The ideas of rationalist philosophers Baruch Spinoza and Gottfried Leibniz are examined in this program by philosophy Anthony Quinton. Spinoza favors a pantheistic God who has matter and mind as two attributes, and who is the ultimate substance and explanation of the world. Leibniz sees the real world as consisting of an infinity of things purely spiritual, where everything, including space, is a phenomenon—a by-product of areal world with an infinite array of spiritual centers. Both philosophers construct a world that is very different form what the average person perceives, and both reject Cartesian duality.