There is not a sprig of grass that shoots uninteresting to me.

Where a new invention promises to be useful, it ought to be tried.

Never trouble another for what you can do yourself

I should . . . prefer swallowing one incomprehensibility rather than two. It requires one effort only to admit the single incomprehensibility of matter endowed with thought, and two to believe, first that of an existence called spirit, of which we have neither evidence nor idea, and then secondly how that spirit, which has neither extension nor solidity, can put material organs into motion.

Though [the people] may acquiesce, they cannot approve what they do not understand.

Everyone must act according to the dictates of his own reason.

The past stays put, I just keep moving farther away from it.