Man was born to live with his fellow human beings. Separate him, isolate him, his character will go bad, a thousand ridiculous affects will invade his heart, extravagant thoughts will germinate in his brain, like thorns in an uncultivated land.

Oh! how near are genius and madness! Men imprison them and chain them, or raise statues to them.

It is not the man who is beside himself, but he who is cool and collected,--who is master of his countenance, of his voice, of his actions, of his gestures, of every part of his play,--who can work upon others at his pleasure.

All things must be examined, debated, investigated without exception and without regard for anyone's feelings... We must run roughshod over all these ancient puerilities, overturn the barriers that reason never erected, give back to the arts and sciences the liberty that is so precious to them.

Fanaticism is just one step away from barbarism.

Those who fear the facts will forever try to discredit the fact-finders.

Evil always turns up in this world through some genius or other.