[About Pierre de Fermat] It cannot be denied that he has had many exceptional ideas, and that he is a highly intelligent man. For my part, however, I have always been taught to take a broad overview of things, in order to be able to deduce from them general rules, which might be applicable elsewhere.

With me, everything turns into mathematics.

Give me extension and motion and I will construct the universe.

Perfect numbers like perfect men are very rare.

I hope that posterity will judge me kindly, not only as to the things which I have explained, but also to those which I have intentionally omitted so as to leave to others the pleasure of discovery.

The two operations of our understanding, intuition and deduction, on which alone we have said we must rely in the acquisition of knowledge.