The author of 'On Killing,' Grossman is one of the few American psychologists who specialize in 'killology,' the physical and mental processes of killing.

developmental psychology there is a general understanding that an individual must master the twin areas of sexuality and aggression (Freud's Eros and Thanatos) in order to have truly achieved adulthood. In the same way, the maturation of the human race necessitates our collective mastery of these two areas. In recent years we have made significant progress in the field of sexology, and this book is dedicated to the creation and exploration of the equivalent field of "killology."