. Instead of merely noting the macroscopic change to the clay vase as a whole (it becomes hard and glossy), we might highlight the physical changes occurring at the molecular level. The energy from the heat causes the molecules of clay to undergo a chemical reaction. The kiln’s production of sufficient heat causes the chemical transformation within the clay, converting its constituent chemical components into new aggregations and arrangements. We might also go into more detail by looking at the kiln as a compound set of entities and processes. A button is pressed, which through a system of engineered mechanisms allows the kiln to draw electricity from the wall socket it is plugged into in order to power the internal furnace that transforms electrical energy into heat, which is regulated at a constant temperature through other feedback mechanisms. Even in seemingly simple causal relationships, identifying causes can easily become complex and requires judgment about how to identify the causally- relevant elements of the complete causal web. Complex casual systems pose a significant challenge to any causal explanation that needs to point to relevant causes, and the recent task for philosophers is to come up with a solution for the intricate causal connections of complex phenomena. If a causal explanation needs to point to every cause in its causal network, this quickly becomes unrealistic. Providing causal explanations, then, becomes a task of identifying the most causally relevant parts of a causal 106 network. Woodward (2003) lays out and defends an interventionist account of causation and causal explanation, according to which we can use interventions to manipulate a causal system in our attempt to pin down and understand the underlying causal relationships. Once we have an accurate understanding of the causal structure of the system, we can then use it in constructing causal explanations. Strevens (2008) follows this approach in his kairetic account of explanation, which by focusing on difference-makers attempt to “distill” an explication of a causal network down to the explanatorily relevant factors (pp. 69-71). These accounts are theoretically robust, but burdensome in practice for the task of constructing actual scientific explanations with huge causal webs, such as the complex evolutionary history that has contributed to the evolution of morality, itself a complex phenomenon. The task for any causal explanation of a complex system is to figure out how to move from the overwhelming complexity of causal relationships towards explanations that help us understand the phenomenon. For instance, some recent arguments have been put forth to move beyond the causal model, arguing that idealizations in models can produce better explanations (Batterman, 2010) and that optimality models can provide explanation without representing all of the difference-making causes (Rice, 2012; Rice, 2015). Rice notes, though, that such optimality models need not be non-causal (2015, p. 590). Another strategy to tackle complexity while still explicitly preserving the causal relationships at the heart of the phenomena is to use pragmatic considerations to facilitate the construction of an explanation within a complex causal system. Clark (1998) argues against the “myth” of explanatory equality, which he describes as If the overall causal web is complex yet x is to be cited as the cause of y, then x must be the factor that does the most actual work in bringing it about than y. Causal equality, by contrast, implies explanatory equality. (p. 81) 107 Clark dispels this myth by focusing on a difference between explanations-how and explanations-why. If we want an explanation of how something came about, we would need to account for “the full intricacies of the woven whole,” (p. 95), but if instead we want to narrow our question to a “why some particular difference of interest,” then we can selectively point to a cause of that difference of interest even if in reality that cause is sharing the causal burden with one or many more other causes (pp. 92-95). In a sense, this approach lets us reduce the would-be causal contributors of our explanation in a way that lets us highlight the contributions of one factor that is particularly causally relevant in one context compared to other conditions. This strategy, which Clark limits to instances where a causal factor in one setting has a different effect in another setting, thus making the difference the feature that lets us grant explanatory priority to one of the causes, is similar to the pragmatic CaSE approach proposed by Pennock (2006). 