Bringing in Darwin: Evolutionary Theory, Realism, and International Politics

Bringing in Darwin Bradley A. Thayer Evolutionary Theory, Realism, and International Politics Efforts to develop a foundation for scientiªc knowledge that would unite the natural and social sciences date to the classical Greeks. Given recent advances in genetics and evolutionary theory, this goal may be closer than ever.1 The human genome project has generated much media attention as scientists reveal genetic causes of diseases and some aspects of human behavior. And although advances in evolutionary theory may have received less attention, they are no less signiªcant. Edward O. Wilson, Roger Masters, and Albert Somit, among others, have led the way in using evolutionary theory and social science to produce a synthesis for understanding human behavior and social phenomena.2 This synthesis posits that human behavior is simultaneously and inextricably a result of evolutionary and environmental causes. The social sciences, including the study of international politics, may build upon this scholarship.3 In this article I argue that evolutionary theory can improve the realist theory of international politics. Traditional realist arguments rest principally on one of two discrete ultimate causes, or intellectual foundations. The ªrst is Reinhold Niebuhr’s argument that humans are evil. The second is grounded in the work Bradley A. Thayer is an Assistant Professor of Political Science at the University of Minnesota—Duluth. I am grateful to Mlada Bukovansky, Stephen Chilton, Christopher Layne, Michael Mastanduno, Roger Masters, Paul Sharp, Alexander Wendt, Mike Winnerstig, and Howard Wriggins for their helpful comments. I thank Nathaniel Fick, David Hawkins, Jeremy Joseph, Christopher Kwak, Craig Nerenberg, and Jordana Phillips for their able research assistance. Finally, I wish to acknowledge the generous support of the Earhart Foundation, and Ingrid Merikoski and Antony Sullivan in particular, and the University of Minnesota, which allowed me to complete my research. 1. See Edward O. Wilson, Consilience: The Unity of Knowledge (New York: Knopf, 1998). 2. Wilson has pursued this goal since 1975, most recently in ibid., pp. 8–14, 197–228; Roger D. Masters , “The Biological Nature of the State,” World Politics, Vol. 35, No. 2 (January 1983), pp. 189–190; and Albert Somit, “Human Nature as the Central Issue in Political Philosophy,” in Elliott White, ed., Sociobiology and Human Politics (Lexington, Mass.: D.C. Heath, 1981), pp. 167–180. 3. Ethology—the study of animal behavior—is signiªcant as well, particularly the concept of evolutionary stable strategies, which was introduced by J. Maynard Smith and G.R. Price, “The Logic of Animal Conºict,” Nature, November 2, 1973, pp. 15–18. This has informed such important scholarship as Robert Axelrod and William D. Hamilton’s ªnding of the importance of reciprocation or tit-for-tat strategies for cooperation. See Axelrod and Hamilton, “The Evolution of Cooperation,” Science, March 27, 1981, pp. 1390–1396; Robert Axelrod, The Evolution of Cooperation (New York: Basic Books, 1984), chap. 3; and John Maynard Smith, Evolution and the Theory of Games (New York: Cambridge University Press, 1982). International Security, Vol. 25, No. 2 (Fall 2000), pp. 124–151© 2000 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology. 124 of Thomas Hobbes and Hans Morgenthau: Humans possess an innate animus dominandi, or drive to dominate. Both intellectual foundations are widely considered to be weak, however, because they rely either on a theological force or a metaphysical precept to explain state behavior. After the publication of Kenneth Waltz’s Theory of International Politics, which anchored realism on the more scientiªc foundation of structuralism and the anarchic international system , few scholars found classical realism (hereafter realism) relevant for their scholarship.4 Evolutionary theory provides a stronger foundation for realism because it is based on science, not on theology or metaphysics. I use the theory to explain two human traits: egoism and domination. I submit that the egoistic and dominating behavior of individuals, which is commonly described as “realist,” is a product of the evolutionary process.5 I focus on these two traits because they are critical components of any realist argument in explaining international politics.6 I also argue that evolutionary theory may be applied not only to realism, but also to some of the central issues in international politics including...