Initially, evolutionists struggled to explain altruistic behavior. Mathematical modeling in the 1930s convinced many that the problem goes away if altruism increased the probability that the altruist’s genes were favored in the next generation, even if the altruist perished. Thus the famous quip, “I’ll give my life for two brothers or eight first cousins”. Military self-sacrifice runs through history and across cultures. It is has been regarded as a problem because sacrifice for near kinsmen is negligible, mostly to the benefit of utterly unrelated comrades. Homer’s Iliad paints pictures of self-sacrificial courage on behalf of nonkin. It also formulates Agamemnon’s Rule on the genocide of the defeated. Simple mathematical modeling shows how genes supporting military altruism and language could rapidly become entrenched in the population of Homo sapiens by wars among Upper Paleolithic societies averaging no more than 150 souls. Human brain anatomy shows evidence of extreme selective pressure favoring size and complexity. Biologically, world peace has already been achieved. During the Neolithic Era, large societies emerged. No cheers here for war; on the contrary. No biology stands in the way of ending human war.
Jonathan Shay is a clinical psychiatrist whose treatment of combat trauma suffered by Vietnam veterans combined with his interpretations of the ancient accounts of battle described in Homer’s Iliad and Odyssey has contributed to the understanding of warfare’s effects on individuals. He received a B.A. (1963) from Harvard University and a M.D. (1971) and Ph.D. (1972) from the University of Pennsylvania. Since 1987, he has been a staff psychiatrist at the Department of Veteran Affairs Outpatient Clinic in Boston, Massachusetts. In 2001, Shay served as Visiting Scholar-at-Large at the U.S. Naval War College. From 2004 to 2005, he was Chair of Ethics, Leadership, and Personnel Policy in the Office of the U.S. Army Deputy Chief of Staff for Personnel. Shay received a MacArthur Fellowship in 2007, and from 2008 to 2009 he was the General Omar Bradley Chair of Strategic Leadership at the United States Army War College. Selected publications include Action Theory and Ego Psychology: A Model of the Personality (1963), Achilles in Vietnam: Combat Trauma and the Undoing of Character (1995), and Odysseus in America: Combat Trauma and the Trials of Homecoming (2002).