So, Fabricius, I already have this: that the most true path of the planet [Mars] is an ellipse, which Dürer also calls an oval, or certainly so close to an ellipse that the difference is insensible.

Planets move in ellipses with the Sun at one focus.

Nature uses as little as possible of anything.

So long as the mother, Ignorance, lives, it is not safe for Science the offspring, to divulge the hidden causes of things.

Since we astronomers are priests of the highest God in regard to the book of nature, it befits us to be thoughtful, not of the glory of our minds, but rather, above all else, of the glory of God.

The chief aim of all investigations of the external world should be to discover the rational order and harmony which has been imposed on it by God and which He revealed to us in the language of mathematics.

If my false figures came near to the facts, this happened merely by chance ... These comments are not worth printing. Yet it gives me pleasure to remember how many detours I had to make, along how many walls I had to grope in the darkness of my ignorance until I found the door which lets in the light of the truth ... In such manner did I dream of the truth.