As part of the “Profiles in Evolutionary Moral Psychology” interview series, This View of Life had the opportunity to speak with Oliver Scott Curry. Dr Curry is Departmental Lecturer at the University of Oxford’s Institute of Cognitive and Evolutionary Anthropology, as well as Research Associate at the London School of Economics’ Centre for Philosophy of Natural and Social Science. His research has focused on altruism and cooperation in contexts such as kinship, social networks, and friendship, and in relation to topics such as patience, humour, and theory of mind. In his interview, Curry explains why David Hume is the founder of evolutionary psychology, why social constructivists are really just evolutionary psychologists who got carried away, and why nothing about morality makes sense except in the light of evolution.MICHAEL PRICE: What can evolutionary approaches tell us about human moral systems that other approaches cannot tell us? That is, what unique and novel insights about morality does an evolutionary approach provide?OLIVER SCOTT CURRY: Well, everything. It can tell us what morality is, where it comes from, and how it works. No other approach can do that.The evolutionary approach tells us that morality is a set of biological and cultural strategies for solving problems of cooperation and conflict. We have a range of moral instincts that are natural selection’s attempts to solve these problems. They are sophisticated versions of the kind of social instincts seen in other species. These instincts motivate us to be social, cooperative, and altruistic, and they provide the criteria by which we evaluate the behaviour of others. And ever since entering the cognitive niche, humans have attempted to improve on nature’s solutions by inventing new rules and tools for social life.The evolutionary approach also gives us a rich deductive theory about what kinds of morality to expect. Evolutionary game theory tells us that there are many different problems of cooperation and many different solutions. These problems (and their solutions) include: (1) the allocation of resources to kin (love, altruism, family values, and the prohibition of incest); (2) coordination to mutual advantage (teamwork, loyalty, perspective-taking, and conformity); (3) social exchange (trust, gratitude, reciprocity, revenge, guilt, and forgiveness); and (4) conflict resolution through (a) contests (bravery, generosity, and humility); (b) hierarchy (deference, respect, obedience, benevolence, and “noblesse oblige”); (c) division (equity, merit, and fairness); and (d) property (respect for prior ownership and territory). The theory tells us to expect not one monolithic moral sense or a simple combination of desires and beliefs but rather a vast Periodic Table of Ethics.Above all, the evolutionary approach demystifies morality and brings it down to earth. It tells us that morality is just another adaptation that can be studied in the same way as any other aspect of our biology or psychology. This is a huge contribution. Of course, the theory may turn out to be wrong to a greater or lesser degree, but it is by far the best we have.PRICE: The ordinary view in biology is that adaptations evolve primarily to promote individual fitness (survival and reproduction of self/kin). Do you believe that this view is correct with regard to the human biological adaptations that generate moral rules? Does this view imply that individuals moralize primarily to promote their own fitness interests (as opposed to promoting, e.g., group welfare)?CURRY: No. Adaptations evolve to promote the replication of genes; natural selection cannot work any other way. Genes replicate by means of the effects that they have on the world; these effects include the formation of things like chromosomes, multicellular individuals, and groups. (My understanding is that everyone agrees about this, although there is some debate about whether groups are sufficiently coherent to constitute vehicles [1].) Thus, far from being opposed to groups, the gene-centred view explains why some kinds of groups form and persist – families, coalitions, and hierarchies. After all, what is a group but a collection of cooperating individuals? From this perspective, individuals moralize in order to promote and maintain cooperation (which redounds, ultimately, to the benefit of their genes). This often, but not always, promotes their own interests and those of other members of the group. But note that, whereas evolutionary theory makes