Gottfried Wilhelm Leibniz — "He who does not act does not exist."

"The passing condition which involves and represents a multiplicity in the unity, or in the simple substance, is nothing else than what is called perception. This should be carefully distinguished from…"

"The actual world is the most beautiful possible."

"The monads are the true atoms of nature, and, in a word, the elements of things."

"Philosophy consists mostly of kicking up a lot of dust and then complaining that you can't see anything."

"If geometry were as much opposed to our passions and present interests as is ethics, we should contest it and violate it but little less, notwithstanding all the demonstrations of Euclid and Archimede…"