Those who deny that it is possible to trace any progress in metaphysical controversy, and assert that such controversies neither are nor can be anything else than a process of beating the air, ought to compare the statements made of their respective views by Locke, Berkeley, Hume, and Mr. Mill on the one side, and by Reid, his later Scotch disciples, and Mr. Spencer on the other. Such a process would satisfy any fair and attentive student that the progress, though certainly exceedingly slow, is real, and that there is a prospect, though it may be a remote one, of an ultimate agreement upon the subjects which have perplexed mankind for so many centuries, There is no reason why this should not happen, and if it did, the effects on all speculation, and especially on morals, theology, and politics, would be enormous. For many centuries astronomy appeared a perfectly hopeless puzzle, yet at Inst the problem was solved; and almost every branch of natural science would furnish instances in which along period of guessing , and stumbling, sometimes of the most laborious kind, was at last succeeded by comparative light. Mr. Spencer differs from Mr. Mill fundamentally, but in many respects he approaches him so very closely, and the lines of thought. upon which their minds move are so obviously convergent, that we cannot but entertain a hope that, as far at least as they are concerned, an agreement upon the great subject which they discuss is not by any means out of the question.
It would be very difficult to state Mr. Spencer’s argument fully without reprinting his article, and we fear that we may do him some injustice by giving a free version of it in our own words. W's will, however, make the attempt, subject to the express warn' thus given. Mr. Spencer's main object is to show that Mr. M' fails in the attempt to construct a system of philosophy resting merely on experience, and admitting no proposition superior to, and independent of, experience. He admits, indeed, that most of the propositions which have hitherto been set up as first truths resting on some higher warrant than experience—such, we suppose, as the elementary propositions of arithmetic and geometry~—may be shown to rest on experience; but he maintains, by a variety of ingenious arguments. that the great doctrines of the existence of a self and a not—self—i.e. of an external world, and of that which perceives and deals with the external world—are “ dicta of consciousness,” or necessary truths which transcend experience, and can neither be proved y it nor spared from it. They are, in short, πον στώ; from which the world of speculation is to be moved. In order to bring out fully the grounds and the nature of this conclusion, he enters at considerable length, in different parts of his article, into the whole doctrine of necessary truths, and of inconceivability considered as the test of truth. In many parts of his writings Mr. Mill had objected to the views which e attributed to Mr. Spencer on these points. We think that Mr. Mill’s dissent applied to views very different from those which Mr. Spencer now maintains; but whether this arises from the fact that Mr. Mill originally misunderstood Mr. Spencer, or from the fact that Mr. Spencer himself has altered the views which he formerly held, is a question which we are neither inclined nor called upon to discuss.
As he puts the matter in the present article, Mr. Spencer considers that all our ideas are associated together more or less closely, and that some pairs are so closely associated together that wherever the one enters the other invariably and unconditionally follow. These last he describes as ultimate and absolute cohesions, which constitute the rules subject to which all thought and all reasoning is carried on. “No matter what he [the thinker] calls those indestructible relations, no matter what he supposes to .be their meanings, he is com lately fettered by them. Their indestructibility is the proof to him that his consciousness is imprisoned within them; and, supposing any of them to be in some .way destroyed, he perceives that indestructibility would still be the distinctive character of the bounds that remained—the test of those within which he must continue to think.” These ultimate “cohesions" or associations of ideas are what Mr. Spencer means by necessary truths: They are tested by making all the efforts to separate them which ingenuity can suggest. Try to think one .of the two thoughts without the other—for instance, try to think of motion without thinking of a moving bod —and if this turns out to be impossible, the connection between the two thoughts is necessary, and the associations belong to that class which “rules our thoughts whether we will or no." Of these indissoluble associations, one, and that the most general, important, and indisputable, is that which connects sensations with an external world producing them.
