Every present state of a simple substance is the natural consequence of its preceding state, in such a way that its present is big with its future.

God's relation to spirits is not like that of a craftsman to his work, but also like that of a prince to his subjects.

Nothing is more important than to see the sources of invention which are, in my opinion more interesting than the inventions themselves.

It's easier to be original and foolish than original and wise.

If we were magically shrunk and put into someone's brain while she was thinking, we would see all the pumps, pistons, gears and levers working away and we would be able to describe the workings completely, in mechanical terms, thereby completely describing the thought processes of the brain. But that description would not contain any mention of thought! It would contain nothing but descriptions of pumps, pistons, levers!

The larger the mass of collected things, the less will be their usefulness. Therefore, one should not only strive to assemble new goods from everywhere, but one must endeavor to put in the right order those that one already possesses.

Thus God alone is the primary Unity, or original simple substance, from which all monads, created and derived, are produced.