It has long seemed ridiculous to me to suppose that the nature of things has been so poor and stingy that it provided souls only to such a trifling mass of bodies on our globe, like human bodies, when it could have given them to all, without interfering with its other ends.

The present is saturated with the past and pregnant with the future.

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

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

God, possessing supreme and infinite wisdom, acts in the most perfect manner, not only metaphysically, but also morally speaking, and ... with respect to ourselves, we can say that the more enlightened and informed we are about God's works, the more we will be disposed to find them excellent and in complete conformity with what we might have desired.

He who understands Archimedes and Apollonius will admire less the achievements of the foremost men of later times.

When a truth is necessary, the reason for it can be found by analysis, that is, by resolving it into simpler ideas and truths until the primary ones are reached. It is this way that in mathematics speculative theorems and practical canons are reduced by analysis to definitions, axioms and postulates.