From these general characteristics of the physical order, as conceived by current science and current popular thought, arise the fundamental problems of Cosmology. We have to discuss—(1) the real nature of material existence, i.e. the ultimate significance of the distinction between the two orders, and the possibility of reducing them to one; (2) the justification for the distinction between mechanical and teleological processes, and for the conception of the physical order as rigidly conformable to uniform law; (3) the leading difficulties of the conceptions of time and space, and their bearing on the degree of reality to be ascribed to the physical order; (4) the philosophical implications of the application of the notion of evolution or development to the events of the physical order; (5) finally, we ought perhaps to deal very briefly and in a very elementary fashion with the problem of the real position of descriptive physical science as a whole in its relation to the rest of human knowledge.
Consult further:—F. H. Bradley, Appearance and Reality, chap. 26 (pp. 496-497, 1st ed.); H. Lotze, Outlines of Metaphysic, pp. 77-79; J. S. Mackenzie, Outlines of Metaphysics, bk. iii. chap. 2; J. Ward, Naturalism and Agnosticism. lect. 1.
[117]. I.e. existence of the same kind as that perceived by the senses, whether actually so perceived or not. In this sense the solid impenetrable extended atoms of Newton or Locke are “sensible” existence, inasmuch as their properties are the same in kind as certain perceptible properties of larger masses, though they are not themselves actually perceptible.
[118]. Of course the evolution must be mere subjective appearance if, as is sometimes assumed, the processes of the physical order are one and all purely mechanical. But this only shows that the current concept of the physical order is not free from inconsistencies.
CHAPTER II
THE PROBLEM OF MATTER
[§ 1.] The physical order, because dependent for its perceived qualities on the sense-organs of the percipient, must be the appearance of a more ultimate reality which is non-physical. [§ 2.] Berkeley’s criticism is fatal to the identification of this reality with “material substance.” The logical consequence of Berkeley’s doctrine that the esse of sensible things is percipi would be the subjectivist view that the physical order is only a complex of presentations. [§ 3.] But this is clearly not the case with that part of the physical order which consists of the bodies of my fellow-men. These have an existence, as centres of feeling, over and above their existence as presentations to my senses. [§ 4.] As the bodies of my fellows are connected in one system with the rest of the physical order, that order as a whole must have the same kind of reality which belongs to them. It must be the presentation to our sense of a system or complex of systems of experiencing subjects; the apparent absence of life and purpose from inorganic nature must be due to our inability to enter into a direct communion of interest with its members. [§ 5.] Some consequences of this view.
§ 1. In the preceding chapter we have very briefly indicated the nature of the steps by which reflective thought comes to distinguish sharply between a physical and a psychical order of existence. The physical order, when the concept has been brought into its complete shape by the inclusion of my own body and all its parts, is thought of as a system comprising all the bodies in the universe, that is, all the existences which are of the same kind as those which I directly perceive by means of the special senses.[[119]] Now, with regard to the whole physical order thus conceived two things seem fairly obvious upon the least reflection, that it does not depend for its existence upon the fact of my actually perceiving it, and that it does depend upon my perception for all the qualities and relations which I find in it. Its that appears independent of the percipient, but its what, on the other hand, essentially dependent on and relative to the structure of the perceiving organ. As we have already seen, the familiar experience of the variations in perception which accompany differences in the permanent structure or temporary functioning of the organs of sense led, very early in the history of Philosophy, to the recognition of this relativity, so far as the so-called “secondary” qualities, i.e. those which can only be perceived by one special sense-organ, are concerned. We have also seen sufficiently (in Bk. II. chap. 4) that the same consideration holds equally good of those “primary” qualities which are perceptible by more senses than one, and have probably for that reason been so often supposed to be unaffected by this relativity to a perceiving organ.
Without wasting the reader’s time by unnecessary repetition of our former reasoning, it may be worth while to point out here how this thorough-going relativity of the qualities of the physical order to a percipient organ leads directly to the indefinite regress, the apparently invariable consequence of all contradictions in Metaphysics, when we try to take those qualities as independently real. I perceive the properties of physical existence by special sense-organs, and the properties as perceived are conditioned by the structure of those organs. But each sense-organ is itself a member of the physical order, and as such is perceived by and dependent for its perceived qualities upon another organ. This second sense-organ in its turn is also a member of the physical order, and is perceived by a third, or by the first organ again. And there is no end to this mutual dependence. The physical order, as a whole, must be a “state” of my nervous system, which is itself a part of that order. We shall see more fully in our final Book, when we come to discuss the problem of Mind and Body, that this contradiction is an inevitable result of the inconsistency involved in the inclusion of my own body in the physical order, an inconsistency which is, in its turn, a necessary consequence of the hard-and-fast separation of the two orders of existence.[[120]]