4.3.1.2.1 The CaSE Model of Causation: The Twine to Bind Pennock (2006) advocates for the CaSE model of explanation. It seeks to find a middle ground between (1) the traditional way in which we simplify casual events into two-part relationships that link a cause (C) to its effect (E) and (2) the multiple independent relevant variables (MIRVed) approach, which treats the antecedent of the causal relationship as a compound that includes the complete collection of multiple independent relevant variables (pp. 412-413). The traditional (1) is too simplistic to achieve causal accuracy, while the MIRVed approach (2) is impractical and unwieldy. This would be especially true for evolutionary explanations, given their focus on adaptive traits, which are the products of a gradual and iterative causal process wherein the frequency of such a trait within a population is likely to 108 increase across generations until it reaches a fixation equilibrium, since the trait confers a reproductive advantage upon its bearers As an alternative, Pennock’s CaSE model of causation retains the practicality of (1) while allowing for the complexities of (2). It does so by introducing a pragmatic element to causal explanation as we identify a Condition (C) in a Situation (S) that causes Effect (E). In this way The CaSE model thus makes explicit that it is actually a combination of factors that causes an effect and it also allows us to isolate a particular factor that is of special interest, as we commonly do in ordinary causal talk. What we label “the cause” from among the multiple causal conditions is a salient factor that we choose to highlight because, for instance, we take it to be the triggering factor in standard background conditions or because of our particular interest at the time. (pp. 413-414) The CaSE model requires (and allows) us to organize the complex causal web of reality into a cause and the conditions, based on pragmatic considerations. Imagine a scenario wherein a skydiving accident, wherein due to an incompletely deployed parachute, a skydiver crashes into the ground at a high velocity and sustains serious injuries. A web of causal interactions has produced an effect, (E), in this case the injured skydiver. How we parse all of the causal elements into the conditions and the cause depends on our pragmatic interest in the scenario. Medical professionals on the scene are likely to view the cause in relation to the sort of interventions they can apply to ameliorate the effect. Treating the wounded skydiver requires recognizing the way in which the body decelerated far too rapidly, resulting in broken bones, bruised organs, internal bleeding, and other conditions to be treated (as Douglas Adams playfully notes, “It’s not the fall that kills you; it’s the sudden stop at the end”). The injuries are caused by the blunt force trauma of the collision. Alternatively, an accident investigator will look to explain the injured skydiver with a very different sort of explanation, typically one that tries to assess responsibility for the action (was the equipment faulty or did the skydiver fail to follow the appropriate protocols?). The accident investigator will entirely ignore the physiological harms that occurred during the 109 sudden deceleration, leaving those as part of the background conditions of the situation, (S). Instead, the accident investigator will point to the bag lock that prevented the main parachute from deploying properly, thus identifying a faulty bit of equipment as the cause (C) which explains why the skydiver was injured (E). Pragmatics steer how we identify the salient cause from amongst all of the background conditions that also play a causal role (like the weight of the skydiver, gravity, air pressure, terminal velocity, etc.). The CaSE model provides us with a model of causation that allows us to specify explanations for a world that is a complex web of intersecting causal processes converging one upon another and diverging again at points throughout space-time. There are other important features of the causal relation (for example, that it involves production and propagation, and that it has an important asymmetry, that it licenses certain inferences) but for our purposes here the critical feature is its web structure — multiple causal factors are required to produce an effect or effects, and those factors themselves are effects with multiple causes. (p. 412) Morality, as described above, is certainly just such a complex web of entangled causal processes. The many causal processes involved in the evolutionary view of morality are thoroughly intertwined, and this complexity is captured in the view that (some) human behaviors “are actually 100% cultural and 100% genetic” (Henrich & Henrich, 2006, p. 224). Adopting the CaSE model of explanation allows us pragmatically investigate pieces of the complex causal web that I have identified as morality-as-explanandum. It also accounts for how multiple disciplines can fruitfully tackle different pieces and different levels of the phenomenon, by holding different parts of the web constant as the background conditions while focusing on providing an explanation of one piece of interest. In this way, the plants of the Entangled Bank can be braided and bound together with the twine of the CaSE model. 