The pleasure we obtain from music comes from counting, but counting unconsciously. Music is nothing but unconscious arithmetic.

God makes nothing without order, and everything that forms itself develops imperceptibly out of small parts.

I hold that it is only when we can prove everything we assert that we understand perfectly the thing under consideration.

..This is why the ultimate reason of things must lie in a necessary substance, in which the differentiation of the changes only exists eminently as in their source; and this is what we call God.

I also take it as granted that every created thing, and consequently the created monad also, is subject to change, and indeed that this change is continual in each one.

The world is not a machine. Everything in it is force, life, thought.

And there must be simple substances, because there are compounds; for the compound is nothing but a collection or aggregatum of simples.