  Spinoza’s account of the eternal verities marks a similar rationalistic advance over Descartes’s metaphysics. For Spinoza, God is just substance simpliciter. He lacks volition and personality; his only characteristics are pure being, infinity, necessity, and activity. While Spinoza agreed with Descartes that God is the cause of all things, he regarded him not as a transeunt cause, creating the universe “from the outside” through an act of will, but as an immanent cause, from whom the universe unfolds out of his own necessity. For Spinoza, all things therefore follow by logical (and not merely causal) necessity from God’s eternal and infinite nature. In this sense, not only mathematical truths but indeed such apparently contingent facts as Caesar’s having crossed the Rubicon are necessary truths for Spinoza. The difference between them is not the necessity of the truths themselves but rather the route that we take to arrive at them. While mathematical truths, for instance, are deducible by reason alone, Spinoza recognized that the finitude of human understanding prevents, or at least impedes, our similarly deducing empirical facts about the world. In contrast with some empiricists, who regard cause and effect as mere constant conjunction, for Spinoza, the relationship between cause and effect has the force of a logical entailment; empirical facts are themselves necessary truths. The universe is thus, in principle at least, perfectly intelligible to reason.