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

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

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.

The Art of Flying is but newly invented, twill improve by degrees, and in time grow perfect; then we may fly as far as the Moon.

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

Mathematicians are like lovers. Grant a mathematician the least principle, and he will draw from it a consequence which you must also grant him, and from this consequence another.

Behold a universe so immense that I am lost in it. I no longer know where I am. I am just nothing at all. Our world is terrifying in its insignificance.