Completely revised to take into account the scholarship since its first publication in 1974 and expanded to include Eastern thinkers, Ten Theories of Human Nature has added chapters on Hinduism and Confucianism as well as a new chapter on Kant. The text is intended to compress into a small space the essence of such thinkers as Karl Marx, Sigmund Freud, Jean Paul Sartre, B.F. Skinner, and Konrad Lorenz. The authors juxtapose the ideas of these and other thinkers in order to help the reader understand how humanity has struggled to comprehend its nature. It is demonstrated, for example, how Skinner's theories - which assert the primacy of learned behavior - are undercut by Lorenz's studies of animals, which suggest that complex behavior can occur prior to learning. To bring these comparisons into sharp relief, the book examines each theorist on four points: the nature of the universe; the nature of humanity; the ills of the world; and the proposed cure for these ills.