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LECTURE XI
APPLICATION OF THE LAWS OF PHYSICAL INQUIRY, TO THE PHILOSOPHY OF MIND, CONCLUDED. – ON CONSCIOUSNESS, AND ON MENTAL IDENTITY

In my last Lecture, Gentlemen, I considered, very fully, the two species of inquiry which the philosophy of mind admits in exact analogy to the two species of inquiry in the philosophy of matter, – the consideration of the mental phenomena, as successive, and therefore susceptible of arrangement in the order of their succession, as causes and effects, – and the consideration of them as complex, and therefore susceptible of analysis. I stated to you, that it was chiefly, if not wholly, in this latter view, as analytical, that I conceived the philosophy of mind to be a science of progressive discovery; though, as a science of analogy, it has not merely produced results, as astonishing, perhaps, in some cases, as any of those which the analysis of matter has exhibited, but presents still a field of inquiry, that may be considered as inexhaustible; since the mind cannot exist, without forming continually new combinations, that modify its subsequent affections, and vary, therefore, the products, which it is the labour of our intellectual analysis to reduce to their original elements.

What the chemist does, in matter, the intellectual analysis does in mind; the one distinguishing by a purely mental process of reflection, the elements of his complex feelings, as the other operates on his material compounds, by processes that are themselves material. Though the term analysis, however, may be used in reference to both processes, the mental, as well as the material, since the result of the process is virtually the same in both, it has been universally employed by philosophers, in the laws of the mind, without any accurate definition of the process; and I was careful, therefore, to explain to you the peculiar meaning, in which it is strictly to be understood in our science; that you might not extend to the mind and its affections, that essential divisibility, which is inconsistent with its very nature; and suppose that, when we speak of complex notions, and of thoughts and feelings that are united by association with other thoughts and feelings, we speak of a plurality of separable things. The complex mental phenomena, as I explained to you, are complex only in relation to our mode of conceiving them. They are, strictly and truly, as simple and indivisible states of a substance, which is necessarily in all its states simple and indivisible – the results, rather than the compounds, of former feelings, – to which, however, they seem to us, and from the very nature of the feelings themselves, cannot but seem to us, to bear the same species of relation, which a whole bears to the parts that compose it. The office of intellectual analysis, accordingly, in the mode in which I have explained it to you, has regard to this relation only. It is to trace the various affections or states of mind that have successively contributed, to form or to modify any peculiar sentiment or emotion, and to develope the elements, to which, after tracing this succession, the resulting sentiment or emotion is felt by us to bear virtually that relation of seeming comprehensiveness of which I spoke.

If, indeed, our perspicacity were so acute that we could distinguish immediately all the relations of our thoughts and passions, there could evidently be no discovery in the science of mind; but, in like manner, what discovery could there be, in the analysis of matter, if our senses were so quick and delicate, as to distinguish immediately all the elements of every compound? It is only slowly that we discover the composition of the masses without; and we have therefore a science of chemistry: – It is only slowly that we discover the relations of complex thought to thought; and we have therefore a science of mental analysis.

It is to the imperfection of our faculties, then, as forcing us to guess and explore what is half concealed from us, that we owe our laborious experiments and reasonings, and consequently all the science which is the result of these; and the proudest discoveries which we make may thus, in one point of view, whatever dignity they may give to a few moments of our life, be considered as proofs and memorials of our general weakness. If, in its relation to matter, philosophy be founded, in a very great degree, on the mere badness of our eyes, which prevents us from distinguishing accurately the minute changes that are constantly taking place in the bodies around us; we have seen, in like manner, that, in its relation to the mind, it is founded chiefly, or perhaps wholly, on the imperfection of our power of discriminating the elementary feelings, which compose our great complexities of thought and passion; the various relations of which are felt by us only on attentive reflection, and are, therefore, in progressive discovery, slowly added to relations that have before been traced. In both cases, the analysis, necessary for this purpose, is an operation of unquestionable difficulty. But it is surely not less so, in mind, than in matter; nor, when nature exhibits all her wonders to us, in one case, in objects that are separate from us, and foreign; and, in the other, in the intimate phenomena of our own consciousness, can we justly think, that it is of ourselves we know the most. On the contrary, strange as it may seem, it is of her distant operations, that our knowledge is least imperfect; and we have far less acquaintance with the sway which she exercises in our own mind, than with that by which she guides the course of the most remote planet, in spaces beyond us, which we rather calculate than conceive. The only science, which, by its simplicity and comprehensiveness, seems to have attained a maturity that leaves little for future inquiry, is not that which relates immediately to man himself, or to the properties of the bodies on his own planet, that are ever acting on his perceptive organs, and essential to his life and enjoyment; but that which relates to the immense system of the universe, to which the very orb, that supports all the multitudes of his race, is but an atom of dust, and to which himself, as an individual, is as nothing.

