In another part of his argument, however, Mr. Sidgwick implies that I have no right to use those conceptions of objective existence by which this compromise is effected. Quoting sundry passages to show that while I hold the criticisms of the Idealist to be impossible without “tacitly or avowedly postulating an unknown something beyond con­scious­ness,” I yet admit that “our states of con­scious­ness are the only things we can know;” he goes on to argue that I am radically inconsistent, because, in interpreting the phenomena of con­scious­ness, I continually postulate, not an unknown something, but a something of which I speak in ordinary terms, as though its ascribed physical characters really exist as such, instead of being, as I admit they are, synthetic states of my con­scious­ness. His objection, if I understand it, is that for the purposes of Objective Psychology I apparently profess to know Matter and Motion in the ordinary realistic way; while, as a result of subjective analysis, I reach the conclusion that {247} it is impossible to have that knowledge of objective existence which Realism supposes we have. Doubtless there seems here to be what he calls “a fundamental incoherence.” But I think it exists, not between my two expositions, but between the two con­scious­nesses of subjective and objective existence, which we cannot suppress and yet cannot put into definite forms. The alleged incoherence I take to be but another name for the inscrutability of the relation between subjective feeling and its objective correlate which is not feeling—an inscrutability which meets us at the bottom of all our analyses. An exposition of this inscrutability I have elsewhere summed up thus:—

“See, then, our predicament. We can think of Matter only in terms of Mind. We can think of Mind only in terms of Matter. When we have pushed our explorations of the first to the uttermost limit, we are referred to the second for a final answer; and when we have got the final answer of the second, we are referred back to the first for an interpretation of it. We find the value of x in terms of y; then we find the value of y in terms of x; and so on we may continue for ever without coming nearer to a solution.”—Prin. of Psy. § 272.

Carrying a little further this simile, will, I think, show where lies the insuperable difficulty felt by Mr. Sidgwick. Taking x and y as the subjective and objective activities, unknown in their natures and known only as phenomenally manifested; and recognizing the fact that every state of con­scious­ness implies, immediately or remotely, the action of object on subject or subject on object, or both; we may say that every state of con­scious­ness will be symbolized by some modification of xy—the phenomenally-known product of the two unknown factors. In other words, xy′, x′y, x′y′, x″y′, x′y″, &c., &c., will represent all perceptions and thoughts. Suppose, now, that these are thoughts about the object; composing some hypothesis respecting its characters as analyzed by physicists. Clearly, all such thoughts, be they about shapes, resistances, momenta, molecules, molecular motions, or what not, will contain forms of the subjective activity x. Now let the thoughts {248} be concerning mental processes. It must similarly happen that some mode of the unknown objective activity y, will be in every case a component. Now suppose that the problem is the genesis of mental phenomena; and that, in the course of the inquiry, bodily organization and the functions of the nervous system are brought into the explanation. It will happen, as before, that these, considered as objective, have to be described and thought about in modes of xy. And when by the actions of such a nervous system, conceived objectively in modes of xy, and acted upon by physical forces which are conceived in other modes of xy, we endeavour to explain the genesis of sensations, perceptions, and ideas, which we can think of only in other modes of xy, we find that all our factors, and therefore all our in­ter­pre­ta­tions, contain the two unknown terms, and that no interpretation is imaginable that will not contain the two unknown terms.

What is the defence for this appar­ent­ly-circ­u­lar process? Simply that it is a process of establishing congruity among our symbols. It is finding a mode of so symbolizing the unknown activities, subjective and objective, and so operating with our symbols, that all our acts may be rightly guided—guided, that is, in such ways that we can anticipate, when, where, and in what quantity some one of our symbols, or some combination of our symbols, will be found. Mr. Sidgwick’s difficulty arises, I think, from having insufficiently borne in mind the statements made at the outset, in “The Data of Philosophy,” that such conceptions as “are vital, or cannot be separated from the rest without mental dissolution, must be assumed as true provisionally;” that “there is no mode of establishing the validity of any belief except that of showing its entire congruity with all other beliefs;” and that “Philosophy, compelled to make those fundamental assumptions without which thought is impossible, has to justify them by showing their congruity with all other dicta of con­scious­ness.” In {249} pursuance of this distinctly-avowed mode of procedure, I assume provisionally, an objective activity and a subjective activity, and certain general forms and modes (Space, Time, Matter, Motion, Force), which the subjective activity, operated on by the objective activity, ascribes to it, and which I suppose to correspond in some way to unknown forms and modes of the objective activity. These provisional assumptions, having been carried out to all their consequences, and these consequences proved to be congruous with one another and with the original assumptions, these original assumptions are justified. And if, finally, I assert, as I have repeatedly asserted, that the terms in which I express my assumptions and carry on my operations are but symbolic, and that all I have done is to show that by certain ways of symbolizing, perfect harmony results—invariable agreement between the symbols in which I frame my expectations, and the symbols which occur in experience—I cannot be blamed for incoherence. On the contrary, it seems to me that my method is the most coherent that can be devised. Lastly, should it be said that this regarding of everything constituting experience and thought as symbolic, has a very shadowy aspect; I reply that these which I speak of as symbols, are real relatively to our con­scious­ness; and are symbolic only in their relation to the Ultimate Reality.

