T. H. Huxley (1825-1895) was not only an active protagonist in the religious and scientific upheaval that followed the publication of Darwin's theory of evolution but also a harbinger of the sociobiological debates about the implications of evolution that are now going on. His seminal lecture Evolution and Ethics, reprinted here with its introductory Prolegomena, argues that the human psyche is at war with itself, that humans are alienated in a cosmos that has no special reference to their needs, and that moral societies are of necessity in conflict with the natural conditions of their...