Twenty years is a long time in the life of a science. While the historical roots of psychology have not changed since the first edition of this book, some of the offshoots of the various theories and systems discussed have been crit- ically reexamined and have undergone far-reaching modifications. New and bold research has led to a broadening of perspectives, and recent devel- opments in several areas required a considerable amount of rewriting. I have been fortunate in the last fifteen years to have worked with about 2,000 psychologists and other behavioral scientists who contributed to several collected volumes I have edited. As the editor-in-chief of the In- ternational Encyclopedia of Psychiatry, Psychology, Psychoanalysis and Neurol- ogy, I have had the privilege of reading, scrutinizing, and editing the work of 1,500 experts in psychology and related disciplines. In addition, I have written several books and monographs and over one hundred scientific papers. Armed with all that experience, I have carefully examined the pages of the first edition. Chapter 8 required substantial rewriting and several new sections have been added to other chapters: "e;Current Soviet Psychol- ogy"e; (Chapter 2, Section 7); "e;New Ideas on Purposivism"e; (Chapter 5, Sec- tion 4); "e;Recent Developments in the Sociological School of Psychoanalysis"e; (Chapter 9, Section 4); and "e;Present Status of Gestalt Psychology"e; (Chapter 12, Section 4). Chapter 15 was omitted, and two new chapters were added: Chapter 14 ("e;Humanistic Psychology"e;) and Chapter 16 ("e;Selected Research Areas"e;).

Twenty years is a long time in the life of a science. While the historical roots of psychology have not changed since the first edition of this book, some of the offshoots of the various theories and systems discussed have been crit- ically reexamined and have undergone far-reaching modifications. New and bold research has led to a broadening of perspectives, and recent devel- opments in several areas required a considerable amount of rewriting. I have been fortunate in the last fifteen years to have worked with about 2,000 psychologists and other behavioral scientists who contributed to several collected volumes I have edited. As the editor-in-chief of the In- ternational Encyclopedia of Psychiatry, Psychology, Psychoanalysis and Neurol- ogy, I have had the privilege of reading, scrutinizing, and editing the work of 1,500 experts in psychology and related disciplines. In addition, I have written several books and monographs and over one hundred scientific papers. Armed with all that experience, I have carefully examined the pages of the first edition. Chapter 8 required substantial rewriting and several new sections have been added to other chapters: "e;Current Soviet Psychol- ogy"e; (Chapter 2, Section 7); "e;New Ideas on Purposivism"e; (Chapter 5, Sec- tion 4); "e;Recent Developments in the Sociological School of Psychoanalysis"e; (Chapter 9, Section 4); and "e;Present Status of Gestalt Psychology"e; (Chapter 12, Section 4). Chapter 15 was omitted, and two new chapters were added: Chapter 14 ("e;Humanistic Psychology"e;) and Chapter 16 ("e;Selected Research Areas"e;).