Modern empiricism came to articulate expres sion first in Francis Bacon, who insisted upon the abandonment of the deductive, a priori sin-ciliation of the sehoolmen. and on the neces sity of studying nature without bias. Hobbes Bacon in urging the necessity of a philosophy of experience; lint being especially interested in human nature. and yet lacking the data for an inductive study of society. he allowed himself to construct society out of imaginary isolated human beings and to palm off this fiction for fact.
Modern rationalism began with Descartes, who is often called the father of modern philosophy. Ile likewise emphasized the necessity of beginning anew, but, unlike Bacon, he looked to the inner nature of self-consciousness for the principles that can build np the structure and furnish the certainty of knowledge. The ('artesian system is rationalistic; the method for advancing our knowledge was thought to consist in letting the light of reason shine forth. This was accom plished by the application of mathematical method to metaphysics. with the result of bring ing out the innate truths and principles of rea son. In this way we become assured. so Descartes argued, of our own existence, of the existence of God, and of that of the material universe. Descartes sharply separated mind and matter; mind is thinking, unextended substance; matter is unconscious, extended substance. Two great problems are therefore handed down to his immediate followers. What is the relation be tween mind and matter in general, and the soul and body in particular? And what is the rela tion between the soul and God? Geulinex, the founder of Occasionalism (q.v.), answers the former question by saying that God acts in the individual, intervening on each occasion, to main tain the parallel between mind and body. God is the real subject of human acts, the individual being but a nominal subject. The second problem is taken up by 1Malebranche, who maintains that God thinks in the individual. The individual is nothing but the mode of God's being. The mind is in God, and in Him views everything in its eternal significance. Spinoza carries out Cartesianism to its logical conclusion. Sub stance is that which exists independently. Hence the infinite alone, God, is true substance. Mind and matter are two attributes of the one divine substance. They are known to us as the
parallel manifestations of the hidden substantial identity in God. Spinoza develops his system by pure deduct ire reasoning, following the procedure of geometrical demonstrations. He thus exhibits the ideal method of rationalism, which regards reason, working solely on its own inner prin ciples, as capable of discovering the true nature of reality. The moral and physical parts of the universe follow from these principles with the same rigid necessity as the dcmonstranda of geometry follow from its axioms. .Joyful resig nation to this rationalistic determinism is the essence of morality. Spinozism reduces the dualism of mind and matter to a common prin ciple and results in pantheistic monism (q.v.). Leibnitz endeavors to solve the paradox of Spino zism that unextended and extended substances are ultimately identical. As a rationalist be sides with Spinoza; as an individualist he sides with Locke. Leibnitz's substance is not that which crisis through itself, but rather that which arts through itself. Reality consists of an infinite number of monads (q.v.), which are unextended, ideal activities, centres of original forces, or formal atoms. Eaeh atom is self-contained and cannot he modified from without. Spinoza sur renders the reality of individuals to the principle of nnity. This unity Leibnitz breaks up into a plurality of independent, self-active monads. But the multiplicity is synthetized by the Leibnitzian principle of continuity and the law of prOstab lished harmony (q.v.). All the monads belong to an organized system, and each mirrors or repre sents the universe. The individuals are not isolated, but belong to an organic whole. Cod, the supreme monad, is pure activity, while finite monads are in a state of imperfect realization. They are not completely active. It is the pas sivity of finite monads that gives rise to confused perceptions, which cause the appearance of an extended, material world. These fundamental principles of Leibnitz's system are sacrificed by his f(Thower, Wolff, who adopted merely the rationalistic method of his master and reduced philosophy once. more to scholastic form. This was the eulmination of dogmatic rationalism on the Continent.