The inconceivability of a proposition appears to be much the same thin in Mr. Spencer's system as its necessity. He puts, for instance, the case of two straight lines of different lengths drawn on the same piece of paper close together, and he says that the proposition that the lines are unequal is a proposition of which the negation is inconceivable—that is to say, while we look at the lines the picture which they raise in the mind and the proposition that they are unequal cannot be separated. The one impression continually and unconditionally suggests the other. This inconceivability may be perceived directly and at once, as in the case of the lines, or it may be brought to our notice on reflection and comparison; as, for example, in the case of a proposition of Euclid, which, after comparison and examination, we perceive to be reducible to the form of a simple judgment as to the relations of certain lines which admit of being directly compared together by in ection, or what is equivalent to it.
So far is all this from being in any way contrary to the doctrines which Mr. Mill maintains in his criticisms on Sir William Hamilton—and which he implies, though he does not express them in so many words, in his other works—that they appear to come substantially to the same thing, so far at least as the theory of necessary truths and inconceivability is concerned. They are, indeed, expressed in a more complicated dialect than Mr. Mill would employ. For instance, to say that certain associations “rule” a man’s thoughts “whether he will or not," that his “consciousness is imprisoned within them," that “he submits to them because he has no choice,” and much other phraseology of the same kind, is by no means correct or free from objection. It is incorrect, because it implies the existence of free Will in a. sense in which neither Mr. Spencer nor Mr. Mill believes in an thing of the kind. A man’s thoughts, like his actions, might always be predicted if we knew all the antecedents; but it does not follow that men think under compulsion, i.e. under a sense of unpleasant restriction and with a conscious choice of the less of two evils; and this Seems to be implied by Mr. Spencer’s language. Probably, however, Mr. Spencer means no more than that certain thoughts are always, in fact, associated with certain others, and that all our thinking is performed by the help of these associations—the whole being ultimately reducible by a variety of devices to what he ca simple judgments of the mind on the information sup lied by the senses respecting (as he says) a world external to t e self in which the senses reside. Neither Mr. Mill nor any one else would object to any part of this statement, except that which asserts that t e senses inform us of an external world or of a self in which the senses reside. The real divergence between Mr. Spencer and Mr. Mill lies in the different views which they take about the old controversy raised by Berkeley, in which Mr. Mill has taken Berkeley’s art so vigorously. The principal interest of Mr. Spencer’s article lies in the arguments which he directs against this theory, and which, if we are not mistaken, are original. His proposition is that Berkeley's argument reposes on and is vitiated by a tacit petitio principii, and that it is impossible by any legitimate recess of reasoning to treat the proposition that there is an external world as an by hypothesis framed to account for facts, or to regard it many other light than that of a first truth formative of and not subjected to experience. The question is one of considerable curiosity, to say the least of it, and indirectly is of more real importance than is commonly ascribed to it; but we do not think that Mr. Spencer has succeeded any better than his predecessors in refuting a doctrine which one class of writers have always felt to be essential to their whole theory, and which, by a curious and as it were, hidden instinct, so many others have found themselves forced to try to invalidate.
Mr. Spencer’s argument is shortly expressed as follows:—“The conclusion reached is that Mind an Ideas are the only existences; yet the steps by which this conclusion is reached take for granted that external objects have just the kind of independent existence which is eventually denied.” “The word ‘impression’ cannot be translated in thought without assuming a thing impressing and a thing impressed.” In another part 0 the article he says that the existence of an external world cannot be viewed as an hypothesis confirmed by experience, because we have no other knowledge of it than through the facts for which it is intended to account. If a star were visible only through a certain glass, you could not appeal to the existence of the star to prove the excellence of the g ass, for the excellence of the glass must be assumed before the existence of the star could be alleged.