 
“Could he, whose rules the rapid comet bind,
Describe or fix one movement of his mind?
Who saw its fires here rise, and there descend,
Explain his own beginning or his end?
Go, wondrous creature! mount where Science guides,
Go, measure earth, weigh air, and state the tides;
Instruct the planets in what orbs to run,
Correct old Time, and regulate the Sun;
Go, soar with Plato to th' empyreal sphere,
To the first good, first perfect, and first fair;
Go, teach Eternal Wisdom how to rule —
Then drop into thyself, and be a fool!”⁴¹
 

That man should know so much of the universe, and so very little of himself, is, indeed, one of the circumstances, which, in the language of the same poet, most strongly characterize him, as the “jest and riddle” of that world, of which he is also no less truly “the glory.”

“That the intelligence of any being,” to use the words of D'Alembert, “should not pass beyond certain limits – that, in one species of beings, it should be more or less circumscribed, than in another – all this is not surprising, more than that a blade of grass should be less tall than a shrub; or a shrub than an oak. But that the same being should be at once arrested by the narrow circle which nature has traced around him, and yet constantly reminded, that, beyond these limits, there are objects which he is never to attain – that he should be able to reason, till he loses himself, on the existence and nature of these objects, though condemned to be eternally ignorant of them – that he should have too little sagacity to resolve an infinity of questions, which he has yet sagacity enough to make– that the principle within us, which thinks, should ask itself in vain, what it is which constitutes its thought, and that this thought, which sees so many things, so distant, should yet not be able to see itself, which is so near, —that self, which it is notwithstanding always striving to see and to know – these are contradictions, which, even in the very pride of our reasoning, cannot fail to surprise and confound us.”

All that remains for us, in that impossibility which nature has imposed on us of attaining a more intimate knowledge of the essence and constitution either of mind or of matter, is to attend to the phenomena which they present, analysing whatever is complex, and tracing the order of every sequence. By attentive reflection on the phenomena themselves, and on all the circumstances which precede or follow them, we shall be able to discover the relations which they mutually bear, and to distinguish their casual coincidence, or succession, from those invariable relations which nature has established among them as causes and effects. This, humble as it may seem, is, as I have said, the true philosophy of man; because it is all of which man is capable. To inquire, as may be thought, more deeply into the essences of things, or the nature of certain supposed bonds by which they are connected, is to show, not that we have advanced far in the progress of science, but that we have gone far astray; not that we know more than philosophers of humbler views and pretensions, but that we know less; since it proves that we are unacquainted with the limits within which nature has bounded our prospect, and have not attained that prime knowledge, which consists in knowing how little can be known.

If the philosophy, not of mind only, but of the universe, is to be found, as Hobbes has boldly said, within ourselves, – in the same manner as the perfect statue is to be found in the rude block of the quarry, when all the superfluous mass, that adheres to it, has been removed, – in no respect can it more justly be said to be in our own minds than in this, that it is only by knowing the true extent, and consequently the limits, of our intellectual powers, that we can form any rational system of philosophic investigation. Then, indeed, Philosophy may be truly said, in his strong figurative language, to be Human Reason herself, hovering over all created things, and proclaiming their order, their causes, and effects. “Philosophiam noli credere eam esse, per quam fiunt lapides philosophici, neque illam quam ostentant codices metaphysici; sed Rationem Humanum naturalem per omnes res creatas sedulo volitantem, et de earum ordine, causis, et effectibus, ea quæ vera sunt renuntiantem. Mentis ergo tuæ, et totius mundi filia philosophia in te ipso est; nondum fortasse figurata, sed genitori mundo qualis erat in principio informi similes. Faciendum ergo tibi est quod faciunt statuarii, qui materiam exculpentes supervacraeum, imaginem non faciunt sed inveniunt.”⁴²

