2. COSMOLOGY.—Wolff defines the world to be a series of changing objects, which exist conjointly and successively, but which are so connected together that one ever contains the ground of the other. Things are connected in space and in time. By virtue of this universal connection, the world is one united whole; the essence of the world consists in the manner of its connection. But this manner cannot be changed. It can neither receive any new ingredients nor lose any of those it possesses. From the essence of the world spring all its changes. In this respect the world is a machine. Events in the world are only hypothetically necessary in so far as previous events have had a certain character; they are accidental in so far as the world might have been directed otherwise. In respect to the question whether the world had a beginning in time, Wolff does not express himself explicitly. Since God is independent of time, but the world has been from eternity in time, the world therefore is in no case eternal in any sense like God. But according to Wolff, neither space nor time has any substantial being. Body is a connected thing composed of matter, and possessing a moving power within itself. The powers of a body taken together are called its nature, and the comprehension of all being is called nature in general. That which has its ground in the essence of the world is called natural, and that which has not, is supernatural, or a wonder. At the close of his cosmology, Wolff treats of the perfection and imperfection of the world. The perfection of a world consists in the harmony with each other of every thing which exists conjointly and successively. But since every thing has its separate rules, the individual must give up so much from its perfection as is necessary for the symmetry of the whole.