One might argue that the very form of The Ethics, written in the highly formalized “geometrical style” inspired by Euclid’s Elements, is partially designed for the practical purpose of keeping out any but the most gifted of readers, rigorously cerebral and patiently rational.

Spinoza’s ambitions on behalf of reason are staggering: he aims to give us a rigorously proved view of reality, which view will yield us, if only we will assimilate it, a life worth living. It will transform our emotional substance, our very selves. The truth shall set us free. His methodology for exposing the nature of reality was inspired by one of the strands that the seventeenth century’s men of science were weaving into what we now refer to as the scientific method, that magnificently subtle, supple, and successful blend of mathematical deduction and empirical induction. Spinoza was keenly interested and involved in the intellectual innovations that we now look back on as constituting the birth of modern science. His inspiration came from the mathematical component of modern science, not its empiricism. The methodology he believed could reveal it all was strictly deductive, which is not the way that science ultimately went. (Still, there are contemporary physicists and cosmologists who are inspired by the Spinozist ideal of “a theory of everything,” one in which the mathematics alone would determine its truth. String theorists, in particular, pursue physics almost entirely as a deductive endeavor, letting their mathematics prevail over niggling empirical questions. The spirit motivating them is Spinozism, which sometimes makes other scientists question whether what string theorists are up to really qualifies as science at all.)

But if the claims Spinoza makes on behalf of pure reason can strike us as staggering, there are also, staggeringly, a number of propositions that he produced from out of his deductive system that have been, centuries later, scientifically vindicated.