To live without philosophizing is in truth the same as keeping the eyes closed without attempting to open them.

There is a great difference between mind and body insomuch as body is by nature always divisible, and the mind is entirely indivisible.

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 arrive at a certainty, and to dig away the drift and the sand until I reached the rock or the clay beneath.

You just keep pushing. You just keep pushing. I made every mistake that could be made. But I just kept pushing.

Divide each difficulty at hand into as many pieces as possible and as could be required to better solve them.

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 reach a point so high that it will be unable to attain any greater increase.

These long chains of perfectly simple and easy reasonings by means of which geometers are accustomed to carry out their most difficult demonstrations had led me to fancy that everything that can fall under human knowledge forms a similar sequence; and that so long as we avoid accepting as true what is not so, and always preserve the right order of deduction of one thing from another, there can be nothing too remote to be reached in the end, or to well hidden to be discovered.