Lectures on the Philosophy of the Human Mind (Vol. 1 of 3)

by Thomas Brown

Footnotes

[44] Mart. Scrib. chap. vii.—Pope's Works, edit. 1757, v. vii. p. 82–84.

[45] Essays on the Intellectual Powers, Essay III. chap. iv.—v. 1. p. 341. Edit. Ed. 1808.

[46] Monsieur Des Cartes. Shaftesb.

[47] Shaftesbury's Characteristics, vol. iii. p. 172–174. Edit. 1745.

[48] Pope's Essay on Man, Ep. II. v. 275–282.

[LECTURE XIII.]

ON THE DIRECT EVIDENCE OF MENTAL IDENTITY; AND OBJECTIONS ANSWERED.

My last Lecture, Gentlemen, was employed in considering the great question of the Identity of the Mind, as one and permanent, amid all the infinite variety of our feelings; and particularly, in stating the two most forcible objections, which I can imagine to be urged against this identity,—one founded on the striking contrasts, intellectual and moral, which the same mind exhibits in different periods of life, and in different circumstances of fortune,—the other, more abstract, and, therefore, less obvious, but not less forcible, founded on the mere diversity of our temporary feelings, as itself inconsistent with identity, at least with that strict and absolute identity, to which, as in the case of the mind, nothing can have been added,—from which nothing can have been taken away,—and which, by its very nature, as simple and indivisible, must have been incapable of any elementary change.

Since the exposure of the fallacy, on which these objections are founded, would, however, afford only a sort of negative evidence of that great truth which they oppose, it will be of advantage, before entering on an examination of the objections themselves, to state, in the first place, the nature of that positive evidence, which does not, indeed, lead us to the belief of the unity and permanence of our spiritual being, by that slow process which is denominated reasoning, but constitutes to us, primarily and directly, an impossibility of disbelieving it. I do this the more readily, from the opportunity which it gives of making you acquainted with the paramount importance of those principles of intuitive belief, which are essential to philosophy in all its forms, as they are physically essential, indeed, to the very preservation of our animal existence; and which the rash and unphilosophic extension of them by one class of philosophers, and the equally unphilosophic misapprehension of them by other writers who controverted them, have rendered more necessary, than it would otherwise have been, to state to you with precision.

Of these first truths, as they have been termed, the subject, which we are at present considering, affords one of the most striking examples. The belief of our identity is not the result of any series of propositions, but arises immediately, in certain circumstances, from a principle of thought, as essential to the very nature of the mind, as its powers of perception or memory, or as the power of reasoning itself, on the essential validity of which, and consequently on the intuitive belief of some first truth on which it is founded, every objection to the force of these very truths themselves must ultimately rest. To object is to argue; and to argue is to assert the validity of argument, and, therefore, of the primary evidence, from which the evidence of each succeeding proposition of the argument flows. To object to the authority of such primary intuitive belief, would thus be to reason against reason,—to affirm and deny at the same moment,—and to own that the very arguments which we urge are unworthy of being received and credited.

As the nature of the process of reasoning has not yet come under our review, it may not at first appear to you, how essential the truths of intuition are to those very truths which are usually opposed to them. But that they are thus essential, a very little attention will be sufficient to show you.

All belief, it is evident, must be either direct or indirect. It is direct, when a proposition, without regard to any former proposition expressed or understood, is admitted as soon as it is expressed in words, or as soon as it rises silently in the mind. Such are all the order of truths, which have been denominated, on this account, first truths. The belief is indirect, when the force of the proposition, to which assent is given, is admitted only in consequence of the previous admission of some former proposition, with which it is felt to be intimately connected; and the statement in words, or the internal developement of these relative propositions in the order in which their relation to the primary proposition is felt, is all that constitutes reasoning. The indirect belief which attends the result of reasoning, even in the proudest demonstration, is thus only another form of some first truth, which was believed directly and independently of reasoning; and, without this primary intuitive assent, the demonstration itself, in all its beautiful precision and regularity, would be as powerless and futile as the most incoherent verbal wrangling.

Without some principles of immediate belief, then, it is manifest, that we could have no belief whatever; for we believe one proposition, because we discover its relation to some other proposition, which is itself, perhaps, related, in like manner, to some other proposition formerly admitted, but which, carried back as far as it may, through the longest series of ratiocination, must ultimately come to some primary proposition, which we admit from the evidence contained in itself, or, to speak more accurately, which we believe from the mere impossibility of disbelieving it. All reasoning, then, the most sceptical, be it remarked, as well as the most dogmatical, must proceed on some principles, which are taken for granted, not because we infer them by logical deduction, for this very inference must then itself be founded on some other principle assumed without proof; but because the admission of these first principles is a necessary part of our intellectual constitution. The ridicule, therefore, with which Dr Priestley and some other English metaphysicians, were disposed to regard the decision of philosophical questions, on certain ultimate principles of common sense, was surely, at least in its wide degree of extension, misplaced; though the phrase common sense, it will be admitted, was not the happiest that could have been chosen. The controversy, indeed, was truly a verbal and insignificant one, unless as far as it had reference to the unnecessary multiplication of these principles, by the philosophers of this part of the island whom Dr Priestley opposed; since, if traced to their ultimate evidence, it could have been only from some one or more of the principles of common sense, at least from those primary universal intuitions of direct belief, which were all that Dr Reid and his friends meant to denote by the term, that the very reasonings employed against them derived even the slightest semblance of force. An argument that rejects not the phrase common sense only, which is of little consequence, but also what the phrase was intended, by its authors, to imply, is an argument confessedly founded upon nothing; which, therefore, as wholly unfounded, requires no answer, and which, at any rate, it would be vain to attempt to answer, because the answer, if it proceed on any ground whatever, must begin with assuming what the argument rejects, as inadmissible.

All reasoning, then, I repeat, whether sceptical or dogmatical, must take for granted, as its primary evidence, the truth of certain propositions, admitted intuitively, and independently of the reasoning, which follows, but cannot precede, the perception of their truth; and hence, as we cannot suppose that the subsequent ratiocination, though it may afford room for errors in the process, can at all add evidence to these primary truths; which, as directly believed, are themselves the ultimate evidence of each successive proposition, down to the last result of the longest argument; we must admit that our identity, if it be felt by us intuitively, and felt universally, immediately, irresistibly, is founded on the very same authority as the most exact logical demonstration, with this additional advantage, that it is not subject to those possibilities of error in the steps of the demonstration, from which no long series of reasoning can be exempt.

