NEVER before in any of my previous writings have I had the feeling so strongly as I have now that what I am describing is common knowledge, that I am requisitioning paper and ink, and in due course the labour of compositors and printers, in order to expound things that in themselves are obvious. For this reason, if it should appear that the recognition of a special independent instinct of aggression would entail a modification of the psycho-an*lytical theory of instincts, I should be glad enough to seize upon the idea. We shall see that this is not so, that it is merely a matter of coming to closer quarters with a conclusion to which we long ago committed ourselves and following it out to its logical consequences. The whole of an*lytic theory has evolved gradually enough, but the theory of instincts has groped its way forward under greater difficulties than any other part of it. And yet a theory of instincts was so indispensable for the rest that something had to be adopted in place of it. In my utter perplexity at the beginning, I took as my starting-point the poet-philosopher Schiller''s aphorism that hunger and love make the world go round. Hunger would serve to represent those instincts which aim at preservation of the individual; love seeks for objects: its chief function, which is favoured in every way by nature, is preservation of the species. Thus first arose the contrast between ego instincts and object instincts. For the energy of the latter instincts, and exclusively for them, I introduced the term libido; an antithesis was thus formed between the ego instincts and the libidinal instincts directed towards objects, i. e., love in its widest sense. One of these object instincts, the sadistic, certainly stood out from the rest in that its aim was so very unloving; moreover, it clearly allied itself in many of its aspects with the ego instincts, and its close kinship with instincts of mastery without any libidinal purpose could not be concealed, but these ambiguities could be overcome; in spite of them, sadism plainly belonged to s**ual life——the game of cruelty could take the place of the game of love. Neurosis appeared as the outcome of a struggle between the interests of self-preservation and the claims of libido, a struggle in which the ego was victorious, but at the price of great suffering and renunciations. Every an*lyst will admit that none of this even now reads like a statement long since recognized as erroneous. All the same, modifications had to be made as our researches advanced from the repressed to the repressing, from the object instincts to the ego. A cardinal point in this advance was the introduction of the concept of narcissism, i. e.. the idea that libido cathects the ego itself, that its first dwelling-place was in the ego, and that the latter remains to some extent its permanent headquarters. This narcissistic libido turns in the direction of objects, thus becoming object-libido, and can transform itself back into narcissistic libido. The concept of narcissism made it possible to consider the traumaticneuroses, as well as many diseases bordering on the psychoses, and also the latter themselves, from the psycho-an*lytic angle. It was not necessary to abandon the view that the transference-neuroses are attempts on the part of the ego to guard itself against s**uality, but the concept of the libido was jeopardized. Since the ego-instincts were found to be libidinal as well, it seemed for a time inevitable that libido should become synonymous with instinctual energy in general, as C. G. Jung had previously advocated. Yet there still remained in me a kind of conviction, for which as yet there were no grounds, that the instincts could not all be of the same nature. I made the next step in Beyond the Pleasure Principle (1920), when the repetition-compulsion and the conservative character of instinctual life first struck me. On the basis of speculations concerning the origin of life and of biological parallels, I drew the conclusion that, beside the instinct preserving the organic substance and binding it into ever larger units, 23 there must exist another in antithesis to this, which would seek to dissolve these units and reinstate their antecedent inorganic state. That is to say, a d**h instinct as well as Eros; the phenomena of life would then be explicable from the interplay of the two and their counteracting effects on each other. It was not easy, however, to demonstrate the working of this hypothetical d**h instinct. The manifestations of Eros were conspicuous and audible enough; one might a**ume that the d**h instinct worked silently within the organism towards its disintegration, but that, of course, was no proof. The idea that part of the instinct became directed towards the outer world and then showed itself as an instinct of aggression and destruction carried us a step further. The instinct would thus itself have been pressed into the service of Eros, in that the organism would be destroying something animate or inanimate outside itself instead of itself. Conversely, any cessation of this flow outwards must have the effect of intensifying the self-destruction which in any case would always be going on within. From this example one could then surmise that the two kinds of instincts seldom——perhaps never——appear in isolation, but always mingle with each other in different, very varying proportions, and so make themselves unrecognizable to us. Sadism, long since known to us as a component-instinct of s**uality, would represent a particularly strong admixture of the instinct of destruction into the love impulse; while its counterpart, masochism, would be an alliance between s**uality and the destruction at work within the self, in consequence of which the otherwise imperceptible destructive trend became directly evident and palpable. The a**umption of the existence of a d**h instinct or a destruction instinct has roused opposition even in an*lytical circles; I know that there is a great tendency to ascribe all that is dangerous and hostile in love rather to a fundamental bipolarity in its own nature. The conceptions I have summarized here I first put forward only tentatively, but in the course of time they have won such a hold over me that I can no longer think in any other way. To my mind