Psychological - or more strictly speaking, psychoanalytic -investigation shows that the deepest essence of human nature, which are similar in all men and which aim at the satisfaction of certain needs... [are] self-preservation, aggression, need for love, and the impulse to attain pleasure and avoid pain...

These impulses in themselves are neither good nor bad. We classify them and their expressions in that way, according to their relation to the needs and demands of the human community. Civilized society, which demands good conduct and does not trouble itself about the instinctual basis of this conduct, has thus won over to obedience a great many people who are not in this, following their own natures.

Encouraged by this success society has allowed itself to be misled into tightening the moral standard to the greatest possible degree, and thus it had forced its members into a yet greater estrangement from their instinctual dispositions…They [the members of a society] are constantly subject to an unceasing suppression of instinct, and the resulting tension betrays itself in the most remarkable phenomena of reaction and compensation. In the domain of sexuality, where such suppression is most difficult to carry out, the result is seen in the reactive phenomena of neurotic disorders.

From "Thoughts for the Times on War and Death" 1925

It may be difficult, for many of us to abandon the belief that there is an instinct toward perfection at work in human beings, which has brought them to their present high level of intellectual achievement and ethical sublimation and which may be expected to watch over their development into supermen. I have no faith, however, in the existence of any such internal instinct and I cannot see how this benevolent illusion is to be preserved.

The present development of human beings requires, as it seems to me, no different explanation from that of animals. What appears in minority of human individuals as an untiring compulsion toward further perfection can easily be understood as a result of the instinctual repression upon which is based all that is most precious in human civilization

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From "Beyond the Pleasure Principle" 1920

I took as my starting point a saying of the poet-philosopher Schiller that "hunger and love are what move the world." Hunger could be taken to represent the instincts which aim at preserving the individual; while love strives after objects, and its chief function, favored in every way by nature, is the preservation of the species...

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... The natural instinct of aggressiveness in man, the hostility of each one against all and of all against each one, opposes this programme of civilization...

Men are not gentle creatures who want to be loved, and who at the most can defend themselves if they are attacked; they are, on the contrary, creatures among whose instinctual endowments is to be reckoned a powerful share of aggressiveness. As a result, their neighbor is for them not only a potential helper or sexual object, but also someone who tempts them to satisfy their aggressiveness on him, to exploit his capacity for work without compensation, to use him sexually without his consent, to seize his possessions, to humiliate him, to cause him pain, to torture and to kill him. Homo homini lupus. (Man is a wolf to man.)

Who, in the face of all his experience of life and of history, will have the courage to dispute this assertion? As a rule, this cruel aggressiveness waits for some provocation or puts itself at the service of some other purpose, whose goal might also have been reached by milder measures. In circumstances that are favorable to it, when the mental counterforce which ordinarily inhibit it are out of action, it also manifests itself spontaneously and reveals man as a savage beast to whom consideration toward his own kind is something alien.

Anyone who calls to mind the atrocities committed during the racial migrations of the invasions of the Huns, or by the people known as the Mongols under Genghis Khan and Tamerlane, or at the capture of Jerusalem by pious Crusaders, or even, indeed, the horrors of the recent World War - anyone who calls these things to mind will have to bow humbly before the truth of this view.

From "Civilization and its Discontents" 1927

The decisive question is whether and to what extent it is possible to lessen the burden of the instinctual sacrifices imposed on men, to reconcile men to those that must necessarily remain and to provide a compensation for them. It is just as impossible to do without control of the mass by a minority as it is to dispense with coercion in the work of civilization. For masses are lazy and unintelligent; they have no love for instinctual renunciation, and they are not to be convinced by argument of its inevitability; and the individuals composing them support one another in giving free rein to their indiscipline.

It is only through the influence of individuals who can set an example and whom the masses recognize as their leaders that they can be induced to perform the work and undergo the renunciations on which the existence of civilization depends. All is well if these leaders are persons who possess superior insight into the necessities of life and who have risen to the height of mastering their own instinctual wishes. But there is a danger that in order not to lose their influence they may give way to the mass more than it gives way to them, and it therefore seems necessary that they shall be independent of the mass by having means to power at their disposal.

To put it briefly, there are two widespread human characteristics which are responsible for the fact that the regulations of civilization can only be maintained by a certain degree of coercion -namely, that men are not spontaneously fond of work and that arguments are of no avail against their passions. Since men are so little accessible to reasonable arguments and are so entirely governed by their instinctual wishes, why should one set out to deprive them of an instinctual satisfaction and replace it by reasonable arguments? It is true that men are like this; but have you asked yourself whether they must be like this, whether their innermost nature necessitates it?

We may insist as often as we like that man's intellect is powerless in comparison with his instinctual life, and we may be right in this. Nevertheless, there is something peculiar about this weakness. The voice of the intellect is a soft one, but it does not rest until it has gained a hearing. Finally, after a countless succession of rebuffs, it succeeds. This is one of the few points on which one may be optimistic about the future of mankind, but it is in itself a point of no small importance.

From "The Future of an Illusion" 1927

The fateful question for the human species seems to me to be whether and to what extent their cultural development will succeed in mastering the disturbance of their communal life by the human instinct of aggression and self-destruction. It may be that in this respect, precisely the present time deserves a special interest.

Men have gained control over the forces of nature to such an extent that with their help they would have no difficulty in exterminating one another to the last man. They know this, and hence comes a large part of their current unrest, their unhappiness and their mood of anxiety. And now it is to be expected that the other of the two "Heavenly Powers", eternal Eros, will make an effort to assert himself in the struggle with his equally immortal adversary. But who can foresee with what success and with what result?