So little accustomed are we, however, to think of this primary fundamental evidence of every reasoning, while we give our whole attention to the consecutive propositions which derive from it their force, that we learn, in this manner, to consider truth and reasoning as necessarily connected, and to regard the assertion of truths that do not flow from reasoning, as the assertion of something which it would be equally unworthy of philosophy to assert or to admit; though every assertion and every admission, which the profoundest reasoner can make, must, as we have seen, involve the direct or indirect statement of some truth of this kind. Nor is it wonderful that we should thus think more of the reasoning itself, than of the foundation of the reasoning; since the first truths, which give force to reasoning but require no reasoning to establish them, must necessarily be of a kind which all admit, and which, therefore, as always believed by us, and undisputed by others, have excited no interest in discussion, and have never seemed to add to our stock of knowledge, like the results of reasoning, which have added to it truth after truth. Yet that they are thus uninteresting to us, is the effect only of their primary, and universal, and permanent force. They are the only truths, in short, which every one admits; and they seem to us unworthy of being maintained as truths, merely because they are the only truths which are so irresistible in evidence, as to preclude the possibility of a denial.

It is not as the primary evidence of all our processes of reasoning, however, that they are chiefly valuable. Every action of our lives is an exemplification of some one or other of these truths, as practically felt by us. Why do we believe, that what we remember truly took place, and that the course of nature will be in future such as we have already observed it? Without the belief of these physical truths, we could not exist a day, and yet there is no reasoning from which they can be inferred.

These principles of intuitive belief, so necessary for our very existence, and too important, therefore, to be left to the casual discovery of reason, are, as it were, an internal never-ceasing voice from the Creator and Preserver of our being. The reasonings of men, admitted by some, and denied by others, have over us but a feeble power, which resembles the general frailty of man himself. These internal revelations from on high, however, are omnipotent like their Author. It is impossible for us to doubt them, because to disbelieve them would be to deny what our very constitution was formed to admit. Even the Atheist himself, therefore, if, indeed, there be one who truly rejects a Creator and Ruler of the universe, is thus every moment in which he adapts his conduct implicitly, and without reasoning, to these directions of the Wisdom that formed him, obeying, with most exact subserviency, that very Voice which he is professing to question or to deride.

That the assertion of principles of intuitive belief, independent of reasoning, may be carried to an extravagant and ridiculous length,—as, indeed, seems to me to have been the case in the works of Dr Reid, and some other Scotch philosophers, his contemporaries and friends,—no one can deny; nor that the unnecessary multiplication of these would be in the highest degree injurious to sound philosophy,—both as leading us to form false views of the nature of the mind, in ascribing to it principles which are no part of its constitution, and, still more, as checking the general vigour of our philosophic inquiry, by seducing us into the habit of acquiescing too soon, in the easy and indolent faith, that it is unnecessary for us to proceed farther, as if we had already advanced as far as our faculties permit. It is the more unfortunate, because our very avidity for knowledge, which is only another name for that philosophic curiosity in which inquiry originates, is itself favourable to this too easy acquiescence; tending, consequently, by a sort of double influence, to repress the very speculation to which it gave rise. This it does, by rendering the suspense of ungratified curiosity so painful to us, as to resemble, in a very great degree, the uneasiness which we feel from the ungratified cravings of bodily appetite. We more readily, therefore, yield to the illusion which seems to remove this suspense: and are happy to think, however falsely, that we have now completed our inquiry, and that, without attempting any more elementary analysis, we may content ourselves with simply classing the results which we have already obtained. Though there is no human being who must not have felt doubts on some point or other, it is not every one who knows how to doubt. To the perfection of a doubt, indeed, it is essential,—if I may apply to it what rhetoricians say of an epic or dramatic narrative,—that it should have a beginning, a middle, and in many cases, too, though not in all, an end. The middle is a very easy matter; the great difficulty relates to the beginning and the end, and to the end not less than the beginning. We err equally, when the doubt ceases too soon, and when it does not cease where it ought to cease. There is a scepticism as different from the true spirit of philosophy, as the most contented ignorance, that has never questioned a single prejudice; a scepticism, which, instead of seeking to distinguish truth from falsehood, professes to deny altogether the competency of our faculties as to making such a distinction in any case, and to which any proposition, therefore, is as likely as its opposite. With this wild half reasoning extravagance, which is ignorant whether it affirms or denies, and which does not even know certainly that it has any uncertainty at all, it would be manifestly absurd to reason; and we may even truly say of it, notwithstanding the high character of perfect doubting which it affects, that it does not know how to doubt more than the all-credulous imbecility which it despises and derides; because it does not know in what circumstances doubt is legitimate, and in what circumstances it should cease. But, at the same time, he also, it may be said, does not know how to doubt, who is completely satisfied with the result of an inquiry which he is capable of prosecuting still further,—even though it were only by the addition of a single step to the thousand which he may already have made. Truth is the last link of many long chains; the first links of all of which, Nature has placed in our hands. When we have fairly arrived at the last, and feel completely that there is no link beyond, it would be manifestly absurd to suppose, that we can still proceed further;—but if we stop before we have arrived at the last, maintaining, without stretching out our hand to make the experiment, that there cannot be yet another link after that which we have reached, it matters not how far we may have advanced. Truth is still beyond us—to be grasped only by an arm more vigorous and persevering.

If, instead of maintaining boldly, that we have reached the last link of the chain, we content ourselves with affirming, that we have reached the last which human effort can reach, we must beware that we do not measure the incapacity of the whole race of mankind by our own individual inability, or, which is far from improbable, that we do not mistake for inability, even in ourselves, what is only the irksomeness of long continued exertion. Our power is often much greater than we are willing to believe; and in many cases, as La Rochefoucault very justly says, it is only to excuse to ourselves our own indolence that we talk of things as impossible. “Non putant fieri,” says Seneca, speaking of persons of this character, “quicquid facere non possunt. Ex infirmitate sua ferunt sententiam.”—“Scis quare non possumus ista? Quia nos posse non credimus.”—“Magno animo de rebus magnis judicandum est; alioqui videbitur illarum vitium esse quod nostrum est.”

Much evil, then, it must be admitted, would arise in the Philosophy of Mind from a disposition to acquiesce too soon in instinctive principles of belief. But though these may be, and have been, multiplied unnecessarily, and beyond the truth of nature, it is not less certain, that of our mental nature such principles are truly a part. We should, indeed, draw monsters, not men, if we were to represent the human head and trunk with a double proportion of arms and legs; but we should also give an unfaithful portraiture of the human figure, and should draw monsters, not men, if we were to represent them with but one arm and leg, or with no arm or leg at all. In like manner, to suppose the mind endowed with more principles of intuition than belong to it, would be to imagine a species of mental monster. But it would not less be a mental monster, if we were to attempt to strip it of the principles which it truly possesses.

