No person ever had the idea of infinity so profoundly as did Spinoza. His idea of infinity is not merely that of the infinity of time and space, which indeed affords a tremendous variety of possible constructions, since space and time are each infinite. To Spinoza the infinity of the substance is much more than these possible combinations of time and space, for corresponding to the time and space series is a series of mental states. Every event has a reason. Every one of the infinity of events in the world of extension is paralleled by some state of thought. But this is by no means the whole story about Spinoza’s conception of infinity. Besides the infinite world of time and space and the infinite world of corresponding thought, the substance to Spinoza possesses an infinity of other attributes, each of which is infinite. Spinoza piles up infinities upon infinities, and thus conceives the substance as an infinity in an overwhelming sense. Only two of the infinite modes appear to our limited human discernment: the infinity of the mode of extension, and the infinity of the mode of thought. Spinoza begins at once to tell us about the forms in which the all-inclusive God appears to us. First, the substance has two attributes, thought and extension. An attribute is “that which the intellect perceives as constituting the essence of the substance.” Each attribute in its turn manifests itself in modes: thought appears in the modes of intellect and will, extension in the modes of rest and motion. Substance = God. ┌────────┴────────┐ Attributes = Thought Extension. ┌────┴────┐ ┌───┴───┐ Modes = Intellect Will Motion Rest. This bare skeleton of our rich and varied world appears very much the same as that which one might find beneath Descartes’ philosophy. However, Spinoza’s conception of substance transforms it into a framework of a very different kind of philosophy. Since God is the inclusive reality of it all, we have here a pantheism instead of a dualism. The antithesis which in Descartes’ philosophy was between extension and thought, now in Spinoza’s teaching is between God and other things.