110 4.4 Applying the CaSE Model to Evolutionary Explanations of Morality Using the CaSE model, we are now in a position to see how it may be possible to unify evolutionary explanations from the three disciplines I have identified by seeing them as offering explanations that highlight different pieces of the causal web. Imagine that we would like to explain fairness from an evolutionary perspective. The causal web of morality, which contains all of the possible explanans—causal facts and events that could contribute to an evolutionary explanation—is vast, and we could never hope to give a causal explanation that identified all causally-contributing (or “difference-making”) factors at the same time. Especially when we consider the evolutionary origins of the biological building blocks of morality, which were causally produced across thousands of years as natural selection favored variations of those building blocks that contributed positively to adaptive success and gradually increased in frequency within the population. No MIRVed causal account could ever hope to account for all of the causal interactions that occurred as part of an evolutionary story about a particular trait. Fortunately, by applying the CaSE model, we can construct causal explanations that are practical while still respecting the deeply complex causal reality that includes innumerable causes and interactions all causally interwoven over a long evolutionary history to account for a particular phenomenon of interest. As an example of how we might go about using the CaSE model to provide an evolutionary explanation of some morally-relevant phenomenon, let us consider the question “why do humans care about fairness of distribution?” to be interpreted in different ways that hold constant some aspects of the situation in order to construct an explanation the emphasizes other aspects. 111 All of the approaches are assuming that there is one underlying causal reality that would account for the evolution of fairness considerations. In this way, all three approaches are working within the same complex causal web of evolutionary history that includes, among many other things, mental architectures, psychological processes, cultural elements, phylogenetically related species bound by shared common ancestry, the processes of genetic variation, heritability, and selection, and many other elements. The causal interactions of all of these elements fits together in some unknowably complex way to give rise to our disposition for fairness in distribution. If we start with ethology, an ethologist will interpret an evolutionary-why question about human behavior as an opportunity to set aside the various causal aspects of human societies like brains, dispositions, and cultural values, to instead focus their interest onto the deeper evolutionary past: the part of the causal web that involves the common ancestry of a possibly evolved disposition for fairness. The explanation, then, becomes one about the behaviors of primates, and by pointing to the presence of a “sense of fairness” in non-human animals, it is offered along with the evolutionary process that bestowed this capacity or instinctual preference onto the common ancestors of humans and other primates. This shared history part of the causal web explains, at least in part, the human preference for fairness. And we see ethologists offer just such explanations, such as when de Waal notes how capuchin monkeys in experimental settings who were given a lower-value food reward relative to their partners for performing the same task registered their displeasure with increased negative behaviors (p. 44-49). de Waal notes that these monkeys do not a have a full sense of human fairness, but “the full blown sense of fairness must have started someplace” (p. 49). Human fairness is explained, at least in part, by the comparative ethological approach of demonstrating that shared behavioral trait (or in this case, a close precursor to a trait) is a derived 112 characteristic that evolved in a common ancestor and is shared in all the species downstream of the trait on the phylogenetic tree, including capuchin monkeys, primates, and humans. For a complete understanding of the human predisposition for fairness, the ethologist gives an explanatory account that says such a behavioral tendency is caused by the biological underpinnings of a behavioral trait that can be found as a gradient spanning across our closest evolutionary kin. To fully understand ourselves, we look to that “bottom-up” (see Chapter 3) approach preferred by ethologists like de Waal who illuminate our human nature by placing psychological processes and motivations (evolutionary psychology) and fitness evaluations of behaviors (evolutionary game theory) as part of the assumed causal situation, S, holding those things as causally operational but unconsidered background conditions, much like the emergency room staff places causal elements like wind resistance, terminal velocity, and faulty equipment into the situation, S, which they could bracket as given when trying to understand the injuries sustained by the skydiver. In this way, the ethologists focus their explanations and their efforts upon the biologically-basis of animal behavior and the way it is distributed across the phylogenetic organization of animal life. The building blocks for fairness in distributions evolved in some common ancestor that links capuchins, apes, and humans, because behaviors that preserved fairness offered an evolutionary advantage, and those building blocks have been built upon by our increasingly complex mental capacities and culture. Nevertheless, understanding