they are theoretically far more fruitful than any others it is possible to employ; they provide us with that simplification, without either ignoring or doing violence to the facts, which is what we strive after in scientific work. I know that we have always had before our eyes manifestations of the destruction instinct fused with erotism, directed outwards and inwards in sadism and masochism; but I can no longer understand how we could have overlooked the universality of non-erotic aggression and destruction, and could have omitted to give it its due significance in our interpretation of life. (It is true that the destructive trend that is directed inwards, when it is not erotically tinged, usually eludes our perceptions. ) I can remember my own defensive attitude when the idea of an instinct of destruction first made its appearance in psycho-an*lytical literature and how long it took until I became accessible to it. That others should have shown the same resistance, and still show it, surprises me less. Those who love fairy-tales do not like it when people speak of the innate tendencies in mankind towards aggression, destruction, and. in addition, cruelty. For God has made them in his own image, with his own perfections; no one wants to be reminded how hard it is to reconcile the undeniable existence——in spite of all the protestations of Christian Science——of evil with His omnipotence and supreme goodness. The devil is, in fact, the best way out in acquittal of God; he can be used to play the same economic role of outlet as Jews in the world of Aryan ideals. But even so, one can just as well hold God responsible for the existence of the devil as for the evil he personifies. In view of these difficulties, it is expedient for every man to make humble obeisance on suitable occasions in honour of the high-minded nature of men; it will a**ist him to become universally beloved and much shall be forgiven unto him on account of it. 24 The name libido can again be used to denote the manifestations of the power of Eros in contradistinction to the energy of the d**h instinct. 25 We must confess that it is more difficult for us to detect the latter, and to a great extent we can merely conjecture its existence as a background to Eros, also that it eludes us wherever it is not betrayed by a fusion with Eros. In sadism, where it bends the erotic aim to its own will and yet at the same time gratifies the s**ual craving completely, we can obtain the clearest insight into its nature and its relation to Eros. But even where it shows itself without any s**ual purpose, even in the blindest frenzy of destructiveness, one cannot ignore the fact that satisfaction of it is accompanied by an extraordinarily intense narcissistic enjoyment, due to the fulfilment it brings to the ego of its oldest omnipotence-wishes. The instinct of destruction, when tempered and harnessed (as it were, inhibited in its aim) and directed towards objects, is compelled to provide the ego with satisfaction of its needs and with power over nature. Since the a**umption of its existence is based essentially on theoretical grounds, it must be confessed that it is not entirely proof against theoretical objections. But this is how things appear to us now in the present state of our knowledge; future research and reflection will undoubtedly bring further light which will decide the question. In all that follows, I take up the standpoint that the tendency to aggression is an innate, independent, instinctual disposition in man, and I come back now to the statement that it constitutes the most powerful obstacle to culture. At one point in the course of this discussion, the idea took possession of us that culture was a peculiar process pa**ing over human life and we are still under the influence of this idea We may add to this that the process proves to be in the service of Eros, which aims at binding together single human individuals, then families, then tribes, races, nations, into one great unity, that of humanity. Why this has to be done we do not know; it is simply the work of Eros. These ma**es of men must be bound to one another libidinally; necessity alone, the advantages of common work, would not hold them together. The natural instinct of aggressiveness in man, the hostility of each one against all and of all against each one. opposes this program of civilization. This instinct of aggression is the derivative and main representative of the d**h instinct we have found alongside of Eros, sharing his rule over the earth. And now, it seems to me, the meaning of the evolution of culture is no longer a riddle to us. It must present to us the struggle between Eros and d**h, between the instincts of life and the instincts of destruction, as it works itself out in the human species. This struggle is what all life essentially consists of and so the evolution of civilization may be simply described as the struggle of the human species for existence. 26 And it is this battle of the Titans that our nurses and governesses try to compose with their lullaby-song of Heaven! Footnotes: 23 The contradiction between the tireless tendency of Eros to spread ever further and the general conservative nature of the instincts here becomes very noticeable; it would serve as the starting-point of enquiries into further problems. 24 In Goethe''s Mephistopheles we have a quite exceptionally striking identification of the principle of evil with the instinct of destruction: All entities that be Deserve their end——nonentity. So all that you name sin, destruction—— Wickedness, briefly——proves to be The native element for me. As his adversary, the devil himself cites not what is holy and good, but the power in nature working towards the creation and renewal of life——that is, Eros. From air, from water, germs in thousands, As from the soil, break forth, break free, Dry, wet, warm, cold——a pullulation! Had I not laid on flame a reservation, Nothing were set apart for me. 25 Our present point of view can be roughly expressed in the statement that libido participates in every instinctual manifestation, but that not everything in that manifestation is libido. 26 And we may probably add more precisely that its form was necessarily determined after some definite event which still remains to be discovered.