Because reason...is the only thing that makes us men, and distinguishes us from the beasts, I would prefer to believe that it exists, in its entirety, in each of us.

A person has two passions for love and abhorrence. A big disposition to excessiveness has just a love, because it is more ardent and stronger.

Doubt is the origin of wisdom

Science is practical philosophy.

I concluded that I might take as a general rule the principle that all things which we very clearly and obviously conceive are true: only observing, however, that there is some difficulty in rightly determining the objects which we distinctly conceive.

In the matter of a difficult question it is more likely that the truth should have been discovered by the few than by the many.

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.