those initial building blocks enriches our understanding of our current capacities and tendencies. In evolutionary psychology, if there is to be an evolutionary explanation of fair distribution behavior, it will have to identify the innate mental architecture that, in conjunction with reasoning and cultural considerations, gives rise to a sense of fairness and facilitates 113 behaviors about fair distribution. One such study (Sloane, Baillargeon, and Premack, 2012) found that 21-month-old infants expect individuals to be rewarded for their efforts and are capable of detecting a violation when a “worker” and “slacker” are rewarded evenly. The explanation for such a feature being present in children so young is that it is likely an evolved innate mechanism (or set of mechanisms) designed to facilitate normative behaviors that improve sociability and contributed to improved survival in ancestral environments. Haidt and Joseph (2006) identify a similar innate intuition for reciprocity, which likely evolved as a solution to cooperative opportunities with non-kin as a means to identify cheaters and cooperators, and has since been repurposed by our cognitive capabilities and current cultural environment to serve as an affective intuition during judgments of fairness or justice (see Table 1, p. 382). In this way, given their research interest, the pragmatic elements, “a,” of the CaSE model allow evolutionary psychologists to bracket off the evolutionary history of this innate intuition that traces its ancestral building blocks on a phylogenetic pathway from a shared common ancestor through all the species past and present with whom we share a branch that contains this derived trait. The psychologists focus on the present innate architecture of human minds, and focus their causal explanations and difference-making investigations upon this causally-relevant part of the evolutionary causal web. Similarly, evolutionary psychologists bracket the fitness tests of the psychological mechanism, as while an important part of the causal evolutionary story about how natural selection produced the mechanism in question, it remains outside the purview of psychological investigation. An evolutionary game theorist viewing the explanandum of fair distribution will hold the causal aspects of the web about common ancestors and mental architecture as causally operational parts of the situation, S, while identifying game theoretic models of a fair distribution 114 strategy as the cause, C. Instead, an evolutionary game theorist looks at the percentage of simulated trials that see a strategy for fair distribution propagate to a fixed equilibrium, thus providing a how-possibly explanation that emphasizes the adaptive fitness of such a behavior. For instance, Alexander (2007) constructs a lattice model where the simulated players can demand a variable amount of resources (anywhere from 0 to 10) during opportunities for exchange with another player, and across multiple generations fair distribution (“demand 5”) strategies are able to invade into regions of other strategies, rendering them unstable and stabilizing the fair distribution strategy, the speed (number of generations) of which causally depends on aspects of the model (pp. 165-173). Thus, a propensity for fair distribution, whether it turns out to be a genetically based intuition, an entirely cultural norm, or some interplay between the two, is the distribution strategy that has the best adaptive fit and can be selected for by natural selection. Having a behavioral strategy for fairly sharing resources causes benefits to the fair-sharers that result in that strategy moving to fixation within a population. Thus, each of these approaches is able to engage the same messy, entangled causal web of evolutionary history but selectively ropes off parts of the causal story to leave in the causal situation, S, while pragmatically demarcating what entities and processes will constitute the cause C that, in situation S, produces the explanandum. In this way, the three evolutionary approaches I have considered can be integrated into a fuller, more robust causal explanation of morality-as-explanandum by offering explanations that highlight different causally relevant features of the complex causal web, and each of these causally relevant causes explain, at least in part, the same explanandum. In this way, the CaSE model allows for the integration of explanatory practices that are explaining different parts of the causal web, the combination of which provides a more robust and complete understanding of the explanandum. The integration 115 of explanatory approaches into a more robust causal understanding of the explanandum is just one benefit of the pluralistic explanation afforded by the CaSE model, but additional benefits could result from further unifying the research programs into an interdisciplinary program. This benefit is explored in the following section. 