The phrase "human nature" is multiply ambiguous. Some early modern thinkers such as Thomas Hobbes, John Locke, and Jean-Jacques Rousseau tended to mean by it the supposed nature of human beings before the advent of organized human society. But there is every reason to believe that human beings have always been highly social creatures, and that the idea of individuals coming together to form society is a myth.

Another ambiguity, exemplified in the opposition between Mencius and Hsun-tzu in the ancient Confucian tradition in China, and between differing traditions within Christianity, is over whether human nature is basically good and in need only of appropriate sustenance and education, or whether we are inherently evil and stand in need of discipline or radical transformation.

A further difference is between a conception of human nature as what is in each individual at birth (or, given modern understanding of...