I know that for some time you have been longing to interrupt me with cries of: “Enough of these monstrosities! The motions of the bowels a source of pleasurable sexual satisfaction exploited even by infants! Fæces a substance of great value and the anus a kind of genital organ! We do not believe it; but we understand why children’s physicians and educationists have emphatically rejected psycho-analysis and its conclusions!” Not at all; you have merely forgotten for the moment that I have been endeavouring to show you the connection between the actual facts of infantile sexual life and the actual facts of the sexual perversions. Why should you not know that in many adults, both homosexual and heterosexual, the anus actually takes over the part played by the vagina in sexual intercourse? And that there are many persons who retain the pleasurable sensations accompanying evacuations of the bowels throughout life and describe them as far from insignificant? You may hear from children themselves, when they are a little older and able to talk about these things, what an interest they take in the act of defæcation and what pleasure they find in watching others in the act. Of course if you have previously systematically intimidated these children they will understand very well that they are not to speak of such things. And for all else that you refuse to believe I refer you to the evidence brought out in analysis and to the direct observation of children and I tell you that it will require the exercise of considerable ingenuity to avoid seeing all this or to see it in a different light. Nor am I at all averse from your thinking the relationship between childish sexual activities and the sexual perversions positively striking. It is a matter of course that there should be this relationship; for if a child has a sexual life at all it must be of a perverted order, since apart from a few obscure indications he is lacking in all that transforms sexuality into the reproductive function. Moreover, it is a characteristic common to all the perversions that in them reproduction as an aim is put aside. This is actually the criterion by which we judge whether a sexual activity is perverse—if it departs from reproduction in its aims and pursues the attainment of gratification independently. You will understand therefore that the gulf and turning-point in the development of the sexual life lies at the point of its subordination to the purposes of reproduction. Everything that occurs before this conversion takes place, and everything which refuses to conform to it and serves the pursuit of gratification alone, is called by the unhonoured title of “perversion” and as such is despised.