After these remarks on physical inquiry in general, and its particular application to our own science, I trust that we shall now proceed to observe, and analyse, and arrange the mental phenomena, with clearer views, both of the materials on which we have to operate, and of the nature of the operations which we have to perform. We may consider the mind as now lying open before us, presenting to us all its phenomena, but presenting them in assemblages, which it is to be our labour to separate and arrange. In this separation and arrangement, there are difficulties, I confess, of no slight kind. But, I trust, that you have the spirit, which delights in overcoming difficulties, and which, even if its most strenuous exertions should fail, delights in the very strenuousness of the endeavour. In what admits our analysis, and in what transcends it, we shall always find much that is truly wonderful in itself, and deserving of our profoundest admiration; and, even in the obscurest parts of the great field of mind, though we may see only dimly, and must, therefore, be cautious in inquiring, and fearful of pronouncing, we may yet, perhaps, be opening paths that are to lead to discovery, and, in the very darkness of our search, may perceive some gleams of that light, which, though now only dawning upon us, is to brighten on the inquirers of other ages.

In proceeding to examine and compare the mental phenomena, the first circumstance that strikes us, prior to any attempt to arrange them in classes, is, that the mind which exhibits these is susceptible of a variety of feelings, every new feeling being a change of its state; and, indeed, it is by such changes alone that it manifests itself, either in our own consciousness, or in the actions of our fellow men. If it could exist only in one everlasting state, – such as now constitutes the feeling of any particular moment, – it is quite superfluous to say, that it could not reason upon this state, – for this very reasoning would itself imply the change, which is supposed to be impossible; and as little could this one unchanged and unchangeable feeling be an object of reasoning to others, even if there were any mode of its becoming manifest to them, which there evidently could not be. It is, perhaps, even not too extravagant an assertion of Hobbes, who supposes a mind so constituted as to perceive only one colour, and to perceive this constantly, and affirms, that, in that case, it would be absurd to say that it had any perception at all, being rather, as he expresses it, stupified than seeing. “Attonitum esse et fortasse aspectare eum, sed stupentem dicerem, videre non dicerem; adeo sentire semper idem, et non sentire ad idem recidunt.”

Mind, then, is capable of existing in various states; an enumeration of the leading classes of which, as I before remarked, is all that constitutes our definition of it. It is that, we say, which perceives, remembers, compares, grieves, rejoices, loves, hates; and though the terms, whatever they may be, that are used by us, in any such enumeration, may be few, we must not forget that the terms are mere inventions of our own for the purpose of classification, and, that each of them comprehends a variety of feelings, that are as truly different from each other, as the classes themselves are different. Perception is but a single word; yet, when we consider the number of objects that may act upon our organs of sense, and the number of ways in which their action, may be combined, so as to produce one compound effect, different from that which the same objects would produce separately, or in other forms of combination, how many are the feelings which this single word denotes! – so many, indeed, that no arithmetical computation is sufficient to measure their infinity.

Amid all this variety of feelings, with whatever rapidity the changes may succeed each other, and however opposite they may seem, we have still the most undoubting belief, that it is the same individual mind, which is thus affected in various ways. The pleasure, which is felt at one moment, has indeed little apparent relation to the pain that was perhaps felt a few moments before; and the knowledge of a subject, which we possess, after having reflected on it fully, has equally little resemblance to our state of doubt when we began to inquire, or the total ignorance and indifference which preceded the first doubt that we felt. It is the same individual mind, however, which, in all these instances, is pleased and pained, is ignorant, doubts, reflects, knows. There is something “changed in all, and yet in all the same,” which at once constitutes the thoughts and emotions of the hour, and yet outlives them, – something, which, from the temporary agitations of passion, rises, unaltered and everlasting, like the pyramid, that lifts still the same point to heaven, amid the sands and whirlwinds of the desert.