In contending, then, for the authority of certain first principles of belief, such as that on which I conceive the conviction of our identity to be founded, I am sufficiently aware, in how many instances, reference to these has been rashly made by philosophers; when a deeper and more minute analysis would have shewn, that the supposed first principles were not elementary laws of thought, but were resolvable into others more simple. It is not to be inferred, however, from the rash attempts to establish principles of intuitive belief which do not exist, that there are no such principles in our mental constitution, any more than it is to be inferred, from the general prevalence of bad reasoning, that it is impossible for a human being to reason accurately. I trust, at any rate, that I have already sufficiently warned you, against the danger of acquiescing too soon in any proposition, as a law of thought, precluding all further inquiry, from its own primary and independent evidence; and that I have impressed you, not merely with the necessity of admitting some principles of this sort, as essential to every reasoning, but with the necessity also, of admitting them, only after the most cautious examination.

The difficulty of ascertaining precisely, whether it be truth which we have attained, is, in many cases, much greater, than the difficulty of the actual attainment. Philosophy has in this respect been compared, by a very happy illustration,—which, therefore, homely and familiar as it is, I make no scruple to quote,—to “a game at which children play, in which one of them, with his eyes bandaged, runs after the others. If he catch any one, he is obliged to tell his name; and if he fail to name him, he is obliged to let him go, and to begin his running once more. It is the same,” says Fontenelle, the author from whom I borrow this image, “in our seeking after truth. Though we have our eyes bandaged, we do sometimes catch it.—But then we cannot maintain with certainty that it is truth, which we have caught;—and in that moment it escapes from us.”

If there be, as it has been already shewn that there must be, intuitive truths; and, if we are not to reject, but only to weigh cautiously, the belief which seems to us intuitive, it will be difficult to find any, which has a better claim to this distinction, than the faith which we have, in our identity, as one continued sentient and thinking being, or rather, to speak more accurately, as one permanent being capable of many varieties of sensation and thought.

There is to be found in it, every circumstance which can be required to substantiate it as a law of intuitive belief. It is universal, irresistible, immediate. Indeed, so truly prior and paramount is it to mere reasoning, that the very notion of reasoning necessarily involves the belief of our identity as admitted. To reason, is to draw a conclusion from some former proposition; and how can one truth be inferred from another truth, unless the mind, which admits the one, be the mind, which admitted the other? In its order, as much as in its importance, it may be truly considered as the first of those truths which do not depend on reasoning, and as itself necessarily implied, perhaps in all, certainly in the greater number, of our other intuitions. I believe, for example, without being able to infer it, or even to discover the greater probability of it, by any process of reasoning, that the course of nature in future will resemble the past; and, since all mankind have the same irresistible tendency, I have no scruple in referring it to an original principle of our nature. In taking for granted this similarity, however, in the order of succession of two distinct sets of phenomena, I must previously have believed, that I, the same sentient being, who expect a certain order in the future phenomena of nature, have already observed a certain order in the past.

Since, then, the belief of our identity is intuitive and irresistible, the only inquiry which remains is as to the circumstances in which the belief arises. Identity is a relative term. It implies of course, in every instance, a double observation of some sort. The identity of our mind is its continuance, as the subject of various feelings, or at least as that which is susceptible of various feelings. The belief of it therefore, can arise only on the consideration of its successive phenomena; and is indeed involved in the mere consideration of these as successive.

The knowledge of our mind as a substance, and the belief of our identity during successive feelings, may be considered as the same notion, expressed in different words. Our identity is the unity and sameness of that which thinks and feels,—itself substantially unchanged amid the endless variety of its thoughts and feelings,—capable of existing separately in all these different states; not ceasing therefore when they cease, but independent of their transient changes. The knowledge of mind, then, as a substance, implying the belief of identity during changes of state cannot be involved in any one of these separate states; and, if our feelings merely succeeded each other, in the same manner as the moving bodies of a long procession are reflected from a mirror, without any vestige of them as past, or consequently, any remembrance of their successions, we should be as incapable of forming a notion of the sentient substance mind, abstracted from the momentary sensation, as the mirror itself; though we should indeed differ from the mirror, in having what mind only can have, the sensations themselves, thus rapidly existing and perishing.

But, if it be only on the consideration of some past feeling, that the belief of the permanent substance mind can arise, it is to the principle which recals to us past feelings, that the belief is ultimately to be traced. We remember;—and in that remembrance is involved the belief, the source of which we seek. It is not merely a past feeling that arises to us, in what is commonly termed memory, but a feeling that is recognized by us as ours, in that past time of which we think,—a feeling, therefore, of that mind which now remembers what it before saw, perhaps, or heard, or enjoyed, or suffered. We are told by writers on this subject, that it is from a comparison of our present with our past consciousness, that the belief of our identity in these states arises; and this use of the term comparison, which is commonly applied to a process of a different kind, may perhaps mislead you as to this simpler process. It is true, indeed, that the belief arises from a feeling of the past, that is remembered, together with the consciousness of our remembrance as a present feeling,—a contemplation, as it were, of two successive states of the mind. But the comparison is nothing more than this.—It is not to be supposed that we discover in the two feelings some common quality or proportion, as when, in arithmetic or geometry we compare two numbers, or two regular figures; for the two feelings may have nothing common, except that very belief of identity which is involved in the remembrance itself. We remember the past,—we feel the present,—we believe, and cannot but believe, that the rememberer of the past existed in that past which he remembers. The process itself is sufficiently simple, however truly wonderful one of the feelings may be which forms the most important part of the process;—for we are not to forget that the remembrance itself, the revealer of the past, is not a past, but a present feeling. It is the mind existing for the present moment in a particular state, as much as any primary and immediate sensation is the mind existing in a particular state. That this state of remembrance, itself a present feeling, should be representative to us of some former feeling, so as to impress us irresistibly with the belief of that former state of the mind, is indeed most wonderful; but that it does impress us with this belief, is as undeniable as the belief itself is irresistible.

Our faith in our identity, then, as being only another form of the faith which we put in memory, can be questioned only by those who deny all memory, and with memory all reasoning of every kind,—who believe only the existence of the present moment, and who with respect to every thing else, are as incapable of opposing or questioning as they are of believing. If our memory be unworthy of the faith which we intuitively give to it, all that is founded on memory, and therefore demonstration itself, must equally deceive us. We cannot admit the most rigid demonstration, or expect it to be admitted, without having already admitted, intuitively, that identity, which in words only we profess to question, and to question which, even in words, is to assert the reality of that which we deny.

The belief of the identity of self, then, as the one permanent subject of the transient feelings remembered by us, arises from a law of thought, which is essential to the very constitution of the mind. It has accordingly all the qualities, which I can imagine to be required by the most rigid scrutinizer of our principles of intuitive assent. It is universal, and immediate, and irresistible. I do not believe, with more confidence, that the half of thirty-two is equal to the square of four, than I believe, that I, who computed the square of four, am the same with that mind, which computes the half of thirty-two, and asserts the equality of the two numbers.

