Not a few serious-minded students, [...], have been discouraged from attempting a study of Freud’s dream psychology. The book in which he originally offered to the world his interpretation of dreams was as circumstantial as a legal record to be pondered over by scientists at their leisure, not to be assimilated in a few hours by the average alert reader. In those days, Freud could not leave out any detail likely to make his extremely novel thesis evidentially acceptable to those willing to sift data. – Freud himself, however, realized the magnitude of the task which the reading of his magnum opus imposed upon those who have not been prepared for it by long psychological and scientific training and he abstracted from that gigantic work the parts which constitute the essential of his discoveries.