or qualities,” since not flowing from the very being of substance, give no glimpse into its true nature. According to Leibniz, reality acts, and therefore is. Its being is conditioned upon its activity. It is not first there, and secondly acts; but its “being there” is its activity. Since its very substance is activity, it is impossible that it should not manifest its true nature. Its every activity is a revelation of itself. It cannot hide itself as a passive subsistence behind qualities or phenomena. It must break forth into them. On the other hand, since the qualities are not something which merely inhere in an underlying support, but are the various forms or modes of the activity which constitutes reality, they necessarily reveal it. They are its revelations. There is here no need to dwell further on the original dynamic nature of substance; what was said in the way of general exposition suffices. It is only in its relations to Locke’s view as just laid down that it now concerns us.
In the first place, Leibniz points out that qualities are “abstract,” while substance is “concrete.” The qualities, from the very fact that they have no self-subsistence, are only relations, while the substance, as that of which they are qualities, or from which they are abstractions, is concrete. It is, Leibniz says, to invert the true order to take qualities or abstract terms as the best known and most easily comprehended, and “concretes” as unknown, and as having the most difficulty about them. “It is abstractions which give birth to almost all our difficulties,” and Locke’s error here is that he begins with abstractions, and takes them to be most open to intelligence. Locke’s second error is separating so completely substance and attribute. “After having distinguished,” says Leibniz, “two things in substance, the attributes or predicates, and the common subject of these predicates, it is not to be wondered at that we cannot conceive anything in particular in the subject. This result is necessary, since we have separated all the attributes in which there is anything definite to be conceived. Hence to demand anything more than a mere unknown somewhat in the subject, is to contradict the supposition which was made in making the abstraction and in conceiving separately the subject and its qualities or accidents.” We are indeed ignorant of a subject from which abstraction has been made of all defining and characteristic qualities; “but this ignorance results from our demanding a sort of knowledge of which the object does not permit.” In short, it is a credit to our knowledge, not an aspersion upon it, that we cannot know that which is thoroughly unreal,—a substance deprived of all attributes. This is, indeed, a remark which is applicable to the supposed unknowableness of pure Being, or Absolute Being, when it is defined as the absence of all relations (as is done, for example, by Mr. Spencer to-day).
Closely connected with the notion of substance are the categories of identity and diversity. These relations are of course to Locke thoroughly external. It is “relation of time and place which always determines identity.” “That that had one beginning is the same thing; and that which had a different beginning in time and place from that, is not the same, but diverse.” It is therefore easy to discover the principle of individuation. It “is existence itself, which determines a being of any sort to a particular time and place, incommunicable to two beings of the same kind.” He applies this notion to organic being, including man, and to the personal identity of man. The identity of an organism, vegetable, brute, or human, is its continuous organization; “it is the participation of the same continued life, by constantly fleeting particles of matter in succession vitally united to the same organized body.” Personal identity is constituted by a similar continuity of consciousness. “It being the same consciousness that makes a man be himself to himself, personal identity depends on that only.” It “consists not in the identity of substance, but in the identity of consciousness.” It will be noticed that Locke uses the notion of identity which he has already established to explain organic and personal unity. It is the “same continued life,” “identity of consciousness,” that constitute them. We are, hence, introduced to no new principle. Identity is even in personality a matter of temporal and spatial relations.
In the general account of the system of Leibniz it was pointed out that it is characteristic of his thought to regard identity and distinction as internal principles, and as necessarily implied in each other. We need not go over that ground again, but simply see how he states his position with reference to what is quoted from Locke. These are his words: “Besides the difference of place and time there is always necessary an internal principle [or law] of distinction, so that while there may be several things of the same species, there are no two things exactly alike. Thus, although time and place (that is, relations to the external) aid us in distinguishing things, things do not cease to be distinguished in themselves. The essence of identity and diversity does not consist in time and place, although it is true that diversity of things is accompanied with that of time and place, since they carry along with them different impressions upon the thing;” that is, they expose the thing to different surroundings. But in reality “it is things which diversify times and places from one another, for in themselves these are perfectly similar, not being substances or complete realities.”
The principle of individuation follows, of course, from this. “If two individuals were perfectly similar and equal, that is, indistinguishable in themselves, there would be no principle of individuation; there would not be two individuals.” Thus Leibniz states his important principle of the “identity of indiscernibles,” the principle that where there is not some internal differentiating principle which specifies the existence in this or that definite way, there is no individual. Leibniz here states, in effect, the principle of organic unity, the notion that concrete unity is a unity of differences, not from them. It is the principle which allows him at once to accept and transform the thought of Spinoza that all qualification or determination is negation. Spinoza, in spite of his intellectual greatness, conceived of distinction or determination as external, and hence as external negation. But since ultimate reality admits of no external negation, it must be without distinction, an all-inclusive one. But to Leibniz the negation is internal; it is determination of its own being into the greatest possible riches. “Things that are conceived as absolutely uniform and containing no variety are pure abstractions.” “Things indistinguishable in themselves, and capable of being distinguished only by external characteristics without internal foundation, are contrary to the most important principles of reason. The truth is that every being is capable of change [or differentiation], and is itself actually changed in such a way that in itself it differs from every other.”
As to organic bodies, so far as they are bodies, or corporeal, they are one and identical only in appearance. “They are not the same an instant. . . . Bodies are in constant flux.” “They are like a river which is always changing its water, or like the ship of Theseus which the Athenians are constantly repairing.” Such unity as they really possess is like all unity,—ideal or spiritual. “They remain the same individual by virtue of that same soul or spirit which constitutes the ‘Ego’ in those individuals who think.” “Except for the soul, there is neither the same life nor any vital union.” As to personal identity, Leibniz distinguishes between “physical or real” identity and “moral.” In neither case, however, is it a unity which excludes plurality, an identity which does not comprehend diversity. “Every spirit has,” he says, “traces of all the impressions which it has ever experienced, and even presentiments of all that ever will happen. But these feelings are generally too minute to be distinguished and brought into consciousness, though they may be sometime developed. This continuity and connection of perceptions makes up the real identity of the individual, while apperceptions (that which is consciously apprehended of past experiences) constitute the moral identity and make manifest the real identity.” We have had occasion before to allude to the part played in the Leibnizian philosophy by “minute perceptions” or “unconscious ideas.” Of them he says, relative to the present point, that “insensible perceptions mark and even constitute the sameness of the individual, which is characterized by the residua preserved from its preceding states, as they form its connection with its present state.” If these connections are “apperceived” or brought into distinct consciousness, there is moral identity as well. As he expresses it in one place: “The self (soi) is real and physical identity; the appearance of self, accompanied with truth, is personal identity.” But the
