It may seem hardly necessary to add (what follows as a matter of course from [pp. 229-237], and what has been implied in our assertions all along) that nothing can be conceived twice over without being conceived in entirely different states of mind. Thus, my arm-chair is one of the things of which I have a conception; I knew it yesterday and recognized it when I looked at it. But if I think of it to-day as the same arm-chair which I looked at yesterday, it is obvious that the very conception of it as the same is an additional complication to the thought, whose inward constitution must alter in consequence. In short, it is logically impossible that the same thing should be known as the same by two successive copies of the same thought. As a matter of fact, the thoughts by which we know that we mean the same thing are apt to be very different indeed from each other. We think the thing now in one context, now in another; now in a definite image, now in a symbol. Sometimes our sense of its identity pertains to the mere fringe, sometimes it involves the nucleus, of our thought. We never can break the thought asunder and tell just which one of its bits is the part that lets us know which subject is referred to; but nevertheless we always do know which of all possible subjects we have in mind. Introspective psychology must here throw up the sponge; the fluctuations of subjective life are too exquisite to be arrested by its coarse means. It must confine itself to bearing witness to the fact that all sorts of different subjective states do form the vehicle by which the same is known; and it must contradict the opposite view.
The ordinary Psychology of 'ideas' constantly talks as if the vehicle of the same thing-known must be the same recurrent state of mind, and as if the having over again of the same 'idea' were not only a necessary but a sufficient condition for meaning the same thing twice. But this recurrence of the same idea would utterly defeat the existence of a repeated knowledge of anything. It would be a simple reversion into a pre-existent state, with nothing gained in the interval, and with complete unconsciousness of the state having existed before. Such is not the way in which we think. As a rule we are fully aware that we have thought before of the thing we think of now. The continuity and permanency of the topic is of the essence of our intellection. We recognize the old problem, and the old solutions; and we go on to alter and improve and substitute one predicate for another without ever letting the subject change.
This is what is meant when it is said that thinking consists in making judgments. A succession of judgments may all be about the same thing. The general practical postulate which encourages us to keep thinking at all is that by going on to do so we shall judge better of the same things than if we do not.[404] In the successive judgments, all sorts of new operations are performed on the things, and all sorts of new results brought out, without the sense of the main topic ever getting lost. At the outset, we merely have the topic; then we operate on it; and finally we have it again in a richer and truer way. A compound conception has been substituted for the simple one, but with full consciousness that both are of the Same.
The distinction between having and operating is as natural in the mental as in the material world. As our hands may hold a bit of wood and a knife, and yet do naught with either; so our mind may simply be aware of a thing's existence, and yet neither attend to it nor discriminate it, neither locate nor count nor compare nor like nor dislike nor deduce it, nor recognize it articulately as having been met with before. At the same time we know that, instead of staring at it in this entranced and senseless way, we may rally our activity in a moment, and locate, class, compare, count, and judge it. There is nothing involved in all this which we did not postulate at the very outset of our introspective work: realities, namely, extra mentem, thoughts, and possible relations of cognition between the two. The result of the thoughts' operating on the data given to sense is to transform the order in which experience comes into an entirely different order, that of the conceived world. There is no spot of light, for example, which I pick out and proceed to define as a pebble, which is not thereby torn from its mere time- and space-neighbors, and thought in conjunction with things physically parted from it by the width of nature. Compare the form in which facts appear in a text-book of physics, as logically subordinated laws, with that in which we naturally make their acquaintance. The conceptual scheme is a sort of sieve in which we try to gather up the world's contents. Most facts and relations fall through its meshes, being either too subtle or insignificant to be fixed in any conception. But whenever a physical reality is caught and identified as the same with something already conceived, it remains on the sieve, and all the predicates and relations of the conception with which it is identified become its predicates and relations too; it is subjected to the sieve's network, in other words. Thus comes to pass what Mr. Hodgson calls the translation of the perceptual into the conceptual order of the world.[405] In Chapter XXII we shall see how this translation always takes place for the sake of some subjective interest, and how the conception with which we handle a bit of sensible experience is really nothing but a teleological instrument. This whole function of conceiving, of fixing, and holding fast to meanings, has no significance apart from the fact that the conceiver is a creature with partial purposes and private ends. There remains, therefore, much more to be said about conception, but for the present this will suffice.
[386] There are two other 'principles of identity' in philosophy. The ontological one asserts that every real thing is what it is, that a is a, and b, b. The logical one says that what is once true of the subject of a judgment is always true of that subject. The ontological law is a tautological truism; the logical principle is already more, for it implies subjects unalterable by time. The psychological law also implies facts which might not be realized: there might be no succession of thoughts; or if there were, the later ones might not think of the earlier; or if they did, they might not recall the content thereof; or, recalling the content, they might not take it as 'the same' with anything else.
[387] In later chapters we shall see that determinate relations exist between the various data thus fixed upon by the mind. These are called a priori or axiomatic relations. Simple inspection of the data enables us to perceive them; and one inspection is as effective as a million for engendering in us the conviction that between those data that relation must always hold. To change the relation we should have to make the data different. 'The guarantee for the uniformity and adequacy' of the data can only be the mind's own power to fix upon any objective content, and to mean that content as often as it likes. This right of the mind to 'construct' permanent ideal objects for itself out of the data of experience seems, singularly enough, to be a stumbling-block to many. Professor Robertson in his clear and instructive article 'Axioms' in the Encyclopædia Britannica (9th edition) suggests that it may only be where movements enter into the constitution of the ideal object (as they do in geometrical figures) that we can "make the ultimate relations to be what for us they must be in all circumstances." He makes, it is true, a concession in favor of conceptions of number abstracted from "subjective occurrences succeeding each other in time" because these also are acts "of construction, dependent on the power we have of voluntarily determining the flow of subjective consciousness." "The content of passive sensation," on the other hand, "may indefinitely vary beyond any control of ours." What if it do vary, so long as we can continue to think of and mean the qualities it varied from? We can 'make' ideal objects for ourselves out of irrecoverable bits of passive experience quite as perfectly as out of easily repeatable active experiences. And when we have got our objects together and compared them, we do not make, but find, their relations.
[388] Cf. Hodgson, Time and Space, § 46. Lotze, Logic, § 11.
[389] "For though a man in a fever should from sugar have a bitter taste which at another time would produce a sweet one, yet the idea of bitter in that man's mind would be as distinct as if he had tasted only gall." (Locke's Essay bk. ii, chap. xi, § 3. Read the whole section!)