SUBSTANCE
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SUBSTANCE
the fonner is the individual thing — substance properly
so called; the latter designates the universal essence
or nature as contained in genus and species. And,
again, substance is either complete, e. g. man, or in-
complete, e. g. the soul, which, though possessing
existence in itself, is united with the body to form the
specifically complete human being. Tlio principal
division, however, is that between material substance
(all corporeal things) and spiritual substance, i. e. the
soul and the angelic spirits. The latter are often
called suhstantice separata; to signify that they are
separate from matter, i. e. neither actually conjoined
with a material organism nor requiring such union
as the natural complement of their being (St. Thomas,
"Contra Gentcs", II, 91 sqq.). St. Thomas further
teaclies that the name sub.ita7ice cannot properlj' be
applied to God, not only because He is not the sub-
ject of any accidents, but also because in Him essence
and existence are identical, and con.sequently He is not
included in any genus whatever. For the same
reason, it is impossible that God should be the formal
being of all things (esse formak orttnium), or, in other
words, that one and the same existence should be
common to Him and them (op. cit., I, 2.5, 26).
In the visible world there is a multitude of sub- stances numerically distinct. Each, moreover, has a specific nature which determines the mode of its activity and at the same time, through its activity, becomes, in some degree, manifest to us. Our think- ing does not constitute the substance; this exists in- dependently of us, and our thought at most acquires a knowledge of each substance by considering its manifestations. In this way we come to know both the nature of material things and the natiu-e of the spiritual substance within us, i. e. the soul. In both cases our knowledge may be imperfect, but we are not thereby justified in concluding that only the super- ficial appearances or phenomena are accessible to us, and that the inner substantial being, of matter or of mind, is unknowable.
Since the close of the Scholastic period, the idea of substance and the doctrines centring about it have undergone profound modifications which in turn have led to a complete reversal of the Scholastic teaching on vital questions in philosophy. Apart from the traditional concept formulated above, we must note especially Descartes' definition that substance is "a being that so exists as to require nothing else for its existence". This formula is unfortunate: it is false, for the idea of substance determines an essence which, if it exists, has its own existence not borrowed from an ulterior basis, and which is not a modification of some being that supports it. But this idea in no way ietermines either the manner in which actual exist- ence has been given to this e-ssence or the way in which it is preserved. The Cartesian definition, moreover, is dangerous; for it suggests that substance admits of no efficient cause, but exists in virtue of its own es- sence. Thus Spinoza, following in the footsteps of Descartes, declared that "substance is that which is conceived in itself and by itself", and thence deduced iiis pantheistic system according to which there is but Dne substance — i. e. God — all things else being only the modes or attributes of the Divine substance (see Pantheism). Leibniz's definition is also worthy of lote. He considers .sub.stance as "a being gifted with (he power of action". Substance certainly can act, since action follows being, and substance is being par excellence. But this property does not go to the basis 3f reality. In everj' finite substance the power to act is distinct from the substantial cs.sence; it is but a property of substance which can be defined only by its mode of existence.
II. — The most important question concerning sub- stance is that of its reality. In ancient days Heracli- tus, in modern times Hume, Locke, Mill, and Taine, and in our day Wundt, Mach, Paulsen, Ostwald,
Ribot, Jodl, Hoffding, Eisler, and several others deny
the reality of substance and consider the existence of
substance as an illusory postulate of naive minds.
The basis of this radical negation is an erroneous idea
of substance and accident. They hold that, apart
from the accidents, substance is nothing, a being
without qualities, operations, or end. This is quite
erroneous. The accidents cannot be separated thus
from the substance; they have their being only in the
substance; they are not the substance, but are by their
verj' nature modifications of the substance. "The
operations which these writers would thus attribute
to the accidents are really the operations of the sub-
stance, which exercises them through the accidents.
Finally, in attributing an independent existence to the
accidents, they simply transform them into substance,
thus establishing just what they intend to deny. It
can be said that whatever exists is either a substance
or in a substance.
The tendency of modern philosophy has been to regard substance simply as an idea which the mind indeed is constrained to form, but which either does not exist objectively or, if it does so e.xist, cannot be known. According to Locke (Essay ii, 23), "Not imagining how simple ideas can subsist by themselves, we accustom ourselves to suppose some substratum wherein they do subsist and from which they do re- sult; which therefore we call substance; so that if any one will examine himself concerning his notion of pure substance in general, he will find he has no other idea of it at all, but only a supposition of he knows not what support of such qualities, which are capable of producing simple ideas in us; which qualities are com- monly called accidents." He protests, however, that this statement refers only to the idea of substance, not to its being; and he claims that "we have as clear a notion of the substance of spirit as we have of body" (ibid.). Hume held that the idea of substance "is nothing but a collection of simple ideas that are united by the imagination and have a particular name as- signed to them, by which we are able to recall, either to ourselves or others, that collection" (Treatise, bk. I, pt. IV); and that the soul is "a bundle of con- ceptions in a perpetual flux and movement ".
For Kant substance is a category of thought which applies only to phenomena, i. e. it is the idea of some- thing that persists amid all changes. The substan- tiahty and immortahty of the soul cannot be proved by the pure reason, but are postulated by the moral law which pertains to the practical reason. J. S. Mill, after stating that "we may make propositions also respecting those hidden causes of phenomena which are named substances and attributes", goes on to say: "No assertion can be made, at least with a meaning, concerning those unknown and unknow- able entities, except in virtue of the phenomena by which alone they manifest themselvestoourfaculties" (Logic, bk. i, I, c. v): in other words, substance mani- fests itself through phenomena and yet is unknowable. Mill defines matter as "a permanent po.ssibility of sensation", so that no substantial bond is required for material objects; but for conscious states a tie is needed in which there is .something "real as the sen.sa- tions them.selves and not a mere product of the laws of thought" ("Examination", c. xi; cf. Appendix). Wundt, on the contrary, declares that the idea (hypo- thetical) of substance is neces.sary to connect the phenomena presented in outer exijerience, but that it is not applicable to our inner experience except for the p.sycho-physical processes (Logik, I, 484 sqq.). This is the basis of Actualism, which reduces the soul to a series of conscious states. Herbert Spencer's view is thus ex7)ressed: "Existence means nothing more than persistence; and hence, in mind, that which persists in spite of all changes, and maintains the unity of the aggregate in defiance of all attempts to divide it, is that of which existence in the full sense of the
