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

Scepticism is the first step towards truth.

The first promise exchanged by two beings of flesh was at the foot of a rock that was crumbling into dust; they took as witness for their constancy a sky that is not the same for a single instant; everything changed in them and around them, and they believed their hearts free of vicissitudes. O children! always children!

I have only a small flickering light to guide me in the darkness of a thick forest. Up comes a theologian and blows it out.

A thing is not proved because no one has ever questioned it... Skepticism is the first step toward truth.

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

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?