clear what constitutes a benefit to a gene – replication – it is not at all clear what constitutes a benefit to an individual (let alone a group).PRICE: What work by others on the evolution of morality (or just on morality in general) have you found most enlightening?CURRY: David Hume’s work has been particularly inspiring. In many ways he is the great-great-great granddaddy of evolutionary psychology. He almost stumbled upon the theory of evolution. He undertook a comparative “anatomy of the mind” that showed “the correspondence of passions in men and animals.” His “bundle theory of the self” hints at massive modularity. His A Treatise of Human Nature [2] introduced “the experimental method of reasoning into moral subjects,” and discusses relatedness, certainty of paternity, coordination and convention, reciprocal exchange, costly signals, dominance and submission, and the origins of property. He even anticipated by-product theories of religion, describing religious ideas as “the playsome whimsies of monkies in human shape” [3]. Remarkable.When trying to understand human moral psychology, the work of Darwinians such as George Williams, Bill Hamilton, Robert Trivers, Richard Dawkins, Helena Cronin, and especially John Maynard Smith has been essential to grasping the underlying mechanics of evolution and the strategic aspect of social interaction [4-9]. Every social scientist should be locked in a room with a textbook on game theory for at least a week [10]. And the work of John Tooby and Leda Cosmides [11] and cybernauts like Rodney Brooks [12] has illuminated what kinds of things psychological adaptations might be and how to look for them. (A friend of mine once said that he found Leda’s paper on social exchange more enlightening than all the moral philosophy he had ever read.)When trying to make sense of standard social science (and engineer a rapprochement with evolutionary psychology), two books have been a revelation. I never really understood what the social sciences were all about until I read Convention [13] and The Social Construction of Reality [14]. Now I get it. According to the original theory, social constructions are shared expectations of behaviour that are used to solve coordination problems. That’s it. I think evolutionary psychologists and social constructionists can be friends in the sense that an understanding of evolved social motives and adaptations like ‘theory of mind’ can help explain why and how some things are socially constructed. The social constructionists err only when they get carried away and start thinking that everything is a social construction. As George Williams would say, “Social construction is a special and onerous concept that should not be used unnecessarily.”Most recently, I’ve found work on the role of theory of mind in social interaction and morality [15-17] and on cultural transmission and cooperation [18-21] to be mind-expanding and very exciting.PRICE: Which of your own publications are most relevant to an evolutionary understanding of morality? Which results or ideas from your work do you regard as most significant?CURRY: My PhD thesis pulled together a lot of disparate material on the evolution of cooperation, and showed how it could provide a coherent framework for morality that made sense of much of moral philosophy [22]. One spin-off paper from the thesis argued that conflict resolution was an overlooked domain of cooperation that could account for many of our otherwise peculiar ideas about moral virtues – the virtues of the hawk and the virtues of the dove [23]. Another showed that the naturalistic fallacy is widely misunderstood and nothing to be afraid of – or rather, it does not present an obstacle to a fully naturalistic account of ethics [24]. (On the contrary, Hume’s famous is-ought paragraph is actually an argument in favour of a naturalistic ethics rooted in the passions.)Since then, my empirical work has tried to open up new areas of cooperation, with forays into patience, coalitions, coordination, and friendship. I’m currently using this broader framework to conduct a large cross-cultural survey of moral values, and I hope to have some exciting results to report soon.The overall message is that there’s more to morality than kinship and reciprocity, and evolutionists should make use of all the available theories when trying to explain ethics.PRICE: What are the most important unsolved scientific puzzles in evolutionary moral psychology?CURRY: The questions that keep me up at night include:• If reciprocal altruism is so simple, why is it so rare?