In our second patient we meet with fundamentally the same thing. She had created a decree which she must follow: the pillow must not touch the head of the bed; yet she does not know how it originated, what its meaning is, nor to what motive it owes the source of its power. It is immaterial whether she looks upon it with indifference or struggles against it, storms against it, determines to overcome it. She must nevertheless follow it and carry out its ordinance, though she asks herself, in vain, why. One must admit that these symptoms of compulsion neurosis offer the clearest evidence for a special sphere of psychological activity, cut off from the rest. What else could be back of these images and impulses, which appear from one knows not where, which have such great resistance to all the influences of an otherwise normal psychic life; which give the patient himself the impression that here are super-powerful guests from another world, immortals mixing in the affairs of mortals. Neurotic symptoms lead unmistakably to a conviction of the existence of an unconscious psychology, and for that very reason clinical psychiatry, which recognizes only a conscious psychology, has no explanation other than that they are present as indications of a particular kind of degeneration. To be sure, the compulsive images and impulses are not themselves unconscious--no more so than the carrying out of the compulsive-acts escapes conscious observation. They would not have been symptoms had they not penetrated through into consciousness. But their psychological antecedents as disclosed by the analysis, the associations into which we place them by our interpretations, are unconscious, at least until we have made them known to the patient during the course of the analysis. Consider now, in addition, that the facts established in our two cases are confirmed in all the symptoms of all neurotic diseases, that always and everywhere the meaning of the symptoms is unknown to the sufferer, that analysis shows without fail that these symptoms are derivatives of unconscious experiences which can, under various favorable conditions, become conscious. You will understand then that in psychoanalysis we cannot do without this unconscious psyche, and are accustomed to deal with it as with something tangible. Perhaps you will also be able to understand how those who know the unconscious only as an idea, who have never analyzed, never interpreted dreams, or never translated neurotic symptoms into meaning and purpose, are most ill-suited to pass an opinion on this subject. Let us express our point of view once more. Our ability to give meaning to neurotic symptoms by means of analytic interpretation is an irrefutable indication of the existence of unconscious psychological processes--or, if you prefer, an irrefutable proof of the necessity for their assumption.