Denis Diderot

The infant runs toward it with its eyes closed, the adult is stationary, the old man approaches it with his back turned.

We are all instruments endowed with feeling and memory. Our senses are so many strings that are struck by surrounding objects and that also frequently strike themselves.

Superstition is more injurious to God than atheism.

It has been said that love robs those who have it of their wit, and gives it to those who have none.

If your little savage were left to himself and be allowed to retain all his ignorance, he would in time join the infant’s reasoning to the grown man’s passion, he would strangle his father and sleep with his mother.

People praise virtue, but they hate it, they run away from it. It freezes you to death, and in this world you've got to keep your feet warm.

Impenetrable in their dissimulation, cruel in their vengeance, tenacious in their purposes, unscrupulous as to their methods, animated by profound and hidden hatred for the tyranny of man — it is as though there exists among them an ever-present conspiracy toward domination, a sort of alliance like that subsisting among the priests of every country.

Go further, and require each of them to make a contribution: you will see how many things are still missing, and you will be obliged to get the assistance of a large number of men who belong to different classes, priceless men, but to whom the gates of the academies are nonetheless closed because of their social station. All the members of these learned societies are more than is needed for a single object of human science; all the societies together are not sufficient for a science of man in general.

As to all the outward signs that awaken within us feelings of sympathy and compassion, the blind are only affected by crying; I suspect them in general of lacking humanity. What difference is there for a blind man, between a man who is urinating, and man who, without crying out, is bleeding? And we ourselves, do we not cease to commiserate, when the distance or the smallness of the objects in question produce the same effect on us as the lack of sight produces in the blind man? All our virtues depend on the faculty of the senses, and on the degree to which external things affect us. Thus I do not doubt that, except for the fear of punishment, many people would not feel any remorse for killing a man from a distance at which he appeared no larger than a swallow. No more, at any rate, than they would for slaughtering a cow up close. If we feel compassion for a horse that suffers, but if we squash an ant without any scruple, isn’t the same principle at work?

I have often seen an actor laugh off the stage, but I don’t remember ever having seen one weep.

When one compares the talents one has with those of a Leibniz, one is tempted to throw away one's books and go die quietly in the dark of some forgotten corner.

To say that man is a compound of strength and weakness, light and darkness, smallness and greatness, is not to indict him, it is to define him.

Of course it would not do for the church to allow a man to die in peace who had added to the intellectual wealth of the world. The moment Diderot was dead, Catholic priests began painting and recounting the horrors of his expiring moments. They described him as overcome with remorse, as insane with fear; and these falsehoods have been repeated by the Protestant world, and will probably be repeated by thousands of ministers after we are dead.
The truth is, he had passed his threescore years and ten. He had lived for seventy-one years. He had eaten his supper. He had been conversing with his wife. He was reclining in his easy chair. His mind was at perfect rest. He had entered, without knowing it, the twilight of his last day. Above the horizon was the evening star, telling of sleep. The room grew still and the stillness was lulled by the murmur of the street. There were a few moments of perfect peace. The wife said, "He is asleep." She enjoyed his repose, and breathed softly that he might not be disturbed. The moments wore on, and still he slept. Lovingly, softly, at last she touched him. Yes, he was asleep. He had become a part of the eternal silence.

There is no moral precept that does not have something inconvenient about it.

There is no kind of harassment that a man may not inflict on a woman with impunity in civilized societies.

Bad company is as instructive as licentiousness. One makes up for the loss of one’s innocence with the loss of one’s prejudices.

Poetry must have something in it that is barbaric, vast and wild.

Justice is the first virtue of those who command, and stops the complaints of those who obey.

To attempt the destruction of our passions is the height of folly. What a noble aim is that of the zealot who tortures himself like a madman in order to desire nothing, love nothing, feel nothing, and who, if he succeeded, would end up a complete monster!

Pithy sentences are like sharp nails which force truth upon our memory.