• Why are people so quick to divide the world into “us and them”? Why not just have a bigger us? (I’d like to see an answer rooted in three-player game theory.)• To what extent are the distinct types of cooperation solved by distinct mechanisms, as opposed to a shifting constellation of mechanisms? For example, is sympathy one thing (that solves lots of problems) or is it a catch-all term for several different things?• Why do we care how other people treat other people? Why do we care if B is unfair to C, or if D commits incest with E? Is it a by-product of having evolved in small groups, do I have a strategic interest in others’ behaviour, or is it something else? (I know that there are some very clever people working on this, and I look forward to having the complete answer.)• Is purity really a moral domain, or is disgust just a generic response to lots of things we don’t like? (Ditto.)• How does the evolutionary approach make sense of political values such as justice and rights?• Do we have a separate set of moral instincts for dealing with cooperation between groups?• Is there an intrinsic link between religion and ethics, or is it just a temporary historical contingency like the link between religion and cosmology?• And finally, James Laidlaw has said that “ethics” is the question (“how should I live?”), and “moral” is but one answer [25]. What other answers are there?Answers on a postcard please!LinksOliver’s Scott Curry’s personal pageBibliography1. Dawkins, R., Burying the Vehicle. Behavioral and Brain Sciences, 1994. 17(4): p. 616-617.2. Hume, D., A Treatise of Human Nature1739/1985: Penguin Classics.3. Hume, D., The Natural History of Religion1757/1889, London: Freethought.4. Dawkins, R., The Selfish Gene. 3rd ed1976/2006, Oxford: Oxford University Press.5. Williams, G.C., Adaptation and Natural Selection: A critique of some current evolutionary thought1966, Princeton, New Jersey: Princeton University Press.6. Hamilton, W.D., The evolution of altruistic behavior. The American Naturalist, 1963. 97: p. 354-356.7. Trivers, R.L., The evolution of reciprocal altruism. Quarterly Review of Biology, 1971. 46(1): p. 35-57.8. Axelrod, R. and W. Hamilton, The evolution of cooperation. Science, 1981. 211: p. 1390-1396.9. Cronin, H., The ant and the peacock1992, Cambridge: CUP.10. Dixit, A. and S. Skeath, Games of Strategy1999, New York: W W Norton & Company.11. Barkow, J.H., L. Cosmides, and J. Tooby, eds. The Adapted Mind: Evolutionary psychology and the generation of culture. 1992, Oxford University Press: New York. 666.12. Brooks, R.A., Cambrian Intelligence: The early history of the new AI1999, Cambridge, Massachusetts: MIT Press.13. Lewis, D.K., Convention: a philosophical study1969, Cambridge, Massachusetts: Harvard University Press.14. Berger, P.L. and T. Luckmann, The Social Construction of Reality1966, London: Allen Lane The Penguin Press.15. Saxe, R. How we read each other's minds. TED Talks 2009; Available from: Tomasello, M., et al., Understanding and sharing intentions: The origins of cultural cognition. Behavioral and Brain Sciences, 2005. 28(5): p. 675-+.17. Young, L., et al., The neural basis of the interaction between theory of mind and moral judgment. PNAS, 2007. 104(20): p. 8235-8240.18. Henrich, J. and R. McElreath, The evolution of cultural evolution. Evolutionary Anthropology, 2003. 12(3): p. 123-135.19. Boyd, R., P.J. Richerson, and J. Henrich, The cultural niche: Why social learning is essential for human adaptation. PNAS, 2011. 108: p. 10918-10925.20. Pinker, S., The cognitive niche: Coevolution of intelligence, sociality, and language. Proceedings of the National Academy of Sciences of the United States of America, 2010. 107: p. 8993-8999.21. Boyd, R. and P.J. Richerson, Culture and the evolution of human cooperation. Philosophical Transactions of the Royal Society B: Biological Sciences, 2009. 364(1533): p. 3281-3288.22. Curry, O.S., Morality as Natural History: An adaptationist account of ethics, in Government2005, London School of Economics: London.23. Curry, O.S., The conflict-resolution theory of virtue, in Moral Psychology, W.P. Sinnott-Armstrong, Editor 2007, MIT Press: Cambridge, Massachusetts. p. 251-261.24. Curry, O.S., Who's afraid of the naturalistic fallacy? Evolutionary Psychology, 2006. 4: p. 234-247.25. Laidlaw, J., For an Anthropology of Ethics and Freedom. The Journal of the Royal Anthropological Institute, 2002. 8(2): p. 311-332.