I am indeed amazed when I consider how weak my mind is and how prone to error.

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

We do not describe the world we see, we see the world we can describe.

Variant: When it is not in our power to follow what is true, we ought to follow what is most probable.

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.

It is contrary to reasoning to say that there is a vacuum or space in which there is absolutely nothing.

The mind effortlessly and automatically takes in new ideas, which remain in limbo until verified or rejected by conscious, rational analysis.