WITHIN the last ten years or so certain revolutionary ideas about the nature of the human mind and the influence of unconscious factors upon consciousness, have been rapidly gaining ground. This new psychology of the unconscious has attracted attention chiefly for two reasons: First, because it has been instrumental in helping to cure many cases of nervous disease, especially soldiers who seemed to be suffering permanent effects of "shell-shock," or overstrain. Medical men who have accepted, or at least have been greatly influenced by this new psychology, and who have made use of the now famous method of psycho-analysis, have been able to bring about cures in some cases in which the ordinary medical treatment had failed. These cures have been brought about, apparently, by the dragging up into consciousness of memories of experiences long buried in the unconscious.

Sometimes cures have followed so instantaneously upon the recovery of the memory as to appear almost miraculous. For example, one Canadian soldier entered hospital suffering from nervous debility. Examination revealed that he had forgotten a great deal about his past life, not only in the army, but before. He was not sure if he was married, but when he found in his pocket a photograph of a young woman he supposed it was his wife, and wanted to see her. Dr. William McDougal, under whose care he came, insisted upon continued attempts at recall, assisted by hypnotism. Eventually the lost memories came back with a rush, and almost at once there was a great increase of physical vigour. This was tested by an instrument for recording the strength of the hand-grip - the dynamometer. Up to the time of the recovery of memory, the patient had only been capable of a grip represented by 30 kilogrammes. Within an hour of his recovery of memory he squeezed the instrument until it recorded 90 kilogrammes.* The cure in this case was exceptionally rapid, but there are now a considerable number of cases of this type on record.

The second reason why this new psychology has attracted so much attention is because of its exceedingly novel interpretation of dreams, which are said to be due to the activities of the unconscious self. Their apparent absurdity is explicable, it is claimed, when the feelings and desires in the unconscious are brought to light, and when we understand the curious symbolism of the unconscious, which seems remarkably similar in the dreams of many different people and which appears further in some of the language of early myths.

* Article Summary, by Wm. McDougal, in Functional Nerve Disease, edited by H. Crichton Miller.

This new psychology is largely due to the work of Freud, a medical man who practised in Vienna, a fact which has probably militated against the reception of his theories in some countries.

Freud, being a doctor, was first interested in nervous diseases and their psychology, and his special concern with abnormal persons certainly colours all his work. The psychology which has grown from his work, however, professes also to throw much light upon our normal mental life, as well as upon dreams, which have been especially studied as a means of discovering the underlying causes of mental trouble and nervous disorders.

The Freudian views met at first with considerable scorn and derision, and in many quarters there is The Work of Freud.

still violent opposition to them. I confess that Freud's ideas first impressed me as fantastic. He indulges in unnecessarily sweeping generalisations. He finds the influence of sex in almost every abnormal mental process, though he covers this by a paradoxically wide interpretation of the term sex.

In spite, however, of the forbidding aspects of Freud's position, much of his work has now won the recognition and the admiration of many medical men and psychologists throughout the world. Several recent volumes entirely devoted to this new psychology originate in Harley Street. Recent meetings of the British Psychological Society have devoted considerable time to the discussion of the Freudian psychology. One of the most cautious and critical of English doctor-psychologists, who has had wide experience in military hospitals for nervous diseases, says that there is hardly a case among those with which he has had to deal, arising out of the war, which the Freudian theories did not help him to understand better, "not a day of clinical experience in which Freud's theories may not be of direct practical use in diagnosis and treatment." *

It is not, however, solely upon grave mental disease or on dreams that the new psychology throws light. Many impulsive and unreasonable actions, many prejudices and irrational fears and anxieties, many involuntary betrayals of inner motives, lapses of memory, slips of the tongue and other common aberrations of everyday life appear in a more comprehensible light on the hypothesis of the new psychology of the unconscious.

* W. H. R. Rivers, in "Freud's Psychology of the Unconscious," The Lancet, June 16. 1917.

It is partly as a result of the study of these in my own case, and in those of intimate friends, that I feel the value, for the study even of normal psychology, of much of the work of Freud and his successors. And this in spite of the fact that some of it, when reduced to fundamentals, is not as revolutionary as it may at first appear. For, as I hope to show later, we can connect some of Freud's theories, after they are modified as criticism seems to demand, with fundamental laws of the mind already familiar to psychology.

For a proper appreciation of the new theory of dreams it is necessary to be familiar first with certain other aspects of our subject. We shall, therefore, begin with a brief study of mental conflict, of the repression of impulses and emotions, and of the way in which such repressions affect waking life. We shall consider, at the same time, the evidence afforded by examples of the cures of mental disorders through psycho-analysis. Later, we shall turn to the study of the dream as a means of the release of such repressions and of the use of dreams in the discovery of unconscious influences at work in the mind. Finally, we shall consider the effect of unconscious influences in the everyday life of normal individuals.