That the emotions of sex should play an enormous part in the processes of analysis is to be expected; for the sex emotions are among the deepest, if not the deepest, of our nature, and colour every experience. From their proximate beginning in infancy—and Freud’s theory here is of immense significance—to their multiform derivatives in adult life, the sex emotions exercise an influence on every phase of development, and, in one form or another, are themselves a normal index of the stages of development. It is therefore reasonable to expect that they should play a great part in the formation of obsessions, of fixed ideas, of perversions, of repressed complexes. In every civilisation, as Freud indicates, the sex emotions are the most difficult to control, and have demanded the greatest amount of restraint. Restraints lead to repressions, repressions lead to dissociations, dissociations lead to irregularities of action. When, therefore, as in dreams, the restraints of the social day are withdrawn, naturally the repressed ideas tend to emerge once more. How much these ideas account for in the hysterias, how much “the shocks of despised love” affect even the normal life, needs no emphasis, but Freud pushes his analysis farther, and tracks the sex emotions, like many other fundamental emotions, into a thousand by-paths of ordinary experience. But it would be foolishness to say that sex emotions are everything in the ruins of the “Buried Temple.” Far from it. What is true of the sex emotions is true of all other emotions in their varying degrees, and often what looks like predominant sex emotions may turn out to be accidental rather than causative, a concomitant symptom rather than the initiatory centre of disturbance. But these points are all controversial. It is the object of Freud to put them to the test. If his general theory be true, the dream-world will more and more become the revealer of our deepest and oldest experience. It would be easy to fill many pages with illustrative items and relative criticisms, but that is not the purpose of an introduction. Here I am concerned simply to recommend this essay to the careful study of all those interested in the mental history of the individual, and in the blotting out from the mind of needless fears and anxieties. And no one need hesitate to enter on this study, whatever his metaphysical theories may be. Even the “unity of consciousness” will not suffer, for, through his unending efforts to link the experiences of the day with the whole experience of the individual life, Professor Freud, by the union of buried consciousness, restores to the mind a new unity of consciousness. Dr. Eder, whose studies in this field have been long and varied, does well to present to British readers this essay which serves as an introduction to the more elaborate studies of FREUD and his school, and I am glad to have the privilege of saying so. W. LESLIE MACKENZIE.