This consideration is of itself decisive of the question of identity; since, if it be manifest, that there is an universal, immediate, and irresistible impression of our identity,—an impression, which cannot be traced to any law of thought more simple,—its truth is established by a species of evidence, which must be allowed to be valid, before the very objections can be put, in which it is professedly denied;—every objection, however sceptical, involving, as we have seen, and necessarily involving, the assertion of some such intuitive proposition, from which alone its authority, if it have any authority, is derived. In endeavouring to move the whole world of truth with his lever, there must still be some little spot at least, on which the sceptic must be content to rest his foot as firmly as others. Δὸς ποῦ στῶ, he must still be condemned to say with Archimedes; and if we allow no resting-place to his foot,—or, even allowing him this, if we allow no fulcrum for the instrument which he uses, he may contract or lengthen his lever at pleasure; but all the efforts, which in such circumstances, he can make, will exhibit nothing so striking to those by whom the efforts are witnessed, as the laborious impotence of him who employs them. To deny any first principles of intuitive belief, that are not themselves to stand in need of a demonstration,—which, as a demonstration, or series of consecutive propositions, can be founded, in its primary evidence, only on some principle of the same kind,—is, indeed, for such a sceptical mechanic, to set his foot upon air, rather than on the ground, on which all around him are standing, and to throw away the single fulcrum on which his lever rests, and from which alone all its power is derived.

The belief of our mental identity, then, we may safely conclude, is founded on an essential principle of our constitution,—in consequence of which, it is impossible for us to consider our successive feelings, without regarding them as truly our successive feelings—states, or affections of one thinking substance. But though the belief of the identity of the substance which thinks, is thus established on the firmest of all grounds, the very ground, as we have seen, on which demonstration itself is founded,—even though no particular fallacy could be traced in the objections brought against it, which I detailed in my last Lecture,—it is still an interesting inquiry, in what the fallacy of the objections consists; and the inquiry is the more interesting, as it will lead us to some remarks and distinctions, which, I flatter myself, will throw some light on the philosophy of all the changes, material as well as mental, that are every moment taking place in the universe.

The objections brought against the identity of the mind, from a supposed incompatibility of its diversities of state with sameness of substance, appear to me to depend on the assumption of a test of identity, transferred, without sufficient reason, from the obvious appearances of matter to mind, and which, if matter be accurately considered, is equally false, too, as applied to it. The cause of the transference, however, from the obvious material appearances, is a very natural one,—the same, which has included so many analogies, from external things, in the language, which we employ to express the intellectual functions. It is with the changes of the material substances around us, that all our operations, which leave any fixed and permanent marks of our agency, are immediately concerned. It is indeed only through them, that our communication with other minds can be at all carried on; and it is not wonderful, therefore, that, in considering the nature of change, of every kind, our philosophy should be strongly tainted with prejudices, derived from the material world, the scene of all the immediate and lasting changes, which it is in our power to produce. How much the mere materialism of our language has itself operated, in darkening our conceptions of the nature of the mind, and of its various phenomena, is a question, which is obviously beyond our power to solve; since the solution of it would imply, that the mind of the solver was itself free from the influence which he traced and described. But of this, at least, we may be sure, that it is almost impossible for us to estimate the influence too highly; for we must not think, that its effect has been confined to the works of philosophers. It has acted, much more powerfully, in the familiar discourse, and silent reflections of multitudes, that have never had the vanity to rank themselves as philosophers,—thus incorporating itself, as it were, with the very essence of human thought. In that rude state of social life, in which languages had their origin, the inventor of a word probably thought of little more, than the temporary facility, which it might give to himself and his companions, in communicating their mutual wants, and concerting their mutual schemes of co-operation. He was not aware, that, with this faint and perishing sound, which a slight difference of breathing produced, he was creating that which was afterwards to constitute one of the most imperishable of things, and to form, in the minds of millions, during every future age, a part of the complex lesson of their intellectual existence,—giving rise to lasting systems of opinions, which, perhaps, but for the invention of this single word, never could have prevailed for a moment, and modifying sciences, the very elements of which had not then begun to exist. The inventor of the most barbarous term may thus have had an influence on mankind, more important, than all which the most illustrious conqueror could effect, by a long life of fatigue, and anxiety, and peril, and guilt. Of the generalship of Alexander, and the valour of his armies,—of all which he suffered, and planned, and executed, what permanent vestiges remain, but in the writings of historians! In a very few years, after the termination of his dazzling career, every thing on the earth was almost as if he had never been. A few phrases of Aristotle achieved a much more extensive and lasting conquest, and are, perhaps, even at this moment, exercising no small sway on the very minds which smile at them with scorn, and which, in tracing the extent of their melancholy influence on the progress of science, in centuries that are past, are unconscious that they are describing and lamenting prejudices, of which they are themselves still, in a great measure, the slaves. How many truths are there, of which we are ignorant, merely because one man lived!

To return, however, to the objections, which we are to consider.

Diversity of any kind, it is said, is inconsistent with absolute identity, in any case, and in the mind, which is by supposition indivisible, nothing can be added to it or taken away, and no internal change can take place, in the relative positions and affinities of parts which it has not. Joy and sorrow are different in themselves; that which is joyful, therefore, and that which is sorrowful, cannot be precisely the same, or diversity of any kind might be consistent with absolute identity. That the joyful and sorrowful mind are precisely the same, is not asserted, if the sameness be meant to imply sameness of state; for it is admitted, that the state of the mind is different in joy and sorrow! and the only question is, whether this difference, to which we give the name of difference of state, be incompatible with complete and absolute sameness of substance.

The true key to the sophistry is, as I have already said, that it assumes a false test of identity, borrowed, indeed, from the obvious appearances of the material world, but from these obvious appearances only. Because diversity of any kind seems, in these familiar cases, to be inconsistent with absolute identity, we draw hastily the universal conclusion, that it is inconsistent with absolute identity in any case. Paradoxical as the assertion may appear, however, we may yet safely assert, that, not in mind only, but, as we shall find, in matter also; some sort of diversity is so far from being inconsistent with absolute identity, that there is scarcely a single moment, if, indeed, there be a single moment, in which every atom in the universe is not constantly changing the tendencies that form its physical character, without the slightest alteration of its own absolute identity; so that the variety of states or tendencies of the same identical mind, in joy and sorrow, ignorance and knowledge, instead of being opposed, as you might think, by the general analogy of nature, is in exact harmony with that general analogy. It is from our view of matter, unquestionably, as implying, in all its visible changes of state, some loss of identity, some addition or subtraction of particles, or change of their form of combination, that the objection, with respect to the identity of the mind, during its momentary or lasting changes of state, is derived; and yet we shall find, that it is only when we consider even matter itself superficially and slightly, that we ascribe the changes which take place in it, to circumstances that affect its identity. To view it more profoundly and accurately, is to observe, even in matter, constant changes of state, where the identity has continued entire, and changes as opposite, as those of the mind itself, when, at different periods, it presents itself in different aspects, as sad and cheerful, ignorant and wise, cruel and benevolent.