There is great ingenuity in these observations, but they appear to us altogether inconclusive and open to a very short answer, as follows. Mr. Spencer would, no doubt, admit that any relation which is perceived to exist between different states of consciousness may be supposed to exist between the mind and all states of consciousness. But the relation of externality and independence with respect to each other is perceived to exist between different states of consciousness. Therefore, a similar relation may be supposed to exist between the mind and all states of consciousness. That is, the mind can derive from mere experience—by the way of pure empiricism, as Mr. Spencer would call it-the hypothesis of an external world. It is true that this hypothesis cannot be confirmed by experience, inasmuch as it affects the interpretation of the whole of experience; but no one who believes in pure empiricism ever thought that it could be so confirmed. or could think so without giving up the characteristic art of his creed. His case is, that the existence of a world external to and independent of himself, in the same sense as that in which a boo is external to and independent of a table, whatever that sense may be, is a mere hypothesis, not admitting of proof, though plausible and natural. very phenomenon with which any one man is or can be acquainted is equally consistent with either of two theories —with the theory that there is, or with the theory that there is not, an assignable generic distinction between those parts of his consciousness which he calls sensation and those parts of his consciousness which he calls memory, imagination, volition, (be; and that this distinction, if it exists, consists in the fact that sensation is caused by external objects, whilst memory, imagination, volition—in a word, thought—are not so caused. As to the use of the word “impression” it is a matter of no importance. The idealist would say—I observe that there are relations between that state of consciousness which I call a seal and that other state of consciousness which I call wax, which supply a good metaphor for the illustration of the relation between my mind and all the states of consciousness of which it is susceptible. The question is not as to the manner in which I describe these relations, but as to the possibility of establishing the generic difference referred to above between different forms of consciousness.
These observations show, we think, how it is possible for a thorough-going idealist to arrive, b a legitimate process, at the hypothesis of an external world wit out any such petitio principii as is ascribed to him by Mr. Spencer. There is only one other set of thoughts for which it is unnecessary to account in an analogous manner, in order to do all that pure empiricism claims to do. This is the set of thoughts which are denoted by the pronoun “I." It may be said (as Descartes did say), Here at all events is a transcendent fact formative of experience, and not derived from it. Every thought implies a thinking subject. If you infer your own unity from experience, who and what is the You which receives the experience and draws the inference? The answer is, that though the word “I ” is one of the first which we learn, it is also, of all the words which we use, the one which we least understand. No one can doubt that experience alone informs us that the word includes the idea or image of hands, feet, heart, brain, a certain cast of features, &c.; and though no doubt it contains more than this, no one can exactly tell how much more it contains, or can doubt that the only way to find out is by observation and reflection, i.e. by experience. We are utterly in the dark as to the most important parts of our own nature, except in so far as experience has enlightened us on the subject; and the hardiest metaphysician would not deny that further experience alone can ' remove that darkness. Experience, then, it would seem, must have produced such knowledge as we have. It is no doubt true that, as matters now stand, the notion of a conscious subject appears to us logically to precede the acquisition of experience. But there is no necessary relation between the logical order -- the order in which we arrange our thoughts when we have them—and the order in which, in point of fact, we acquire the different elements of our knowledge. We see and feel certain things which we collectively call a tree. The word “tree” serves as a kind of box into which we can put all the information we subsequently collect about the thing; such, for instance, as the fact that it has sap, leaves, fruit, a sex, &c. ; and we are so constructed that all our thinking is done in this manner. But it does not follow that we knew all that is denoted by the word “tree " before we could have propositions about it. So the word “I” may well be no more than the name of our own body plus the various feelings mysteriously connected with it. Having got the word, we naturally enough think we have some definite (knowledge about it other than and beyond the knowledge which we derive from experience; but in principle this is just the same sort of error as it would be to suppose that we know something more about trees than experience has taught us, because the name tree stands ready, as it were, to connote as much knowledge as experience enables us to connect with it.
