In a diagram like the accompanying b and β are, he argues, “mediately conjoined,” but a and α are “immediately co-adjacent.” Surely Dr. Stout forgets here that what can be intelligibly called “co-adjacent” are not lines but points or positions on the lines. And between any point in α and any point in a there are a plurality of intermediate positions, except for the special case of the extreme left point of a and the extreme right point of α. These, of course, coalesce in the single point M, and there is therefore no connection, mediate or immediate, left in this case.[[99]] The illustration, I think, may serve to reveal a serious discrepancy in Dr. Stout’s theory. He sees that relations presuppose a unity which is supra-relational, and which he calls “continuous,” on the ground of its supra-relational character. At the same time, to save the relational scheme from condemnation as leading to the endless regress, he has to turn this supra-relational unity itself into a sort of relation by calling it an immediate connection between adjacent terms, and thus ascribing to it the fundamental character of a discontinuous series. And I cannot help regarding this procedure as unconscious evidence to the truth of the principle, that what is not the truth about the whole of Reality is not ultimately the truth about any reality.
[73]. See the admirable account of the “natural conception” of the world in the final chapter of Avenarius, Der Menschliche Weltbegriff.
[74]. May I say here once for all, that when I oppose practice to intellectual speculation, I must be understood to mean by practice the alteration by myself of some datum of given existence. The activity of thought is thus for me not practical, precisely because the “truths” which I know or contemplate are not quà truths given existences operated upon and altered by the act of thinking.
[75]. Such a view of the mental life of the animal seems to have been actually held, for instance, by the late Professor T. H. Green. Yet see Green, Works, ii. 217.
[76]. Strictly speaking, the “solidity” or “impenetrability” of the ultimate particles of matter, which is with Locke and Newton one of the most prominent “primary” qualities, is not a “mathematical” property, but it still owes its inclusion in the list to the conviction of these philosophers that it is, like extension and form, fundamentally important for mathematical Physics. The explanation of the “secondary” qualities as subjective appears to go back to Democritus.
[77]. See the further elaboration of this analogy in Bk. III. chap. 3, § 2 ff.
[78]. Professor Sidgwick’s defence of the Lockian view (Philosophy: its Scope and Relations, p. 63 ff.) seems to me to ignore the point at issue. namely, that in any sense in which “secondary” qualities get their meaning from the content of sensation, primary qualities do the same. The whole point is that the sensation is not merely (as process) the occasion of our cognition of, e.g., hardness or softness, but also (as content) furnishes the very meaning of “hard” or “soft.” Cf. with what follows, Appearance and Reality, chap. 1.
[79]. The former alternative is that of scholasticism; in modern science the latter has been more or less consciously adopted by those thinkers who retain the notion of substances. The various qualities are on this view consequences of the relations in which each substance stands (a) to other interacting substances, and (b) in particular to the unknown substratum of our “consciousness.”
[80]. See chaps. 1 and 2 of bk. i. of his Metaphysic.