4.5 A CaSE for Interdisciplinarity An interdisciplinary research program is more than just a multidisciplinary research program, namely in that it brings together multiple disciplines, integrating inputs from each . Though it requires substantial effort and investment to establish productive interdisciplinarity, doing so offers tantalizing benefits. Formally pursuing greater interdisciplinarity in the pursuit of evolutionary explanations of morality might be worthwhile, and a champion of this cause could seek to unite the research efforts of interested psychologists, ethologists, and game theorists. Something like this could bring together evolutionary researchers from across disciplines who are interested in morality, and they could be given an opportunity foster improved communication and collaboration. 4.5.1 Collaborative Integration Can Strengthen Research against Would-Be Weaknesses Approaches from evolutionary psychology and the cognitive sciences give us potential insights into the roles of mental mechanisms when individuals make moral judgments. This work can help illuminate what motivations lead individuals to make judgments. Given the conception of morality-as-explanandum we are after, this is an important part needed to robustly understand or explain morality. What critics of evolutionary psychology may be keen to point out, however, is that such studies can be subject to the criticism of adaptationism, charging the evolutionary 116 psychologist with merely telling a “Just-So” story that, while convenient, is a wholly unjustified interpretation (explanation) of the phenomena observed. Here, I think, forging a connection between game theory approaches and evolutionary psychology would make each approach more robust. Game theory approaches attempt to demonstrate that various behaviors can emerge and remain evolutionary stable, resistant to invasion by other strategies. What the evolutionary game theory approaches cannot do is say much, if anything, in the way of a programmed agent’s psychological motivations. Furthermore, critics can charge game theory approaches with “merely” demonstrating a how-possibly account that explains the presence of a behavioral norm (it is an evolutionarily stable behavioral rule within the confines of this modeled environment), but that such an account cannot claim much about an actual history of the motivation of agents to act in that way. However, if sufficient connections can be forged between the descriptive understanding of human moral judgments provided by evolutionary psychology and an evolutionary game theoretic model, then the connection between the two types of approaches would help give a more robust explanation that avoids some of the key critiques leveled against the disciplines individually. Can such a bridge be built into the practices of evolutionary research? From a theoretical perspective, unifying the two approaches seems necessary to developing a more robust account. Furthermore, empirical approaches in evolutionary psychology explicitly limit their focus to human subjects (since, for instance, these are the sorts of subjects that can provide an account of their reasoning for making a particular judgment). The deeply enmeshed causal web of both biological and cultural elements that may have contributed to the observed behavior can make it difficult to assert explanations that appeal to underlying biological mechanisms that contributed to the behavior. Animal ethology can, in some cases, provide a tool to resolve this causal 117 underdetermination.53 The gradualism of Darwinian evolution gives us reason to believe that, generally, the biological building blocks of morality stretch across our evolutionary past in a gradient, present in lesser degrees as we move backwards through our evolutionary ancestors. Given this, connecting the insights from evolutionary psychology and neuroscience to the insights from primatology and other branches of ethology might help to provide additional reasons to believe (or doubt) that the mechanism under analysis is in fact biologically based within the human process, since the ethological case serves as a “culture-free”54 control group for comparison. This strategy would help give us a more complete evolutionary picture of morality. In instances where we want to focus on the biological components of human morality, their entanglement with the cultural aspects of the human experience can obscure our ability to talk about such features. Identifying these biological components (or at least the closest available homologue) in non-human animals increases the confidence with which we can ascribe biological roots to those components in humans. 4.6 Conclusion Evolutionary insights have radically improved our ability to understand (explain) the natural world around us, including how we understand ourselves and our relationship to the rest of the natural world. For the past century and half, evolutionary arguments have been advanced that have looked to explain human morality as a feature of our biological origins, as a capacity or 53 Underdetermined only in the sense that researchers lack sufficient knowledge about the underlying casual system to arrive at an explanation. 