I think therefore I exist

Of all things, good sense is the most fairly distributed: everyone thinks he is so well supplied with it that even those who are the hardest to satisfy in every other respect never desire more of it than they already have

Good sense is of all things in the world the most equally distributed, for everybody thinks he is so well supplied with it, that even those most difficult to please in all other matters never desire more of it than they already possess

Each problem that I solved became a rule, which served afterwards to solve other problems

Perfect numbers like perfect men are very rare

Except our own thoughts, there is nothing absolutely in our power

I hope that posterity will judge me kindly, not only as to the things which I have explained, but also to those which I have intentionally omitted so as to leave to others the pleasure of discovery

An optimist may see a light where there is none, but why must the pessimist always run to blow it out

It is not enough to have a good mind; the main thing is to use it well

A state is better governed which has few laws, and those laws strictly observed