In God there is an infinitude of things which I cannot comprehend, nor possibly even reach in any way by thought; for it is the nature of the infinite that my nature, which is finite and limited, should not comprehend it.

I can doubt everything, except one thing, and that is the very fact that I doubt. Simply put - I think, therefore I am

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.

There is nothing more ancient than the truth.

Whatever I have up till now accepted as most true and assured I have gotten either from the senses or through the senses. But from time to time I have found that the senses deceive, and it is prudent never to trust completely those who have deceived us even once.

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

I accept no principles of physics which are not also accepted in mathematics.