Denis Diderot

The arbitrary rule of a just and enlightened prince is always bad. His virtues are the most dangerous and the surest form of seduction: they lull a people imperceptibly into the habit of loving, respecting, and serving his successor, whoever that successor may be, no matter how wicked or stupid.

This root [the potato], no matter how much you prepare it, is tasteless and floury. It cannot pass for an agreeable food, but it supplies a food sufficiently abundant and sufficiently healthy for men who ask only to sustain themselves. The potato is criticized with reason for being windy, but what matters windiness for the vigorous organisms of peasants and laborers?

Do you see this egg? With this you can topple every theological theory, every church or temple in the world.

There are three principal means of acquiring knowledge... observation of nature, reflection, and experimentation. Observation collects facts; reflection combines them; experimentation verifies the result of that combination.

In order to get as much fame as one's father one has to much more able than he.

All abstract sciences are nothing but the study of relations between signs.

What is a monster? A being whose survival is incompatible with the existing order.

We swallow with one gulp the lie that flatters us, and drink drop by drop the truth which is bitter to us.

If the weather is too cold or rainy, I take shelter in the Regence Cafe, where I entertain myself by watching chess being played. Paris is the world center, and this cafe is the Paris centre for the finest skill at this game.

The world is the house of the strong. I shall not know until the end what I have lost or won in this place, in this vast gambling den where I have spent more than sixty years, dice box in hand, shaking the dice.

Gaiety is a quality of ordinary men. Genius always presupposes some disorder in the machine.

In order to shake a hypothesis, it is sometimes not necessary to do anything more than push it as far as it will go.

Our observation of nature must be diligent, our reflection profound, and our experiments exact. We rarely see these three means combined; and for this reason, creative geniuses are not common.

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.

The pit of a theatre is the one place where the tears of virtuous and wicked men alike are mingled.

We are constantly railing against the passions; we ascribe to them all of man's afflictions, and we forget that they are also the source of all his pleasures.

The first step towards philosophy is incredulity.

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

Good music is very close to primitive language.

If there is one realm in which it is essential to be sublime, it is in wickedness. You spit on a petty thief, but you can't deny a kind of respect for the great criminal.

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!