I did not imitate the skeptics who doubt only for doubting's sake, and pretend to be always undecided; on the contrary, my whole intention was to arr….

Let whoever can do so deceive me, he will never bring it about that I am nothing, so long as I continue to think I am something..

Even those who have the weakest souls could acquire absolute mastery over all their passions if we employed sufficient ingenuity in training and guid….

I am indeed amazed when I consider how weak my mind is and how prone to error..

The rainbow is such a remarkable phenomenon of nature, and its cause has been so meticulously sought after by inquiring minds throughout the ages, th….

This result could have been achieved either by his [God] endowing my intellect with a clear and distinct perception of everything about which I would….

Archimedes, that he might transport the entire globe ... demanded only a point that was firm and immovable; so also, I shall be entitled to entertain….

... regard this body as a machine which, having been made by the hand of God, is incomparably better ordered than any machine that can be devised by ….

In philosophy, when we make use of false principles, we depart the farther from the knowledge of truth and wisdom exactly in proportion to the care w….

Even the mind depends so much on temperament and the disposition of one's bodily organs that, if it is possible to find a way to make people generall….

I experienced in myself a certain capacity for judging which I have doubtless received from God, like all the other things that I possess; and as He ….

The only thing that I know, is that I know nothing.

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

Common sense is the most widely shared commodity in the world, for every man is convinced that he is well supplied with it..

Everything is self-evident..

All is to be doubted..

I think; therefore I am..

For each of us there is a set limit to our intellectual powers which we cannot pass..

Divide each difficulty into as many parts as is feasible and necessary to resolve it..

Although my knowledge grows more and more, nevertheless I do not for that reason believe that it can ever be actually infinite, since it can never re….

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