‘affections’ of substance . All particular things in space are the modes of God in the attribute extension: all particular thoughts and feelings are modes of God Spinoza's philosophy finds its most adequate expression in his great work, Ethica Ordine Geometrico Demonstrata (posthumously published in 1677). The basis from which it was developed was mainly Cartesianism. Certainly from Descartes he derived his empirical rationalism and his conception of exact demonstration. This latter, on the analogy of geometrical demonstrations, consisted of a series of axioms Nevertheless, there are few philosophers in whom the personal element is more distinctive. The very fact of Spinoza's severance from his own race and religion, together with his failure to adopt Christian thought, made the individuality of his system the more inevitable; he was bound by no tradition and so followed to the fullest the instincts of his reason. He was influenced by Descartes in method and probably by Bruno in his pantheism, but his system is still his own to a degree seldom true in the history of philosophy. This system is a thorough-going and complicated pantheism. The universe is identical with God, who is the substance of all things. The conception of substance (which Spinoza inherited from the Scholastics) is not that of a material reality, but of a logical subject — the self-sufficient and comprehensive basis for all reality, capable of sustaining as its attributes all temporal existences. Spinoza recognized the possible existence of an infinite number of such attributes, but held that only two kinds are known to us — extension, or the world of material things, and thought. These two comprehend existence and they include all that exists in a real and palpable way, at least so far as human knowledge is concerned. The idea of extension as the gist of physical reality, and of thought as a non-extended reality, Spinoza derived from Descartes. But Descartes made each of these independent substances and conceded to them the power of causal interaction — mind acting upon body and vice versa . Spinoza, as we have seen, makes both forms of reality dependent upon an ultimate substance — God — in which is their existence. Furthermore, he denies their power of causal interaction. Cause and effect in his conception are always similar; extension and thought are wholly dissimilar; therefore their causal interrelation is impossible. Causation may subsist between individual objects in the attribute extension, that is, between physical bodies, or between individual ideas in the attribute thought, but not between ideas and things. To explain the apparent causal interactions of the latter Spinoza resorted to an elaborate theory of parallelism. Every idea has a physical counterpart in the attribute extension; every physical object has its idea. This is not only true for the individuals in each attribute, but nocossarily for their relations also. Hence parallel with every physical causal series there is an ideational causal series reduplicating it; neither is dependent upon the other, but both depend upon the divine substance made manifest through them. The individuality of things, whether ideas or physical objects, Spinoza explained as particular modes or ‘affections’ of substance. All particular things in space are the modes of God in the attribute extension: all particular thoughts and feelings are modes of God in the attribute thought. The modes are natura naturata ; substance or God is natura naturans . The modes are ephemeral and their existence assumes temporal form; God is eternal, outlasting all attributive changes. The most distinctive difference between Spinoza's world of existences and his world of essences is that the former exists in time, while the latter has no temporal being. But mortality can pertain only to temporal being; therefore the world of essences, being timeless, must be immortal. Furthermore, the world of essences is a world of immanent being. Every existence has a universal or essential character, though to realize this character it must transcend its own intrinsic form, that is, free itself from whatever gives it particularity. The world of essences thus has a kind of being within the world of existences — as the immanent cause of the latter — though it does not share its temporal limitation. Now this is precisely true of the divine substance; and so it is that the world of essences represents the essential nature of God. Immanent causation means self-causation, and that which is self-determined is free. From this reasoning Spinoza derived his doctrine of freedom to be won in the world of essences. Existence in the attribute is bondage, for each existent thing is determined by its own causal series; every particular object or idea is subject to other objects or ideas, and the form of its being is determined by them. Only in non-temporal, self-caused being, that is, in the universal and immanent, is freedom possible; only by identification with the eternal verities, with substance or God, is immortality — and with it peace — to be obtained. From this conception springs Spinoza's ethical doctrine, developed in the third, fourth, and fifth parts of the Ethica . In its practical form his teaching assumes that everything, so far as in it lies, strives to remain in its own being. Not only metaphysicians, but poets such as Goethe, Wordsworth, and Shelley, have gone to him for inspiration, and the essence of his thought has been in large part appropriated in the poetic pantheism of modern interpretations of nature. Complete editions of Spinoza's works have been published by Paulus (1802-03), by Bonden (1843-46), and by Van Volten and Land (1882-82). English translations have been made for the Bohn Library (1883), by White and Stanlay, the Ethics (London, 1883), by Fullerton, The Philosophy of Spinoza , selections with introduction (New York, 2d ed.