T H I S book is not intended to be a history of psycho-analytical theory. In any complete form that would be a far larger under taking. Many important aspects of theory here omitted would have called for inclusion, particularly in the case of Freud and Melanie Klein. I have attempted something different, something that I believe needs to be done at about this time, something that arises as a problem out of the very nature of science as hitherto under stood, as soon as it comes to be applied to human beings. This involves making a historical survey, and I have sought to let the important writers speak for themselves. The justification for fairly frequent quotations and some lengthy ones must be found in this deliberate purpose. But such a survey would be mere mechanical hackwork, more or 1685 complete recording, unless the writer felt he could trace the emergence of deeper understanding along certain definite lines. The close study of psycho-analysis over many years, against the background of philosophical, religious, literary and social studies, has bred in me the conviction that here at last, and here alone, scientific enquiry has come face to face with the intimate and fully 'personal' life of man. This constitutes as big a test for science as for man. Science has to discover whether and how it can deal with the 'person', the 'unique individual', we will dare to say the 'spiritual self' with all the motives, values, hopes, fears and pur poses that constitute the real life of man, and make a purely 'organic' approach to man inadequate. On the other hand, man has to face the most penetrating searchlight focussed upon his essential nature, and must find out how to adjust to the stripping off of his psychic defences and self-deceptions, built up to hide failures in development towards maturity, while the struggle to cope with living in spite of immaturity is carried on.