I hold that it is only when we can prove everything we assert that we understand perfectly the thing under consideration.
Gottfried LeibnizIt is God who is the ultimate reason things, and the Knowledge of God is no less the beginning of science than his essence and will are the beginning of things.
Gottfried LeibnizBut it is the knowledge of necessary and eternal truths which distinguishes us from mere animals, and gives us reason and the sciences, raising us to knowledge of ourselves and God. It is this in us which we call the rational soul or mind.
Gottfried Leibniz