To command their professors of astronomy to refute their own observations is to command them not to see what they do see and not to understand what they do understand.

Holy Writ was intended to teach men how to go to Heaven not how the heavens go.

They seemed to forget that the increase of known truths stimulates the investigation, establishment and growth of the arts; not their dimination or destruction.

In the sciences, the authority of thousands of opinions is not worth as much as one tiny spark of reason in an individual man.

One can understand nature only when one has learned the language and the signs in which it speaks to us; but this language is mathematics and these signs are methematical figures.

God is known by nature in his works, and by doctrine in his revealed word.

Some, merely to contradict what I had said, did not scruple to cast doubt upon things they had seen with their own eyes again and again.