Our sun enlightens the planets that belong to him; why may not every fixed star also have planets to which they give light?

They will have the World to be in Large, what a Watch is in Small; which is very regular, and depends only upon the just disposing of the several Parts of the Movement.

It is the passions that do and undo everything.

Nothing can be more destructive to ambition, and the passion for conquest, than the true system of astronomy. What a poor thing is even the whole globe in comparison of the infinite extent of nature!

If I had my hand full of truth, I would take good care how I opened it.

A true philosopher is like an elephant; he never puts the second foot down until the first one is solidly in place.

Nature intends that, at fixed periods, men should succeed each other by the instrumentality of death. We shall never outwit Nature; we shall die as usual.