54 There is ample evidence to support the idea of culture in a variety of animal societies. Here by “culture-free” we might mean a culture that is substantially less than our own. We might even acknowledge an inverse relationship: the less culture an animal group possess, the stronger they might serve as a comparative “control” for inferencing about humans (though there is likely a point where the difference is substantial enough that the cases are incommensurable). 118 propensity endowed to us by our evolutionary history. While early attempts waded too greedily into the problematic domain of evolutionary ethics, this did not dissuade recent research programs within psychology, ethology, and game theory from offering evolutionary explanations of morality, albeit with a more nuanced sensitivity to avoid the naturalistic fallacy by making sure not to conflates the identification and description of biological foundations for behaviors with the prescriptive justification of those behaviors. The prolific efforts of these researchers, concentrated especially over the past two decades, has resulted in an impressive literature about the evolution of morality. It is unclear how, if at all, these research programs could fit together into a coherent explanation of morality, though there is a tendency in the literature to find assumptions of a presumed moral synthesis that would (or at least could) connect these research endeavors in a meaningful way. This was the task I set out to accomplish. First, I looked for a reportive account of morality-as-explanandum, to see if there was reason to think that the explanations being proposed by these different research programs were ostensibly aiming to explain the same phenomenon. As it turns out, I found evidence of sufficient overlap in how the evolutionary approaches conceived of morality, namely that it is a phenomenon that includes social interactions that involve behaviors often relevant to helping and hurting others, and the perception and response to these interactions involves the stimulation of an affective moral sense that is combined with rational cognitive processing and consideration of cultural elements such as values, norms, or expectations of approval or disapproval during moral judgment. While the research programs of evolutionary psychology, ethology, and evolutionary game theory are attempting to explain the same phenomenon when they talk about morality, it 119 was not readily apparent how the different kinds of explanations could fit together, if at all. For those who adopt a unity of science view, there is a tendency to prefer explanatory reductionism or explanatory eliminativism that identifies the preferred mode of explanation and removes others. On the other hand, pluralistic approaches to explanation allow for multiple modes of explanation to account for the same phenomena. After considering the kinds of explanations that each of the three evolutionary approaches offers, including what they try and explain and by virtue of what explanatory features, I demonstrated that Pennock’s CaSE pragmatic model of causation could be used to demonstrate that in principle the explanations of each approach could be integrated. Pluralistically weaving the explanations of each approach together yields a more robust and complete account of the causal web that has, collectively, produced our biological capacities for morality. Beyond the in principle integration of parts of the causal web into a more complete whole, integrating the approaches also helps to insulate the explanatory claims of each from some its more pressing objections. For instance, while evolutionary psychology is susceptible to critiques of adaptationism, by demonstrating that the behavioral building blocks of the proposed innate psychological intuition can be found in our phylogenetic neighbors gives reason to think that the trait has an adaptive function and has been preserved by selective pressures. Similarly, game theoretic approaches can demonstrate via models that the behavioral tendency is, in fact, adaptive and causally advantageous to reproductive success. Given this, some exciting prospects for future work exist. First, a more thorough exploration of how the research programs of evolutionary psychology, evolutionary game theory, and ethology could be meaningfully unified into interdisciplinary research projects is warranted. It is possible that such interdisciplinarity might reveal new fruitful research questions to 120 investigate or test. Many practical challenges exist for any interdisciplinary effort, but the potential promises of such collaboration may warrant it. Second, there is an interesting question of how to connect a robust evolutionary explanation of morality to a philosophical account of the moral domain. As I hinted in Chapter 2, I believe there is a compelling case to be made for using insights about the biological capacities of our moral judgment to inform our philosophical positions about morality. While the naturalistic fallacy presents a hurdle to such endeavors, I do not believe it is necessarily an intractable problem and hope to investigate this issue more deeply in the future. Third, while the possibility for pluralistic explanatory integration between the research fields has been demonstrated in principle, the issue of confirmation still remains. 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