Denis Diderot

I picture the vast realm of the sciences as an immense landscape scattered with patches of dark and light. The goal towards which we must work is either to extend the boundaries of the patches of light, or to increase their number. One of these tasks falls to the creative genius; the other requires a sort of sagacity combined with perfectionism.

The most dangerous madmen are those created by religion, and ... people whose aim is to disrupt society always know how to make good use of them on occasion.

Only passions, great passions, can elevate the soul to great things.

If you want me to believe in God, you must make me touch him.

One swallows the lie that flatters, but sips the bitter truth drop by drop.

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

Scepticism is the first step towards truth.

How had they met? By chance, like everybody else. What were there names? What's it to you? Where were they coming from? From the nearest place. Where were they going? Does anyone really know where they're going?

You live as if you were destined to live forever, no thought of your frailty ever enters your head, of how much time has already gone by you take no heed. You squander time as if you drew from a full and abundant supply, so all the while that day which you bestow on some person or thing is perhaps your last. You have all the fears of mortals and all the desires of immortals_ What foolish forgetfulness of mortality to defer wise resolutions to the fiftieth or sixtieth year, and to intend to begin life at a point to which few have attained.

Man will never be free until the last king is strangled with the entrails of the last priest.

There are things I can't force. I must adjust. There are times when the greatest change needed is a change of my viewpoint.

When superstition is allowed to perform the task of old age in dulling the human temperament, we can say goodbye to all excellence in poetry, in painting, and in music.

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

Morals are in all countries the result of legislation and government they are not African or Asian or European: they are good or bad.

You have to make it happen.

Although a man may wear fine clothing, if he lives peacefully; and is good, self-possessed, has faith and is pure; and if he does not hurt any living being, he is a holy man.

Patriotism is an ephemeral motive that scarcely ever outlasts the particular threat to society that aroused it.

Only passions, great passions can elevate the soul to great things.