It is, therefore, to these phenomena that I would now direct your attention. But you will object, with annoyance: "There are so many sublime riddles in the external world, just as there are in the narrower world of the psychic life, and so many wonders in the field of psychic disturbances which demand and deserve elucidation, that it really seems frivolous to waste labor and interest on such trifles. If you can explain to us how an individual with sound eyes and ears can, in broad daylight, see and hear things that do not exist, or why another individual suddenly believes himself persecuted by those whom up to that time he loved best, or defend, with the most ingenious arguments, delusions which must seem nonsense to any child, then we will be willing to consider psychoanalysis seriously. But if psychoanalysis can do nothing better than to occupy us with the question of why a speaker used the wrong word, or why a housekeeper mislaid her keys, or such trifles, then we know something better to do with our time and interest." My reply is: "Patience, ladies and gentlemen. I think your criticism is not on the right track. It is true that psychoanalysis cannot boast that it has never occupied itself with trifles. On the contrary, the objects of its observations are generally those simple occurrences which the other sciences have thrown aside as much too insignificant, the waste products of the phenomenal world. But are you not confounding, in your criticism, the sublimity of the problems with the conspicuousness of their manifestations? Are there not very important things which under certain circumstances, and at certain times, can betray themselves only by very faint signs? I could easily cite a great many instances of this kind. From what vague signs, for instance, do the young gentlemen of this audience conclude that they have won the favor of a lady? Do you await an explicit declaration, an ardent embrace, or does not a glance, scarcely perceptible to others, a fleeting gesture, the prolonging of a hand-shake by one second, suffice? And if you are a criminal lawyer, and engaged in the investigation of a murder, do you actually expect the murderer to leave his photograph and address on the scene of the crime, or would you, of necessity, content yourself with fainter and less certain traces of that individual? Therefore, let us not undervalue small signs; perhaps by means of them we will succeed in getting on the track of greater things. I agree with you that the larger problems of the world and of science have the first claim on our interest. But it is generally of little avail to form the definite resolution to devote oneself to the investigation of this or that problem. Often one does not know in which direction to take the next step. In scientific research it is more fruitful to attempt what happens to be before one at the moment and for whose investigation there is a discoverable method. If one does