Embracing a variant of group selection theory of evolution that allows for Richard Dawkins’ “selfish gene” hypothesis, Samuel Bowles of the Santa Fe Institute in New Mexico argues that people are altruistic because they are militaristic (“Blood and Treasure,” June 6, 2009). Comrades in arms become comrades in other things, as well. Which reminds me at once of Karl Marx’s Communist Manifesto (1848): “The history of all hitherto existing society is the history of class struggle.” Indeed, I remember Bowles most fondly from the early Seventies, when he taught and I studied economics at Harvard University. Together with Herbert Gintis, his comrade in arms at the time, he was a formidable teacher devoted to Marxian economics. I am glad to see that the old spirit is still with him, albeit in a new academic robe.