The chief cause of human errors is to be found in the prejudices picked up in childhood.

Science is practical philosophy.

The reading of all good books is like a conversation with the finest minds of past centuries.

But I cannot forget that, at other times I have been deceived in sleep by similar illusions; and, attentively considering those cases, I perceive so clearly that there exist no certain marks by which the state of waking can ever be distinguished from sleep, that I feel greatly astonished; and in amazement I almost persuade myself that I am now dreaming.

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

The principal effect of the passions is that they incite and persuade the mind to will the events for which they prepared the body.

Good sense is, of all things among men, the most equally distributed; for every one thinks himself so abundantly provided with it, that those even who are the most difficult to satisfy in everything else, do not usually desire a larger measure of this quality than they already possess.