His Philosophy

It has been both asserted and denied that the thoughts developed in Spinoza's short life of forty-four years, and put forth anonymously after his death with such remarkable influence on the history of European speculation for at least the last one hundred and fifty years, were derived in large measure from his Jewish training and reading. The question is a very difficult one to decide, owing to the close-linked chain of Spinoza's thought, which he designedly made in his "Ethics" a continuous course of reasoning, each proposition being dependent upon the preceding, exactly after the manner of Euclid. In order to determine the extent of his Jewish indebtedness it is necessary, therefore, to attempt some slight sketch of his whole system. Apart from this object it deserves such exposition as the most influential body of doctrine ever produced by a Jew since Philo.
The key to Spinoza's philosophic system is to be found in his method of investigation as indicated in the fragmentary "De Intellectus Emendatione." Finding that none of the ordinary objects of man's desire—wealth, power, and the like—affords permanent satisfaction, Spinoza came to the conclusion that only the attainment of truth gives that increase of power and accompanying joy which can be described as true happiness or sal vation. Turning to the search for truth, he found the powers of the mind to be of a treble nature, each particular function yielding knowledge of various degrees of adequacy: (1) imagination, yielding only confused and inadequate ideas; (2) reason, giving the essences of things, and (3) intuition, disclosing the fundamental principles uniting those essences into a system and connecting individual things with those principles. The logical foundation of his whole system lies in the denial of the validity of all relative propositions, leaving the Absolute as the sole reality of the universe. On this see B. Russell, "Principles of Mathematics" (p. 448, Cambridge, 1903), which work is so far a justification of Spinoza's method in that it proves the possibility of deducing all the principles of pure mathematics and physics from a certain number of indefinables and indemonstrables. All turns with Spinoza, as with Descartes and the scholastics, on getting true and adequate knowledge of the essences of things. All the essences, when presented to the mind, carry with them a conviction of their own truth, and, as they can not contradict one another, they form a system of truths deduced from one principle as their primary cause. Such a principle can only be God, from whose qualities all the essences of things must flow as a matter of necessity, or, in other words, be "caused," since Spinoza does not distinguish between logical dependence anddynamic causation. In this way his logic passes over into his metaphysics, and in attempting to determine the cause of things, from the contemplation of which he is to obtain salvation, Spinoza has to determine the essences of things and their relation to the Highest Reality.