ABSTRACT
It is clear that the varying "degrees of liberty" in society, with their corresponding restrictions, lead to the development of extremely varied overt behaviour patterns. The psychoanalytical insight into the variety of possible vicissitudes of instinct requires to be supplemented by knowledge of the social conditions, if psychoanalysts are to trace the motives of behaviour in either the individual or the group. Without co-operation between the sociologist and the psychologist the actual behaviour is unpredictable. The son of a twentieth-century industrialist is hardly likely to succeed in business following the rules of conduct which a citizen of the fourteenth century would have recommended to his heir. It is also obvious that similar types of character have unequal chances of success in different historical periods. What the psycho-analytical theory of instincts really teaches is that instincts can be deflected far from their primary aims.
