THE FIRST EDITION of this book was based primarily on experience with adult male psychopaths hospitalized in a closed institution. Though a great many other psychopaths had come to my attention, most of the patients who were observed over years and from whom emerged the basic concepts presented in 1941 were from this group. During the next decade a much more diverse group became available. Female patients, adolescents, people who had never been admitted to a psychiatric hospital, all in large (...) numbers, became available for study and afforded an opportunity to observe the disorder in a very wide range of variety and of degree. This additional clinical experience, helpful comment in the reviews of the first edition, enlightening discussion with colleagues, and an improved acquaintance with the literature all contributed to modify concepts formulated approximately ten years earlier. In attempting to revise the book for the second edition (1950), I found it was impossible to do justice to the subject by minor additions, deletions, and modifications. It was necessary to write a new and much larger book. (shrink)