The apparent mystery of the continued identity of one simple and indivisible mind, in all the variety of states, of which it is susceptible, is thus in a great measure, solved, when we find this union of variety and sameness to be the result of a law that is not limited to our spiritual being, but extends to the whole universe, or at least to every thing which we know in the universe. It can no longer appear to us peculiarly wonderful, that the mind should exist at different moments in opposite states, and yet be the same in its own absolute nature, when we shall find that this compatibility is true of every atom around us, as much as of the mind itself.

[LECTURE XIV.]

CONTINUATION OF THE ANSWER TO OBJECTIONS AGAINST THE DOCTRINE OF MENTAL IDENTITY.

My Lecture yesterday was, in a great measure, employed in illustrating the primary evidence of those principles of intuitive assent, to which we traced our belief of the identity of the mind as one and permanent, in all the variety of its ever-changing affections. I explained to you, particularly with a view to that vague and not very luminous controversy, in which Dr Priestley was engaged with some philosophers of this part of the Island, in what manner the truth of these intuitive propositions must be assumed or admitted by all who reason, even by the wildest sceptic who professes to question them; pointing out to you, at the same time, the danger to which two of the strongest principles of our constitution, our indolence and our love of knowledge, alike expose us—the danger of believing too soon that we have arrived at truths which are susceptible of any minuter analysis. In conformity, therefore, with the caution which this danger renders necessary, we examined the belief of our continued identity; and we found it to possess the distinguishing marks, which I ventured to lay down as the three great characters of intuition, that it is universal, immediate, and irresistible;—so universal, that even the very maniac, who conceives that he was yesterday emperor of the Moon, believes that he is to-day the very person who had yesterday that empire—so immediate, that we cannot consider any two feelings, of our mind as successive, without instantly considering them as feelings of our mind, that is to say, as states of one permanent substance, and so irresistible that even to doubt of our identity, if it were possible for us truly to doubt of it, would be to believe, that our mind, which doubts, is that very mind which has reflected and reasoned on the subject.

Having thus stated the positive ground of belief, in our spiritual identity, I proceeded to consider the negative evidence which might arise from the confutation of the objections urged against it,—objections drawn from the supposed incompatibility of the changes of our mental affections, with that strict absolute identity of substance, to which nothing can have been added, and from which nothing can have been taken away. The test of identity, which this supposed incompatibility implies, I stated to be a very false one, transferred from matter to mind, and borrowed, not from a philosophical, but from a very superficial view even of matter itself. If it appear, on a closer inquiry, that matter itself, without the slightest loss of identity, exists at different moments, in states which are not merely different but opposite, and exists in almost infinite variety of such states, it cannot surely seem wonderful, that the mind also should, without the slightest loss of its identity, exist at different moments, in states that are different and opposite.

That a superficial view of matter, as it presents itself to our mere organs of sense, should lead us to form a different opinion, is, however, what might readily be supposed, because the analogies, which that superficial view presents, are of a kind that seem to mark a loss of identity whenever the state itself is altered.

In experimental philosophy, and in the obvious natural phenomena of the material world, whenever a body changes its state, some addition or separation has previously taken place. Thus, water becomes steam by the addition, and it becomes ice by the loss, of a portion of that matter of heat which is termed by chemists caloric; which loss and addition are, of course, inconsistent with the notion of absolute numerical identity of the corpuscles, in the three states of water as a solid, a liquid, and a gaseous vapour. Perception, by which the mind is metaphorically said to acquire knowledge, and forgetfulness, by which it is metaphorically said to lose knowledge, have, it must be confessed, a very striking analogy to these processes of corpuscular loss and gain; and, since absolute identity seems to be inconsistent with a change of state in the one set of phenomena, with which we are constantly familiar, we find difficulty in persuading ourselves, that it is not inconsistent with a change of state in the other set also. It is a difficulty of the same kind as that which every one must have felt, when he learned, for the first time, the simple physical law, that matter is indifferent as to the states of motion and rest, and that it requires, therefore, as much force to destroy completely the motion of a body, as to give it that motion when at rest. We have not been accustomed to take into account the effects of friction, and of atmospherical resistance, in gradually destroying, without the interference of any visible force, the motion of a ball, which we are conscious of effort in rolling from our hand; and we think, therefore, that rest is the natural state of a body, and that it is the very nature of motion to cease spontaneously. “Dediscet animus sero, quod dedicit diu.” It is a very just saying of a French writer, that “it is not easy to persuade men to put their reason in the place of their eyes; and that when, for example, after a thousand proofs, they are reasonable enough to do their best to believe, that the planets are so many opaque, solid, habitable orbs, like our earth, they do not believe it in the same manner as they would have done if they had never looked upon them in another light. There still comes back upon their belief something of the first notion which they had, that clings to them with an obstinacy, which it requires a continual effort to shake off.”[49]

It is, then, because some substantial loss or gain does truly take place in the changing phenomena of the bodies immediately around us, to which we are accustomed to pay our principal attention, that we learn to regard a change of state in matter as significant of loss of identity, and to feel, therefore, some hesitation in admitting the mental changes of state to be consistent with absolute sameness of substance. Had our observation of the material phenomena been different, there would have been a corresponding difference in our view of the changes of the phenomena of the mind.

If, for example, instead of previously gaining or losing caloric,—as in the constitution of things of which we have our present experience,—the particles of the water had suddenly assumed the state of vapour on the sounding of a trumpet at a distance, and the state of ice immediately on the rising of the sun,—-in short, if the different changes of state in bodies, by which their physical character for the time seems, in many cases, to be wholly altered, had occurred without any apparent loss or gain of substance, we should then no longer have found the same difficulty in admitting the changes of state in mind as consistent with its identity; and the sentient substance, which previously existed in a different state, might then, on the sounding of a trumpet, have been conceived by us to begin to exist, in the state which constitutes that particular sensation of hearing, or, on the rising of the sun, to exist in that different state which constitutes the sun's change of colour as readily as the material substance, previously existing in the form of water, to begin at the same moment, without any essential or numerical change, and consequently with perfect identity, to exist in the new state of steam, or in the state of a chrystalline mass, as solid as the rock from which it hangs as an icicle, or that glitters with its gemmy covering.

