From Civilization and Its Discontents (1930)
... The assumption of the existence of an instinct of death or destruction has met with resistance even in analytic circles; I am aware that there is a frequent inclination rather to ascribe whatever is dangerous and hostile in love to an original bipolarity in its own nature. To begin with it was only tentatively that I put forward the views I have developed here, but in the course of time they have gained such a hold upon me that I can no longer think in any other way. To my mind, they are far more serviceable from a theoretical standpoint than any other possible ones; they provide that simplification, without either ignoring or doing violence to the facts, for which we strive in scientific work. I know that in sadism and masochism we have always seen before us manifestations of the destructive instinct (directed outwards and inwards), strongly alloyed with erotism; but I can no longer understand how we can have overlooked the ubiquity of non-erotic aggressivity and destructiveness and can have failed to give it its due place in our interpretation of life. ("The desire for destruction when it is directed inwards mostly eludes our perception, of course, unless it is tinged with erotism.) I remember my own defensive attitude when the idea of an instinct of destruction first emerged in psycho-analytic literature, and how long it took before I became receptive to it. That others should have shown, and still show, the same attitude of rejection surprises me less. For 'little children do not like it' when there is talk of the inborn human inclination to 'badness', to aggressiveness and destructiveness, and so to cruelty as well. God has made them in the image of His own perfection; nobody wants to be reminded how hard it is to reconcile the undeniable existence of evil — despite the protestations of Christian Science — with His all-powerfulness or His all-goodness. The Devil would be the best way out as an excuse for God; in that way he would be playing the same part as an agent of economic discharge as the Jew does in the world of the Aryan ideal. But even so, one can hold God responsible for the existence of the Devil just as well as for the existence of the wickedness which the Devil embodies. In view of these difficulties, each of us will be well advised, on some suitable occasion, to make a low bow to the deeply moral nature of mankind; it will help us to be generally popular and much will be forgiven us for it. ...
Used with permission. All rights reserved. Translation by James Strachey.