Here is the gap which psychoanalysis aims to fill. It prepares to give psychiatry the omitted psychological foundation, it hopes to reveal the common basis from which, as a starting point, constant correlation of bodily and psychic disturbances becomes comprehensible. To this end, it must divorce itself from every anatomical, chemical or physiological supposition which is alien to it. It must work throughout with purely psychological therapeutic concepts, and just for that reason I fear that it will at first seem strange to you. I will not make you, your previous training, or your mental bias share the guilt of the next difficulty. With two of its assertions, psychoanalysis offends the whole world and draws aversion upon itself. One of these assertions offends an intellectual prejudice, the other an aesthetic-moral one. Let us not think too lightly of these prejudices; they are powerful things, remnants of useful, even necessary, developments of mankind. They are retained through powerful affects, and the battle against them is a hard one. The first of these displeasing assertions of psychoanalysis is this, that the psychic processes are in themselves unconscious, and that those which are conscious are merely isolated acts and parts of the total psychic life. Recollect that we are, on the contrary, accustomed to identify the psychic with the conscious. Consciousness actually means for us the distinguishing characteristic of the psychic life, and psychology is the science of the content of consciousness. Indeed, so obvious does this identification seem to us that we consider its slightest contradiction obvious nonsense, and yet psychoanalysis cannot avoid raising this contradiction; it cannot accept the identity of the conscious with the psychic. Its definition of the psychic affirms that they are processes of the nature of feeling, thinking, willing; and it must assert that there is such a thing as unconscious thinking and unconscious willing. But with this assertion psychoanalysis has alienated, to start with, the sympathy of all friends of sober science, and has laid itself open to the suspicion of being a fantastic mystery study which would build in darkness and fish in murky waters. You, however, ladies and gentlemen, naturally cannot as yet understand what justification I have for stigmatizing as a prejudice so abstract a phrase as this one, that "the psychic is consciousness." You cannot know what evaluation can have led to the denial of the unconscious, if such a thing really exists, and what advantage may have resulted from this denial. It sounds like a mere argument over words whether one shall say that the psychic coincides with the conscious or whether one shall extend it beyond that, and yet I can assure you that by the acceptance of unconscious processes you have paved the way for a decisively new orientation in the world and in science.