But it may be said, that the very supposition which we now make is an absurd one; that the mere presence of the sun in the firmament, at a distance from the water, cannot be supposed to convert it into ice, unless the water gain or lose something, and consequently cease to have absolute identity; and that the case, therefore, is of no value, as illustrating the compatibility of change of state in our various sensations, with unaltered identity of the sentient mind. To this I might answer, that although the presence of the sun certainly does not operate in the manner supposed,—as the sequences of events are now arranged in the great system of nature,—it is only by experience, and not by intuition or reasoning, we know, that the presence of the sun has not the very effect which the separation of caloric now produces, and that there is nothing absolutely more wonderful in the one case than in the other. If our experience had been the reverse of this,—if the change of place of a few particles of caloric had not, as now, converted the liquid water into that solid congeries of crystals which we call ice,—we should then have found as little difficulty in conceiving that it should not have this effect, as we now find in adapting our belief to the particular series of events which constitute our present experience.

It is not necessary, however, to have recourse to suppositions of this kind; since the system of nature, even according to our present experience of it, furnishes sufficient proof of changes as wonderful in the state of bodies produced obviously at a distance, and, therefore, without any loss or addition which can affect their identity. For sufficient evidence of this, I need appeal only to the agency of the celestial gravitation; that gigantic energy of nature which fills the universe, like the immediate presence of the Deity himself,—to which, in the immensity of its influence, the distances, not from planets to planets merely, but from suns to suns, are like those invisible spaces between the elements of the bodies around us, that seem actual contact to our eyes,—and in comparison with which, the powers, that play their feeble part in the physical changes on the surface of our earth, are as inconsiderable as the atoms, on which they exercise their little dominion, are to the massy orbs which it wields and directs at will,—

“Those bright millions of the heavens,

Of which the least full Godhead had proclaim'd,

And thrown the gazer on his knee.”—“Admire

The tumult untumultuous! All on wing,

in motion all; yet what profound repose!

What fervid action, yet no noise!—as aw'd

To silence by the presence of their Lord.”

The action of these great planetary bodies on each other,—it surely cannot be denied,—leaves them separate identities, precisely as before; and it is a species of agency, so essential to the magnificent harmony of the system, that we cannot conceive it to have been interrupted, for a single moment, since the universe itself was formed. An action, therefore, has been constantly taking place on all the bodies in the universe,—and consequently a difference of some sort produced,—which yet leaves their identities unaffected. But, though the identity of the substance of the separate orbs is not affected by their mutual attractions, the state, or temporary physical character, of these orbs,—considered individually as one great whole,—must be affected,—or it would be absurd to speak of their mutual agency at all; for action implies the sequence of a change of some sort, and there can be no action, therefore, where the substances continue precisely the same, and their state also precisely the same, as before the action. Accordingly, we find, on our own globe, that great changes of state, such as form the most striking of its regular visible phenomena, are produced by this distant operation. The waters of our ocean, for example, rise and fall,—and, therefore, must have altered states, or physical tendencies, in consequence of which they rise and fall, as there is no corresponding addition or subtraction of matter,—at regular intervals,—which it is in our power to predict with infallible accuracy,—not because we can divine any loss of identity in the fluid mass,—any internal change in its elementary composition, or the nature and varieties of the winds, which are to sweep along its surface,—but because we know well, at what hours, and in what relative situation, a certain great body, at the distance of some hundreds of thousands of miles, is to be passing along the heavens.

If, then, the mere position of a distant heavenly body can cause the particles of our ocean to arrange themselves in a different configuration,—from that in which they would otherwise have existed, and, therefore, must have produced in the particles that change of state, which forces them, as it were, into this altered form,—without addition to them of any thing, or subtraction of any thing,—in short, leaving in them the same absolute numerical or corpuscular identity as before,—there surely can be no greater difficulty, in supposing, as in the case before imagined, that a certain position of the sun might have immediately caused the particles of a distant liquid, to arrange themselves in the particular configuration, that constitutes the solid ice,—which, though perhaps a more striking change of state, would not have been more truly a change of state, than that, which it now unquestionably produces, in modifying the rise or fall of our tides. And, if a distant body can produce in matter a change of state, without affecting its identity, by any addition or subtraction, we may surely admit, that the presence of an external body, as in perception, may, in mind also, produce a change of state, without affecting its identity; unless indeed, (which is not impossible, because nothing is impossible to human folly,) we should be inclined to reverse our prejudices, and maintain, that matter may be easily conceived to change the affinities or tendencies that form its physical character, in the particular circumstances observed, without any addition or subtraction of substance, but that some positive addition or subtraction of substance is, notwithstanding, essential to the simple changes or affections of the mind.

If the moon were suddenly annihilated, our earth would still be the same identical planet, without the loss or gain of a single particle of substance. But the state of this planet, as a whole, and of every atom of this planet, would be instantly altered, in many most important respects,—so completely altered, indeed, that not an atom of the mass would tend to the other atoms of the mass, in the same manner as before. In like manner, if the light,—which now, operating on one of my organs of sense, causes my mind to exist in the state that constitutes the sensation of a particular colour,—were suddenly to vanish, the state of my mind would be instantly changed, though my mind itself, considered as a substance, would still continue unaltered. In both cases,—the spiritual, and the material,—and in both cases, alike,—absolute identity, in the strictest sense of the term, is consistent with innumerable diversities.