That these explanations will make clear the coherence of views which before seemed “fundamentally incoherent,” I feel by no means certain; since, as I did not perceive the difficulties presented by the exposition as at first made, I may similarly fail to perceive the difficulties in this explanation. Originally, I had intended to complete the Principles of Psychology by a division showing how the results reached in the preceding divisions, physiological and psychological, analytic and synthetic, subjective and objective, harmonize with one another, and are but different aspects of the same aggregate of phenomena. But the work was already {250} bulky; and I concluded that this division might be dispensed with, because the congruities to be pointed out were sufficiently obvious. So little was I conscious of the alleged “inability to harmonize different lines of thought.” Mr. Sidgwick’s perplexities, however, show me that such an exposition of concords is needful.

I have reserved to the last, one of the first objections made to the me­ta­phys­i­co-the­o­lo­gi­cal doctrine set forth in First Principles, and implied in the several volumes that have succeeded it. It was urged by an able metaphysician, the Rev. James Martineau, in an essay entitled “Science, Nescience, and Faith;” and, effective against my argument as it stands, shows the need for some development of my argument. That Mr. Martineau’s criticism may be understood, I must quote the passages it concerns. Continuing the reasoning employed against Hamilton and Mansel, to show that our con­scious­ness of that which transcends knowledge is positive, and not, as they allege, negative, I have said:—

“Still more manifest will this truth become when it is observed that our conception of the Relative itself disappears, if our conception of the Absolute is a pure negation. It is admitted, or rather it is contended, by the writers I have quoted above, that contradictories can be known only in relation to each other—that Equality, for instance, is unthinkable apart from its correlative Inequality; and that thus the Relative can itself be conceived only by opposition to the Non-relative. It is also admitted, or rather contended, that the con­scious­ness of a relation implies a con­scious­ness of both the related members. If we are required to conceive the relation between the Relative and Non-relative without being conscious of both, ‘we are in fact’ (to quote the words of Mr. Mansel differently applied) ‘required to compare that of which we are conscious with that of which we are not conscious; the comparison itself being an act of con­scious­ness, and only possible through the con­scious­ness of both its objects.’ What, then, becomes of the assertion that, ‘the Absolute is conceived merely by a negation of conceivability,’ or as ‘the mere absence of the conditions under which con­scious­ness is possible?’ If the Non-relative or Absolute, is present in thought only as a mere negation, then the relation between it and the Relative becomes unthinkable, because one of the terms of the relation is absent from con­scious­ness. {251} And if this relation is unthinkable, then is the Relative itself unthinkable, for want of its antithesis: whence results the disappearance of all thought whatever.”—First Principles, § 26.

On this argument Mr. Martineau comments as follows; first re-stating it in other words:—

“Take away its antithetic term, and the relative, thrown into isolation, is set up as absolute, and disappears from thought. It is indispensable therefore to uphold the Absolute in existence, as condition of the relative sphere which constitutes our whole intellectual domain. Be it so: but when saved on this plea,—to preserve the balance and interdependence of two co-relatives,—the ‘Absolute’ is absolute no more; it is reduced to a term of relation: it loses therefore its exile from thought: its dis­qual­i­fi­ca­tion is cancelled: and the alleged nescience is discharged.

“So, the same law of thought which warrants the existence, dissolves the inscrutableness, of the Absolute.”—Essays, Philosophical and Theological pp. 186–7.

I admit this to be a telling rejoinder; and one which can be met only when the meanings of the words, as I have used them, are carefully discriminated, and the implications of the doctrine fully traced out. We will begin by clearing the ground of minor misconceptions.