The consideration of the mind, as one substance, capable of existing in a variety of states, according as it is variously affected, and constituting, in these different states, all the complex phenomena of thought and feeling, necessarily involves the consideration of consciousness, and of personal identity. To the examination of these, accordingly, I now proceed, as essential to all the inquiries and speculations, in which we are afterwards to be engaged; since, whatever powers or susceptibilities we may consider as attributes of the mind, this consideration must always suppose the existence of certain phenomena, of which we are conscious, and the identity of the sentient or thinking principle, in which that consciousness resides, and to which all the varieties of those ever-changing feelings, which form the subjects of our inquiry, are collectively to be referred.

Our first inquiry, then, is into the nature of

CONSCIOUSNESS

In the systems of philosophy, which have been most generally prevalent, especially in this part of the Island, consciousness has always been classed as one of the intellectual powers of the mind, differing from its other powers, as these mutually differ from each other. It is accordingly ranked by Dr Reid, as separate and distinct, in his Catalogue of the Intellectual Powers; and he says of it, that “it is an operation of the understanding of its own kind, and cannot be logically defined. The objects of it are our present pains, our pleasures, our hopes, our fears, our desires, our doubts, our thoughts of every kind, – in a word, all the passions, and all the actions and operations of our own minds, while they are present.” And in various parts of his works, which it would be needless to quote, he alludes to its radical difference from the other powers of the mind, as if it were a point on which there could be no question. To me, however, I must confess, it appears that this attempt to double, as it were, our various feelings, by making them not to constitute our consciousness, but to be the objects of it, as of a distinct intellectual power, is not a faithful statement of the phenomena of the mind, but is founded, partly on a confusion of thought, and still more on a confusion of language. Sensation is not the object of consciousness different from itself, but a particular sensation is the consciousness of the moment; as a particular hope, or fear, or grief, or resentment, or simple remembrance, may be the actual consciousness of the next moment. In short, if the mind of man, and all the changes which take place in it, from the first feeling with which life commenced, to the last with which it closes, could be made visible to any other thinking being, a certain series of feelings alone, that is to say, a certain number of successive states of the mind, would be distinguishable in it, forming, indeed, a variety of sensations, and thoughts, and passions, as momentary states of the mind, but all of them existing individually, and successively to each other. To suppose the mind to exist in two different states, in the same moment, is a manifest absurdity. To the whole series of states of the mind, then, whatever the individual momentary successive states may be, I give the name of our consciousness, – using that term, not to express any new state additional to the whole series, (for to that, which is already the whole nothing can be added, and the mind, as I have already said, cannot be conceived to exist at once in two different states,) but merely as a short mode of expressing the wide variety of our feelings; in the same manner, as I use any other generic word, for expressing briefly the individual varieties comprehended under it. There are not sensations, thoughts, passions, and also consciousness, any more than there is quadruped or animal, as a separate being, to be added to the wolves, tigers, elephants, and other living creatures, which I include under those terms.

The fallacy of conceiving consciousness to be something different from the feeling, which is said to be its object, has arisen, in a great measure, from the use of the personal pronoun I, which the conviction of our identity, during the various feelings, or temporary consciousnesses of different moments, has led us to employ, as significant of our permanent self, of that being, which is conscious, and variously conscious, and which continues, after these feelings have ceased, to be the subject of other consciousness, as transient as the former. I am conscious of a certain feeling, really means, however, no more than this – I feel in a certain manner, or, in other words, my mind exists in that state which constitutes a certain feeling; the mere existence of that feeling, and not any additional and distinguishable feeling that is to be termed consciousness, being all which is essential to the state of my mind, at the particular moment of sensation; for a pleasure, or pain, of which we are not conscious, is a pleasure or pain, that, in reference to us at least, has no existence. But when we say, I am conscious of a particular feeling, in the usual paraphrastic phraseology of our language, which has no mode of expressing, in a single word, the mere existence of a feeling, we are apt, from a prejudice of grammar, to separate the sentient I and the feeling as different, – not different, as they really are, merely in this respect, that the feeling is one momentary and changeable state of the permanent substance I, that is, capable of existing also, at other moments, in other states, – but so radically different, as to justify our classing the feeling, in the relation of an object, to that sentient principle which we call I, – and an object to it, not in retrospect only, as when the feeling is remembered, or when it is viewed in relation to other remembered feelings, – but in the very moment of the primary sensation itself; as if there could truly be two distinct states of the same mind, at that same moment, one of which states is to be termed sensation, and the other different state of the same mind to be termed consciousness.

