There comes a moment during which almost every girl or boy falls into melancholy; they are tormented by a vague inquietude which rests on everything and finds nothing to calm it. They seek solitude; they weep; the silence to be found in cloister attracts them: the image of peace that seems to reign in religious houses seduces them. They mistake the first manifestations of a developing sexual nature for the voice of God calling them to Himself; and it is precisely when nature is inciting them that they embrace a fashion of life contrary to nature's wish.

A thing is not proved just because no one has ever questioned it. What has never been gone into impartially has never been properly gone into. Hence scepticism is the first step toward truth. It must be applied generally, because it is the touchstone.

What a fine comedy this world would be if one did not play a part in it.

The philosopher forms his principles on an infinity of particular observations. He does not confuse truth with plausibility, he takes for truth what is true, for false what is false, for doubtful what is doubtful, and probable what is probable. The philosophical spirit is thus a spirit of observation and accuracy.

You can be sure that a painter reveals himself in his work as much as and more than a writer does in his.

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

Fanaticism is just one step away from barbarism.