3. RATIONAL PSYCHOLOGY.--The soul is that within us which is self-conscious. In the self-consciousness of the soul are itself and other objects. Consciousness is either clear or indistinct. Clear consciousness is thought. The soul is a simple incorporeal substance. There dwells within it a power to represent to itself a world. In this sense brutes also may have a soul, but a soul which possesses understanding and will is mind, and mind belongs alone to men. The soul of man is a mind joined to a body, and this is the distinction between men and superior spirits. The movements of the soul and of the body harmonize with each other by virtue of the preëstablished harmony. The freedom of the human soul is the power according to its own arbitrament, to choose of two possible things that which pleases it best. But the soul does not decide without motives, it ever chooses that which it holds to be the best. Thus the soul would seem impelled to its action by its representations, but the understanding is not constrained to its representations of that which is good and bad, and hence also the will is not constrained, but free. As a simple being the soul is indivisible, and hence incorruptible; the souls of brutes, however, have no understanding, and hence enjoy no conscious existence after death. This belongs alone to the human soul, and hence the human soul alone is immortal. 4. NATURAL THEOLOGY.—Wolff uses here the cosmological argument to demonstrate the existence of a God. God might have made different worlds, but has preferred the present one as the best. This world has been called into being by the will of God. His aim in its creation was the manifestation of his own perfection. Evil in the world does not spring from the Divine will, but from the limited being of human things. God permits it only as a means of good. This brief aphoristic exposition of Wolff’s metaphysics, shows how greatly it is related to the doctrine of Leibnitz. The latter, however, loses much of its speculative profoundness by the abstract and logical treatment it receives in the hands of Wolff. For the most part, the specific elements of the monadology remain in the background; with Wolff, his simple beings are not representative like the Monads, but more like the Atoms. Hence there is with him much that is illogical and contradictory. His peculiar merit in metaphysics is ontology, which he has elaborated far more strictly than his predecessors. A multitude of philosophical terminations owe to him their origin, and their introduction into philosophical language.