Leibniz never married; he had considered it at the age of fifty; but the person he had in mind asked for time to reflect. This gave Leibniz time to reflect, too, and so he never married.

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

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.

Since the princes take the Earth for their own, it's fair that the philosophers reserve the sky for themselves and rule there, but they should never permit the entry of others.

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.

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.

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