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!

To despise theory is to have the excessively vain pretension to do without knowing what one does, and to speak without knowing what one says.

It is high time for me to depart, for at my age I now begin to see things as they really are.

A well-cultivated mind is, so to speak, made up of all the minds of preceding ages; it is only one single mind which has been educated during all this time.

I shall leave the world without regret, for it hardly contains a single good listener.

Let us be well assured of the Matter of Fact, before we trouble our selves with enquiring into the Cause. It is true, that this Method is too slow for the greatest part of Mankind, who run naturally to the Cause, and pass over the Truth of the Matter of Fact.

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