In the discussion of this supposed difficulty, I have chosen, for illustration, in the first place, to consider the planetary attractions, in preference to those which occur, in the minuter changes, that are simply terrestrial; because in the case of operations at a distance, it is impossible for us, not to perceive, that, even in matter, a change of state is not inconsistent with complete permanence of absolute corpuscular identity; while, in the compositions or decompositions, that occur spontaneously, or by artificial experiment, in the physical changes on the surface of our earth, the additions or subtractions of matter, that appear to us to constitute these phenomena, truly destroy the corpuscular identity of the substances, in which the change takes place; and the change of state is thus considered by us, as implying a positive substantial change. But when we examine even these phenomena a little more deeply, we shall find, that, like the great operations of gravitation on the masses of the universe,—the change, in these also, is not a positive change of substance, but is simply a change of state in a congeries of independent substances, which we term one substance, merely because the spaces, that are really between them, are imperceptible to our very imperfect organs; the addition or subtraction of matter being not that which constitutes the new states or tendencies of the particles which continue present, but merely that which gives occasion to those changes of state or tendency;—as the positions of the heavenly bodies do not constitute the phenomena of our tides, but merely give occasion to that difference of state in the particles of the ocean, in consequence of which they assume of themselves a different configuration. Man is placed, as it has been truly said, on a point, between two infinities,—the infinitely great, and the infinitely little. It may be an extravagant speculation, to which I have before alluded,—but it is not absolutely absurd, to suppose, that in the unbounded system of nature, there may be beings, to whose vision the whole planetary attendants of each separate sun, which to us appear to revolve at distances so immense, may yet seem but one small cohesive mass, in the same manner, as to those animalculæ, whose existence and successive generations had been altogether unknown to man, till the microscope created them, as it were to his feeble sight,—and which, perhaps, are mighty animals compared with races of beings still more minute, that are constantly living in our very presence, and yet destined never to be known to us,—those bodies, which to us seem one small cohesive mass, may appear separated by distances, relatively as great, as to us are those of the planets. That light, itself a body, should pass freely through a mass of solid crystal, is regarded by us as a sort of physical wonder; and yet it is far from impossible, that, between the atoms which compose this apparently solid mass, whole nations of living beings maybe dwelling, and exercising their mutual works of peace or hostility; while perhaps, if philosophy can be exercised, in brains of such infinitesimal dimensions, in the same manner as in our coarser organs, the nature of the atoms, or distant worlds around them, may be dividing with endless absurdities, the Ptolemies and Aristotles of the little republics. We have all so much of the nature of the inhabitants of Brobdignag, that a supposition of this kind,—which is perhaps truly in itself not a very probable one,—yet appears to us much more improbable, than it really is. We smile, as recognizing our own nature, when the sovereign of that country of giants is represented by the most unfortunate, or rather the most fortunate of all voyagers, as “turning to his first minister, who waited behind him with a white staff, near as tall as the mainmast of the Royal Sovereign, and observing how contemptible a thing was human grandeur, which could be mimicked by such diminutive insects.” “And yet,” said he, “I dare engage, those creatures have their titles and distinctions of honour; they contrive their nests and burrows, that they call houses and cities; they make a figure in dress and equipage; they love, they fight, they dispute, they cheat, they betray.” And we fully enter into the difficulty which the savans of the country, who had all agreed that the new-discovered animal could not have been produced according to the regular laws of nature, must have found, in giving him a name. “One of them seemed to think that I might be an embryo, or abortive birth. But this opinion was rejected by the other two, who observed my limbs to be perfect and finished; and that I had lived several years, as it was manifest from my beard, the stumps whereof they plainly discovered through a magnifying-glass. They would not allow me to be a dwarf, because my littleness was beyond all degrees of comparison; for the queen's favourite dwarf, the smallest ever known in that kingdom, was near thirty feet high. After much debate, they concluded unanimously, that I was only relplum scalcath, which is interpreted literally lusus naturæ; a determination exactly agreeable to the modern philosophy of Europe, whose professors, disdaining the old evasion of occult causes, whereby the followers of Aristotle endeavoured in vain to disguise their ignorance, have invented this wonderful solution of all difficulties, to the unspeakable advancement of human knowledge.”[50]

Whatever may be thought of speculations of this kind, however, with respect to the relative distance of the atoms of bodies, it is not the less certain, that these atoms are separate substances, independent of the other similar or different substances that apparently adhere to them in continuity,—that they are, in truth, the only material substances which really exist, since the bodies which we term masses are only those very atoms under another name,—that they remain, and cannot but remain, identical, amid all the changes of chemical composition or decomposition,—and that the change which they suffer, therefore, however strikingly their physical character may be altered for the time, is a change not of substance but of state only. In the case of the formation of ice, for example, the elementary atoms themselves, which are all that truly exist in nature, are not, and cannot be, changed; but particles, which were formerly easily separable from adjacent particles, now resist this separation by a considerable force. There is a change in their state, therefore, since they now exist with a different degree of tendency toward each other,—a change, to which the separation of a quantity of caloric may, indeed, have given occasion, but which is to be distinguished from that momentary separation itself, since the solidity, which is only another name for the corpuscular resistance, continues after the separation is complete, and would continue forever, unless a change of temperature were again to restore that former state or tendency of the particles, in which they were easily separable. To him who has learned to consider bodies as, what they truly are, a multitude of separate and independent corpuscles, there is no change of identity, and cannot be any change of identity, in all the phenomena or changes of the universe. The atoms, which alone existed, continue as before; and all which constitutes the phenomenon, or varieties of successive phenomena, is a change of their place or tendency.

This corpuscular view of the material universe,—which, of course, admits an infinite variety of applications, corresponding with the infinite variety of its phenomena,—has many most striking analogies in that moral universe, with the phenomena of which we are chiefly concerned. Indeed, when we consider any of the masses before us, as deriving all its apparent magnitude from a number of separate bodies, of which it is composed,—any one of which, individually, would be too minute to be distinguishable by us,—it is scarcely possible not to think of the similarity which it presents to the multitudes of human beings that are as it were, massed together in the great nations of the earth; and in which any single individual, if he could be supposed to have exercised his powers separately, would have been truly as insignificant as a single atom separated from the mass of which it is a part. What we call the greatness of a nation, is nothing more than the union of a number of little interests and little passions joined in one common object; to which insignificant elements, so wonderful when combined, if we could distinctly reduce, by analysis, the most unrivalled power that has ever commanded the admiration and envy of the world, it would, at first view, run some little risk of appearing contemptible. The advantages of this social union of mankind, as silently felt at every moment, are unquestionably so infinite in comparison, as almost to sink into nothing the occasional evils to which the aggregation and massing of so many powers, when ill directed, may give rise,—though these terrific evils, when they occur, may dwell more permanently in the mind;—like the visitations of storms and earthquakes, which we remember forever, while, with a sort of thankless forgetfulness, we scarcely think of the calm beauty and regularity which, season after season, passes over us. The rock which, descending from the top of a mountain, lays waste whatever it meets in its progress,—and to attempt to stop which, while its short career lasts, would be almost like instant annihilation,—derives this overwhelming force from an infinite number of independent corpuscles, any one of which, if it had fallen singly, would have been far less destructive than the flutter of an insect's wing; and that tyrannical power of a single man, before which, in unhappy ages of successful oppression, the earth has so often trembled,—as before some power of darkness, endowed with more than human sway,—has derived its irresistible might, not from powers included in itself,—which, in reference to the objects achieved by it, would have been feeble indeed,—but from the united powers of beings still feebler, who were trembling while they executed commands to which themselves alone gave omnipotence.

To this corpuscular view, however, though it is unquestionably the sort of view to which, in our ultimate physical inquiries into the phenomena of matter, we must come, you may, perhaps, not be sufficiently accustomed, to enter fully into the reasoning on the subject. It will probably be less difficult for you, if we take rather, as an illustration, the simpler case of impulse; in which the bodies affecting each other are not, as in chemistry, indistinguishable corpuscles, but masses, clearly defined, and easily perceptible.