To estimate more accurately the effect, which this reference to self produces, let us imagine a human being to be born with his faculties perfect as in mature life, and let us suppose a sensation to arise for the first time in his mind. For the sake of greater simplicity, let us suppose the sensation to be of a kind as little complex as possible; such for example, as that which the fragrance of a rose excites. If, immediately after this first sensation, we imagine the sentient principle to be extinguished, what are we to call that feeling, which filled and constituted the brief moment of life? It was a simple sensation, and nothing more; and if only we say, that the sensation has existed, – whether we say, or do not say, that the mind was conscious of the sensation, – we shall convey precisely the same meaning; the consciousness of the sensation being, in that case, only a tautological expression of the sensation itself. There will be, in this first momentary state, no separation of self and the sensation, – no little proposition formed in the mind, I feel, or I am conscious of a feeling; but the feeling and the sentient I will, for the moment, be the same. It is this simple feeling, and this alone, which is the whole consciousness of the first moment; and no reference can be made of this to a self, which is independent of the temporary consciousness; because the knowledge of self, as distinct from the particular feeling, implies the remembrance of former feelings, – of feelings, which, together with the present, we ascribe to one thinking principle, – recognizing the principle, the self, the one, as the same, amid all its transient diversities of consciousness.

Let us now, then, instead of supposing life, as in the former case, to be extinguished immediately after the first sensation, suppose another sensation to be excited, as for instance that which is produced by the sound of a flute. The mind either will be completely absorbed in this new sensation, without any subsequent remembrance, – in which case the consciousness of the sensation, as in the case of the fragrance that preceded it, will be only another more paraphrastic expression of the simple sensation – or the remembrance of the former feeling will arise. If the remembrance of the former feeling arise, and the two different feelings be considered by the mind at once, it will now, by that irresistible law of our nature, which impresses us with the conviction of our identity, conceive the two sensations, which it recognizes as different in themselves, to have yet belonged to the same being, – that being, to which, when it has the use of language, it gives the name of self, and in relation to which it speaks, as often as it uses the pronoun I. – The notion of self, as the lasting subject of successive transient feelings, being now, and not till now, acquired, through the remembrance of former sensations or temporary diversities of consciousness, the mind will often again, when other new sensations may have arisen, go through a similar process, being not merely affected with the particular momentary sensation, but remembering other prior feelings, and identifying it with them, in the general designation of self. In these circumstances the memory of the past will often mingle with and modify the present; and now indeed, to form the verbal proposition, I am conscious of a particular sensation, – since the very word I implies that this remembrance and identification has taken place, – may be allowed to express something more than the mere existence of the momentary sensation: for it expresses also that the mind, which now exists in the state of this particular sensation, has formerly existed in a different state. There is a remembrance of former feelings, and a belief that the present and the past have been states of one substance. But this belief, or in other words, this remembrance of former feelings, is so far from being essential to every thought or sensation, that innumerable feelings every moment arise, without any such identification with the past. They are felt, however, for this is necessarily implied in their existence; but they exist, as transient thoughts or sensations only, and the consciousness, which we have of them, in these circumstances, is nothing more, than the thoughts or sensations themselves, which could not be thoughts or sensations if they were not felt.

