My friends have learned never to ask about my Marine experience. Although I spent a small fraction of my life wearing camouflage, that time occupies about 80 percent of my memories.
In 1943, the U.S. Marines attacked Japanese positions on Tarawa. Of the 5,000 Marines in the initial attack, 1,500 were killed or wounded. Many Marines had to wade more than half a mile through surf turned red with blood and filled with dead bodies.
In 1983, I entered boot camp to learn how Marines could act as they did at Tarawa and elsewhere. At 23, I was one of the oldest members of my platoon and the only college graduate. Jaded, I expected to avoid indoctrination as I dissected the tactics of my drill instructors. Yet on just the 22nd day of training, I cried in church over the deaths of a helicopter full of Marines flying near the Korean DMZ.
As we sang the Marine Corps hymn, I was stunned by the genuine sadness I felt for my fallen "brothers." How had three weeks of boot camp made me a Marine? Had I been a better student of psychology, I'd have known that human behavior is influenced by the situation to an unexpectedly large degree.
In his well-known study, for example, Stanley Milgram built a very specific environment where 65 percent of average people gave high-voltage shocks to a victim who cried and begged for the torture to stop. (Fortunately, the victim was just acting.) The summary of hundreds of related studies is that people are much more malleable than either they or others predict.
One of the most famous lines in sociobiology comes from The Selfish Gene, where Richard Dawkins writes, "Now they swarm in huge colonies, safe inside gigantic lumbering robots … they go by the name of genes, and we are their survival machines."
Critics use "lumbering robots" to suggest that modern Darwinists are genetic determinists. Nothing could be further from Dawkins' intention or from the truth. There is a genetic, universal humannature, but because the environment is so important, human behavior varies infinitely.
In Mean Genes, Jay Phelan and I joke about the dearth of self-help books titled "How to Build a Bigger Beer Gut, Ten Steps to Frivolous Spending, or Nurturing the Infidel Within." Our joke makes a serious point. If people simply seek pleasure and avoid pain, the outcome is unlikely to be pretty. Simply going with the flow often leads to obesity, bankruptcy, and unfulfilling relationships.
Genes build organisms to foster their goals and care nothing for happiness, justice, and peace. In the Australian social spider, for example, the power of genetic interests is clear. After giving birth to about a hundred hungry spiderlings, Mom's body literally liquefies into a pile of mushy flesh. The babies then completely consume the gooey mess and begin life with some real home cooking in their bellies. Genes are selfish, powerful, and pervasive. If they can build a dissolving, edible mom, what hope do we have?
Returning, as I often do, to my Marine memories, I recall a day in tank school at Fort Knox when a sergeant threw my entire bed out the third-floor window because a fold was the wrong size. As we went to sleep in the dark another night, my "friends" placed a bloody deer head on the tank fender that they knew I used as a pillow.
My most poignant memory, however, comes from collecting donations to buy Q-Tips to clean our rifles for a boot camp inspection. Money was tight as each recruit had only $90 for three months of shaving cream and other sundries. Accordingly, I was getting small donations of 10 cents or so until one recruit donated $5. I said that we didn't need so much. He replied, "Neither do I." An act of generosity that still tingles my spine.
When I think about the challenge you describe as "formulating a modern spiritual world view grounded in Darwinian self-understanding," I recall the generosity of my friend. His $5 was not a "random act of altruism," but rather was fostered by a very special environment.
Perhaps paradoxically, Marine culture is socialistic—all other things being equal, a Marine gets paid more if he or she is married and still more for each child. Socialism may not have worked in Russia, but socialism in combat units has proved to be effective.
Humans are not lumbering robots; we are acutely sensitive to the incentives. If, after writing The Moral Animal and Nonzero, your thoughts on how to build those incentives are hazy, mine are a formless mass. Although ignorant of the specifics, I remain optimistic for two reasons. First, humans are uniquely able to use rationality to build productive systems. Second, we have powerful instincts for cooperation and altruism that can be nurtured.