Sigmund Freud

Mans most disagreeable habits and idiosyncrasies, his deceit, his cowardice, his lack of reverence, are engendered by his incomplete adjustment to a complicated civilisation. It is the result of the conflict between our instincts and our culture.

All that matters is love and work.

After all, we did not invent symbolism; it is a universal age-old activity of the human imagination.

Men have gained control over the forces of nature to such an extent that with their help they would have no difficulty 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.

No one who, like me, conjures up the most evil of those half-tamed demons that inhabit the human breast, and seeks to wrestle with them, can expect to come through the struggle unscathed.

Thinking is an experimental dealing with small quantities of energy, just as a general moves miniature figures over a map before setting his troops in action.

Religious doctrines … are all illusions, they do not admit of proof, and no one can be compelled to consider them as true or to believe in them.

Immorality, no less than morality, has at all times found support in religion.

When we attempt to imagine death, we perceive ourselves as spectators.

The primitive stages can always be re-established; the primitive mind is, in the fullest meaning of the word, imperishable.

Sexuality is the key to the problem of the psychoneuroses and of the neuroses in general. No one who disdains the key will ever be able to unlock the door.

In human beings pure masculinity or femininity is not to be found either in a psychological or biological sense.

Writers write for fame, wealth, power and the love of women.

Civilization is a process in the service of Eros, whose purpose is to combine single human individuals, and after that families, then races, peoples and nations, into one great unity, the unity of mankind. Why this has to happen, we do not know; the work of Eros is precisely this.

The impression forces itself upon one that men measure by false standards, that everyone seeks power, success, riches for himself, and admires others who attain them, while undervaluing the truly precious thing in life.

I consider it a good rule for letter-writing to leave unmentioned what the recipient already knows, and instead tell him something new.

The reproaches against science for not having yet solved the problems of the universe are exaggerated in an unjust and malicious manner; it has truly not had time enough yet for these great achievements. Science is very young--a human activity which developed late.

No, our science is no illusion. But an illusion it would be to suppose that what science cannot give us we can get elsewhere.

I've been a fortunate man in life, nothing has come easily.

Look into the depths of your own soul and learn first to know yourself, then you will understand why this illness was bound to come upon you and perhaps you will thenceforth avoid falling ill.

In the development of mankind as a whole, just as in individuals, love alone acts as the civilizing factor in the sense that it brings a change from egoism to altruism.