There is a slippage from “is” to “ought” in nearly all evolutionary theorizing, with arguments about natural behavior sliding into claims about the human good. It may be true—though any account of how precisely this occurred can at present be little more than speculation—that much of what we see as morality evolved in a process of natural selection. That does not mean that the results must be benign. Freud tried to develop a view of human nature in terms of which morality could be better understood; but he accepted that much that comes naturally to humans—such as sexual predation and other types of violence—had to be repressed in the interests of a civilized life. Civilization sometimes requires the repression of natural human traits, including some that may be sanctioned by prevailing moral codes. The moralities that have emerged by natural selection have no overriding authority.