27© LEIBNITZ. Cartesian and the atomistic conceptions. The Cartesians are right when they make the concept of substance the cardinal point in metaphysics and explain it by the concept of inde- pendence. But they are wrong in their further definition of this second concept. If we take independence in the sense of unlimitedness and aseity, we can speak, as the example of Spinoza shows, of only one, the divine substance. If the Spinozistic result is to be avoided, we must substi- tute independent action for independent existence, self- activity for self-existence. Substance is not that which exists through itself (otherwise there would be no finite sub- stances), but that which acts through itself, or that which contains in itself the ground of its changing states. Sub- stance is to be defined by active force,* by which we mean something different from and better than the bare possibility or capacity of the Scholastics. The potentia sive facultas, in order to issue into action, requires positive stimulation from without, while the vis activa (like an elastic body) sets itself in motion whenever no external hindrance opposes. Substance is a being capable of action {la substance est un it re capable d' action). With the equation of activity and existence {quod nan agit, non existit) the substantiality which Spinoza had taken away from individual things is restored to them : they are active, consequently, in spite of their limited- ness, substantial beings {quod agit, est substantia singularis). Because of its inner activity every existing thing is a deter- minate individual, and different from every other being. Substance is an individual being endowed with force. The atomists are right when they postulate for the expla- nation of phenomenal bodies simple, indivisible, eternal units, for every composite consists of simple parts. But they are wrong when they regard these invisible, minute corpuscles, which are intended to subserve this purpose as indivisible: everything that is material, however small it be, is divisible to infinity, nay, is in fact endlessly divided. If we are to find indivisible units, we must pass
- Francis Glisson (1596-1677, professor of medicine in Cambridge and Lon-
don) had as early as 1671, conceived substances as forces in his treatise De Natura Substantia Energetica. That Glisson influenced Leibnitz, as maintained by H. Marion (Paris, 1880), has not been proven ; of. L. Stein, p. 184.