In the greater number of our successions of momentary feelings, then, when no reference is made to former states of the mind, the consciousness is obviously nothing more than the simple momentary feeling itself as it begins and ceases; and when there is a reference to former states of the mind, we discover on analysis only a remembrance, like all our other remembrances, and a feeling of common relation of the past and the present affection of the mind to one permanent subject. It is the belief of our continued identity which involves this particular feeling of relation of past and present feelings; and consciousness, in this sense of the term, is only a word expressive of that belief.

That the fragrance of a rose, the sound of a flute, and in general all the other objects of sense, might have excited precisely the same immediate sensations as at present, Doctor Reid admits, though the belief of our personal identity had not been impressed upon us; for he ascribes this belief to an instinctive principle only, and acknowledges, that there is nothing in our sensations themselves, from which any such inference could be drawn by reason. If, then, this instinctive belief of identity had not been, as at present, a natural law of human thought, – operating irresistibly on the remembrance of our different feelings, we should have had no notion of self, of me, the sentient and thinking being, who exists at the present moment, and who existed before the present moment: – and what, then, would have been the consciousness, accompanying, and different from, our sensations, when they merely flashed along the mind and vanished? The most zealous defender of consciousness, as a separate intellectual power, must surely admit, that, in such circumstances, it would have been nothing more than sensation itself. It is the belief of our identity only, which gives us the notion of self, as the subject of various feelings, and it is the notion of self, as the subject of various former feelings, which leads us to regard the consciousness of the moment, as different from the sensation of the moment; because it suggests to us those former feelings, which truly were different from it, or at least that subject mind, which unquestionably existed before the present sensation.

If it be said, that the faculty of consciousness is nothing more than this reference to the past, and consequent belief of identity, we may, in that case, very safely admit its existence; though the classification of it, as a peculiar intellectual power, would in that case be a most singular anomaly in arrangement, and would involve a very absurd, or at least a very awkward use of a term. To assert this signification of it, however, would be to admit everything for which I have contended. But it certainly is not the sense, which has been attached to it by philosophers; and indeed, in this sense, consciousness, instead of having for its objects, as Doctor Reid says, all “our present pains, our pleasures, our hopes, our fears, our desires, our doubts, our thoughts of every kind; in a word, all the passions, and all the actions and operations of our own mind, while they are present,” would be limited to the comparatively few, of which the consideration of our personal identity forms a part. In far the greater number of our feelings, as I have already said, the sensation dies away, almost in the moment, – not indeed, without being enjoyed or suffered, but without any reference to self, as the subject of various feelings, or remembrance of any prior state of mind, as distinct from the present. The belief of our identity, is surely not the only belief that arises from an instinctive principle; and if its existence entitle us, in our systematic arrangements, to the possession of a new intellectual power, every other belief that arises instinctively from a principle of our constitution, must give us a similar title to enlarge the catalogue of our faculties. The never-failing and instant faith, by which we expect, without the slightest doubt of the similarity of the future, that events will continue to follow each other, in the same order as at present, – that bodies will fall to the ground, fire burn, food satisfy the craving of our appetite – that immediate intuitive principle of belief, on which all our foresight depends, and according to which we regulate our whole conduct in providing for the future, – should certainly, in that case, be ascribed by us to some peculiar intellectual power, for which it would be easy to invent a name. It is not, by any inference of our reason, we believe, that the sound of a flute which preceded the fragrance of a rose, and the fragrance of a rose which followed the sound of a flute, excited sensations that were states of the same identical mind; for there is nothing, in either of the separate sensations, or in both together, from which such an inference can be drawn; and yet, notwithstanding the impossibility of inferring it, we believe this, at least as strongly, as we believe any of the conclusions of our reasoning. In like manner, it is not by any inference of reason we believe, that fire will warm us to-morrow, as it has warmed us to-day; for there is nothing, in the fire of to-day, or in the sensation of warmth, considered as a mere sequence of it, from which the succession of a similar sensation to the fire of to-morrow can be inferred; yet we also rely on this future sequence, at least as strongly, as we believe any of the conclusions of our reasoning. In both cases the parallel is complete; and in both, the evidence of a particular intellectual faculty, must consequently be alike, – or in neither is there sufficient evidence of such a power.