Whenever anyone has offended me, I try to raise my soul so high that the offense cannot reach it.

The greatest minds, as they are capable of the highest excellencies, are open likewise to the greatest aberrations; and those who travel very slowly may yet make far greater progress, provided they keep always to the straight road, than those who, while they run, forsake it.

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

Travelling is almost like talking with those of other centuries.

And as it is the most generous souls who have most gratitude, it is those who have most pride, and who are most base and infirm, who most allow themselves to be carried away by anger and hatred.

If ... it is not in my power to arrive at the knowledge of any truth, I may at least do what is in my power, namely, suspend judgement.

If we possessed a thorough knowledge of all the parts of the seed of any animal (e.g. man), we could from that alone, be reasons entirely mathematical and certain, deduce the whole conformation and figure of each of its members, and, conversely if we knew several peculiarities of this conformation, we would from those deduce the nature of its seed.