Wonder is the first of all the passions.

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.

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

When I consider this carefully, I find not a single property which with certainty separates the waking state from the dream. How can you be certain that your whole life is not a dream?

Every man is indeed bound to do what he can to promote the good of others, and a man who is of no use to anyone is strictly worthless.

I have concluded the evident existence of God, and that my existence depends entirely on God in all the moments of my life, that I do not think that the human spirit may know anything with greater evidence and certitude.

It is not enough to have a good mind. The main thing is to use it well.