Routledge is now re-issuing this prestigious series of 204 volumes originally published between 1910 and 1965. The titles include works by key figures such asC.G. Jung, Sigmund Freud, Jean Piaget, Otto Rank, James Hillman, Erich Fromm, Karen Horney and Susan Isaacs. Each volume is available on its own, as part of a themed mini-set, or as part of a specially-priced 204-volume set. A brochure listing each title in the "International Library of Psychology" series is available upon request.

First Published in 1999. This is Volume I of ten in the Physiological Psychology series. Written in 1930, this book is an attempt to define the nature of feeling, that which in ordinary language is called pleasure and pain, or in more technically psychological terms the affective side of the 'mental life.