It would be more difficult to explain concisely how it came about that psychoanalysis made a further distinction in the unconscious, and separated it into a _preconscious_ and an unconscious proper. It will be sufficient to say that it appeared a legitimate course to supplement the theories which were a direct expression of experience by hypotheses which were designed to facilitate the handling of the material and related to matters which could not be a subject of immediate observation. The very same procedure is adopted by the older sciences. The sub-division of the unconscious is part of an attempt to picture the apparatus of the mind as being built up of a number of _instances_ or systems, whose inter-relations may be expressed in spatial terms, without reference, of course, to the actual anatomy of the brain. (I have described this as the _topographical method of approach_.) Such ideas as these are part of a speculative superstructure of psychoanalysis, any portion of which can be abandoned or changed without loss or regret the moment its inadequacy has been proved. But there is still plenty to be described that lies closer to actual experience. I have already mentioned that my investigation of the precipitating and underlying causes of the neuroses led me more and more frequently to conflicts between the subject’s sexual impulses and his resistances to sexuality. In my search for the pathogenic situations in which the repressions of sexuality had set in and in which the symptoms, as substitutes for what was repressed, had their origin, I was carried further and further back into the patient’s life and ended by reaching the first years of his childhood. What poets and students of human nature had always asserted turned out to be true: the impressions of that remote period of life, though they were for the most part buried in amnesia, left ineradicable traces upon the individual’s growth and in particular laid the foundations of any nervous disorder that was to follow. But since these experiences of childhood were always concerned with sexual excitations and the reaction against them, I found myself faced by the fact of infantile sexuality—once again a novelty and a contradiction of one of the strongest of human prejudices. Childhood was looked upon as “innocent” and free from the lusts of sex, and the fight with the demon of “sensuality” was not thought to begin until the troubled age of puberty. Such occasional sexual activities as it had been impossible to overlook in children were put down as signs of degeneracy and premature depravity or as a curious freak of nature. Few of the findings of psychoanalysis have met with such universal contradiction or have aroused such an outburst of indignation as the assertion that the sexual function starts at the beginning of life and reveals its presence by important signs even in childhood. And yet no other finding of analysis can be demonstrated so easily and so completely.