Nature uses as little as possible of anything.

The heavenly motions... are nothing but a continuous song for several voices, perceived not by the ear but by the intellect, a figured music which sets landmarks in the immeasurable flow of time.

Nature loves simplicity and unity.

It may be well to wait a century for a reader, as God has waited six thousand years for an observer.

Geometry has two great treasures; one is the Theorem of Pythagoras; the other, the division of a line into extreme and mean ratio. The first we may compare to a measure of gold; the second we may name a precious jewel.

A most unfailing experience... of the excitement of sublunary (that is, human) natures by the conjunctions and aspects of the planets has instructed and compelled my unwilling belief.

Astronomy would not provide me with bread if men did not entertain hopes of reading the future in the heavens.