SELF: A Study in Ethics and Endocrinology considers the psycho-physical mechanisms and reactions in human nature and destiny. This book is composed of seven chapters and begins with a description of the complexity of human body and mind, specifically their physical basis and nature of functioning. These topics are followed by a presentation on the issues of homosexuality and hermaphrodism in human, as well as the role of endocrine system in these issues. The discussion then shifts to the psychiatric and psychological aspects of diverse human personality. A chapter examines the psychological distinction between male and female mind functioning. The last chapter focuses on the central problem of human ethics, the so-called ''free will''. This book will prove useful to psychologists, psychiatrists, and research workers who are interested in human nature.