[Believers] are but triflers who, when they cannot explain a thing, run back to the will of God; this is, truly, a ridiculous way of expressing ignorance.

Only that thing is free which exists by the necessities of its own nature, and is determined in its actions by itself alone.

True knowledge of good and evil as we possess is merely abstract or general, and the judgment which we pass on the order of things and the connection of causes, with a view to determining what is good or bad for us in the present, is rather imaginary than real.

What everyone wants from life is continuous and genuine happiness.

The endeavor to understand is the first and only basis of virtue.

A free man, who lives among ignorant people, tries as much as he can to refuse their benefits. .. He who lives under the guidance of reason endeavours as much as possible to repay his fellow's hatred, rage, contempt, etc. with love and nobleness.

The greater emotion with which we conceive a loved object to be affected toward us, the greater will be our complacency.