Instinct and the Unconscious *Instinct and the Unconscious. By W. H. R. Rivers, M.D., D.Sc., LL.D., F.R.S. (Cambridge: University Press, 15s. net.)

jCIGMUND FREUD promulgated his epochmaking hypothesis of the unconscious mind just in time for the war to enable the truth of his theories to be tested on a large scale. And it was one of the few happy results of the war that it tempted from their academic seclusion men, such as Dr. Rivers, who, although members of the medical profession, had devoted themselves mainly to scientific investigations. Their intellects trained in the due weighing of evidence enabled them to judge controversial questions more fairly than others, perhaps, might have done. And of the work done by them this volume is a notable example. In his sub-title, Dr. Rivers describes his book as