These considerations lead to the conclusion that pure empiricism can make out its case, and that it is possible to present every object whatever of human thought, to translate every word uttered or utterable by man into terms of experience. It is easy to understand the extraordinary reluctance which people show to admit this, even when they have gone as far in that direction as Mr. Herbert Spencer. The desire to get hold of some higher ground for belief than one’s own sensations, and some higher warrant for belief than the fact that the association of one idea with another does introduce this and not that conclusion into the mind, and that the conclusion so introduced harmonises with the testimony of the senses upon some definite point, is one of the strongest of intellectual appetites. It is, in philosophy, what an appetite for infallibility is in theology, and both the one and the other are no more than attempts to leap off your own shadow and to see through other men’s eyes. Such at least is the common motive. It would be impertinent to impute it to so careful and courageous a thinker as Mr. Spencer, and we must therefore conclude that he really is, as he says, unable to conceive the possibility of the Berkeleyan theory fully carried out—that in his mind the connection between sensation and external objects of sensation is indissoluble, and that, finding them indissoluble, he believes them.
It is always difficult to argue against such a statement, and there is really no reason to doubt it. Let us concede that Mr. Spencer cannot dissever the notion of sensation from that of an external object of sensation. Why should he doubt that others can, especially when they can describe the way in which they do it? Hallam, who had a strong taste for metaphysics, though he never, so far as we know, explicitly wrote on the subject, well remarked that most of the senses prove nothing at all as to an external world, and would not suggest it. Who would infer an external rose or an external sewer from their respective smells? Who would find it difficult to imagine that sounds were the growth of his own ears, and why, if so, should not sights and impressions on the sense of touch be attributed to similar causes? Take, again, the commonest of all common illustrations—the case of dreaming. What difference is there between dreaming and waking, except the greater vividness and consistency of our waking impressions? So simple and obvious—nay, so utterly trite—are these illustrations, that any one may make an intelligent boy of six years old not only understand them, but understand also that they are matters of no practical importance whatever, inasmuch as we despise dreams only by comparison with common life, and with a tacit admission that if they became as vivid, as consistent, and as long as our waking life, they would be of precisely the same importance, and would be realities in the very same sense of the word.
There is, however, another point of view perhaps a little less trite, though not equally convincing, from which the same subject may be viewed. A description of it may perhaps convince Mr. Spencer that there are people in the world who not only can disconnect the ideas which e considers to be indissolubly joined together, but who find a certain difficulty, at times at least, in connecting them. This point of view may be seized in a moment by any one who will reflect attentively on the commonest of phenomena—the progress of time. I walk down the street of a large town. I see a bridge, a river, a cathedral which has stood for many centuries, and hundreds of human beings going about their different tasks. As I walk I say, where are all the things and people which I saw not two minutes ago? They are pass and gone utterly and for ever, as much as the manufacturers of the flint instruments and the inhabitants of the lake cities. All of them have become portions and parcels of the buried past. What they were a minute ago is matter of memory, what they will be a minute hence is matter of conjecture. What then are they? What is the present? It is a picture on something which I call “I,” a camera obscura which, amongst other impressions, has one which it calls memory, and another which it calls anticipation. We are such stuff as dreams are made of, and our little life is rounded with a sleep. Surely it does not require a very lively imagination to realize the profound philosophical truth as well as the exquisite beauty of those celebrated words. As we watch the ever-rolling stream bear all its sons away, it is no difficult task to realize in t ought the possibility that we may be but the spectators of a great show presented on a little theatre, and that the unknown condition of thought which we describe as spirit may be the substance, and matter the accident of existence. Such feelings run, no doubt, into the sentimental vein; but the possibility of feeling them at all, the fact that they are not mere nonsense, but genuine reflections suggested to the mind by a positive fact—namely, the lapse of time—shows the possibility of separating the notions which Mr. Spencer considers inseparable.
Some apology is required for going at such length into such a very old controversy, but the fact is that the Berkeleyan theory, properly understood, is valuable principally for its negative results. It is the great theoretical bulwark against theoretical dogmatism, which is always on the watch to discover some new avenue by which it can erect a dominion over the progress of thought. Mr. Spencer is far enough from being a dogmatist in any sense of the word which could imply disapproval; but even he seems to feel a difficulty in doing justice to Berkeleyanism which is surprising in a man who thinks so clearly an fearlessly, and this induces us to go over the old familiar ground once more.
Saturday Review, August 12, 1865.