Whoever among you takes the trouble to look into the matter will undoubtedly be deeply impressed by the wealth of evidential material. But he will also encounter difficulties. We have learned that the meaning of a symptom is found in its relation to the experience of the patient. The more highly individualized the symptom is, the sooner we may hope to establish these relations. Therefore the task resolves itself specifically into the discovery for every nonsensical idea and useless action of a past situation wherein the idea had been justified and the action purposeful. A perfect example for this kind of symptom is the compulsive act of our patient who ran to the table and rang for the maid. But there are symptoms of a very different nature which are by no means rare. They must be called typical symptoms of the disease, for they are approximately alike in all cases, in which the individual differences disappear or shrivel to such an extent that it is difficult to connect them with the specific experiences of the patient and to relate them to the particular situations of his past. Let us again direct our attention to the compulsion neurosis. The sleep ritual of our second patient is already quite typical, but bears enough individual features to render possible what may be called an _historic_ interpretation. But all compulsive patients tend to repeat, to isolate their actions from others and to subject them to a rhythmic sequence. Most of them wash too much. Agoraphobia (topophobia, fear of spaces), a malady which is no longer grouped with the compulsion neurosis, but is now called anxiety hysteria, invariably shows the same pathological picture; it repeats with exhausting monotony the same feature, the patient's fear of closed spaces, of large open squares, of long stretched streets and parkways, and their feeling of safety when acquaintances accompany them, when a carriage drives after them, etc. On this identical groundwork, however, the individual differences between the patients are superimposed--moods one might almost call them, which are sharply contrasted in the various cases. The one fears only narrow streets, the other only wide ones, the one can go out walking only when there are few people abroad, the other when there are many. Hysteria also, aside from its wealth of individual features, has a superfluity of common typical symptoms that appear to resist any facile historical methods of tracing them. But do not let us forget that it is by these typical symptoms that we get our bearings in reaching a diagnosis. When, in one case of hysteria we have finally traced back a typical symptom to an experience or a series of similar experiences, for instance followed back an hysterical vomiting to its origin in a succession of disgust impressions, another case of vomiting will confuse us by revealing an entirely different chain of experiences, seemingly just as effective. It