Those who study the stars have God for a teacher.

Now it is quite clear to me that there are no solid spheres in the heavens, and those that have been devised by the authors to save the appearances, exist only in the imagination.

So mathematical truth prefers simple words since the language of truth is itself simple.

Behold, directly overhead, a certain strange star was suddenly seen . . . Amazed, and as if astonished and stupified, I stood still

It was not just the Church that resisted the heliocentrism of Copernicus.

When I had satisfied myself that no star of that kind had ever shone before, I was led into such perplexity by the unbelievability of the thing that I began to doubt the faith of my own eyes.

There is something eccentric in the orbit of Mars.

The mouse is wise, but the cat is wiser.

And when statesmen or others worry him [the scientist] too much, then he should leave with his possessions. With a firm and steadfast mind one should hold under all conditions, that everywhere the earth is below and the sky above and to the energetic man, every region is his fatherland.

From his observations, he concluded that it [Tycho's supernova] was not some kind of comet or a fiery meteor, whether these be generated beneath the Moon or above the Moon, but that it is a star shining in the firmament itself - one that has never previously been seen before our time, in any age since the beginning of the world.

May I not seem to have lived in vain.