I write the book, to be read, either now or by posterity. Which, I care not. It may well wait a century for a reader, as long as God waited six thousand years for a discoverer.

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.

I much prefer the sharpest criticism of a single intelligent man to the thoughtless approval of the masses.