I need not, of course, repeat the arguments formerly stated, to prove that attraction, however general it may be as a law of matter at all visible distances, does not continue, but gives place to an opposite tendency at those smaller distances, which we are unable to perceive with our weak organs, and which we learn to estimate only by effects that are inconsistent with absolute contact;—for example, by the well-known fact of the compressibility of bodies, which could not take place if their particles were already in contact, and which by continually increasing resistance to the compressing force that would bring the corpuscles nearer, shews, that there is, at different degrees of nearness, a tendency continuing to operate, which is the very reverse of attraction. There is, therefore, every reason to believe,—since repulsion, as the fact of forcible compression shews, takes place while the particles of bodies are still at a certain distance,—that the motion produced in one body by another, and ascribed to immediate impulse, is produced, without actual contact, by this mutual repulsion, as it is called, of the bodies when brought within a certain invisible degree of vicinity to each other; or, in other words,—for repulsion means nothing more mysterious than this simple fact,—the tendency which bodies, in certain relative positions of apparent but not actual contact, have to fly off from each other with certain degrees of velocity, as in certain other relative positions, of distinguishable distance, they have a tendency to approach each other. This repulsion, or tendency from each other at one point of nearness, is of itself as easy to be conceived, as that attraction, or tendency toward each other at other points of distance, to which we give the name of gravitation; and it is only from our greater familiarity with the one, as operating at distances which are visible, while the other,—except in a few cases, such as those of magnetism and electricity,—operates only at distances which are imperceptible to us, that we feel a little more difficulty in admitting the repulsion than the attraction of matter. There is then,—however universal gravitation may seem, when we think only of perceptible distances,—a certain point of near approach, before actual contact, at which gravitation ceases; and, beyond this point, the tendency of bodies toward each other is converted,—as the force necessary to compress them evidently shews,—into a tendency from each other; both tendencies, indeed, being inexplicable, but the one in no respect more so than the other.

For this apparent digression, on a point of general physics, I make no apology, as it is absolutely necessary for illustrating the particular case to which I am to proceed. The consideration of it requires, what the whole of this discussion, indeed, has already required from you, no small exercise of patient attention; but I trust that I sufficiently prepared you for this, in a former Lecture, when I stated the importance of such attention, not merely in relation to the subject considered at the time, but as a part of your mental discipline, and the advantage which might thus be derived to your intellectual character, from the very difficulties which the subject presents. It is in philosophy, as in many a fairy tale. The different obstacles which the hero encounters, are not progressively greater and greater; but his most difficult achievements are often at the very commencement of his career. He begins, perhaps, with attacking the castle of some enchanter, and has to force his way, unassisted, through the griffins and dragons that oppose his entrance. He finishes the adventure, with the death of the magician—and strips him of some ring, or other talisman, which renders his subsequent adventures comparatively easy and secure. I cannot venture to say, indeed, that a perfect acquaintance with the difficulties of the present question, and of some of the late questions which have engaged us, will be such a talisman to you, in your future career of intellectual science. But I may safely say, that the habit of attentive thought, which the consideration of subjects, so abstract, necessarily produces, in those who are not too indolent to give attention to them, or too indifferent to feel interest in them, is more truly valuable than any talisman, of which accident or force might deprive you. The magic with which this endows you, is not attached to a ring, or a gem, or any thing external; it lives, and lives forever, in the very essence of your minds.

When a billiard ball, on being struck, approaches another, which is at rest, it soon arrives at the point of seeming, but not actual contact, at which their mutual attraction ceases, and the force which it has acquired still carrying it on, it passes this bounding point, and arrives at a point at which repulsion has already begun. Accordingly the body, formerly at rest, now flies off, on a principle precisely similar, (though the mere direction be opposite) to that by which the same ball, if dropped from a hand that supported it, would, without the actual impulse of any body, have quitted its state of rest, as in the present case, and have gravitated, or, which is the same thing, have moved of itself toward the earth.

Before the first ball, which you will, perhaps more easily remember by the name, A, arrived so very near to the second ball B, as to have come within the sphere of their mutual repulsion, this second ball was at rest, that is to say, it had no tendency to move in any direction. This state of rest, however, is only one of the many states, in which a body may exist; and if, which must surely be allowed, a body having a tendency to continued motion, be in a different state, from one which has no such tendency, this change of state implying, it must be remarked, not even the slightest loss of identity, has been produced in the body B, by the mere vicinity of the body A. For the sake of illustration, let us now suppose this body A to be hot or luminous. It will still, as before, produce the new state of tendency to motion, in B, when it arrives within the limits of their sphere of repulsion. Is it less conceivable, then, that the mere presence of this hot or luminous body should produce the new sensation of warmth, or of colour, which are different states of the sentient mind, without affecting in the slightest degree the identity of the mind itself, than that it should produce, without any loss of absolute identity, in the body B, an immediate tendency, in that body, to move along with a certain velocity, a state as different from that in which it remains at rest, as the sensation of warmth, which is one state of the mind, is different from the sensation of colour, which is another state of the mind? Nor does the parallel end here; for, since a body at rest, acquiring a tendency to begin motion in one particular direction, as, for example, to move north, must be in a different state from that in which it would have been, if it had acquired an instant tendency to move east, or in any other direction; and, the direction once begun, being the same, since a body having a tendency to move with one velocity, must, at every moment of its progress, be in a different state from that in which it has a tendency to move with a different velocity, it is evident, that the mere presence of a body may produce, in a second body, according to the difference of their positions and relative magnitudes, a variety of states, that, when all the varieties of direction, and all the varieties of velocity are estimated together, may be considered as infinite,—equal at least in number, to the different states of which the mind is susceptible, in its almost infinite variety of feelings; and all this without any essential change, that can affect the identity of the quiescent or moving body, or any essential change, that can affect the identity of the mind.

I am aware, that, when you consider, for the first time, this assertion of an infinite variety of states, corresponding with all the innumerable varieties of direction and velocity, in the tendencies of a simple billiard-ball, which, in the various circumstances supposed, appears to us precisely the same, in all its sensible qualities, you may be apt to conceive, that the assertion must be founded on a mistake, and, from the influence of former prejudice may be inclined to think, that, when it exhibits a tendency to begin to move east, at one time, and, at another time, a beginning tendency to move north, this does not arise from any difference of state in itself, but from its being merely carried along by the first ball, which was itself previously moving in one or other of these particular lines of direction. When the elastic billiard-ball, however, bounds away from the ball which strikes it, this supposition is manifestly inapplicable;—and, in all cases, it is the influence only of former prejudice which can lead you to this opinion,—the influence of that prejudice, by which you may have been accustomed to consider impulse, not as inducing a tendency to motion at some little distance, but as involving the necessity of actual contact. To destroy this prejudice, a very little reflection on the phenomena of elastic bodies, in their shocks and mutual retrocessions, is surely all that can be requisite; and if the motion of B, and consequently its tendency to motion, have begun, without contact of A, as it afterwards continues while A, the elastic body which struck it, is moving back in an opposite direction, it could not be by mechanical trusion, as carried along by A, which is still at some points of distance from it when its motion begins, and at still greater distance the longer the motion continues, that B has assumed any one of its variety of states,—that, for example, in which, in one case, it tends to move east, in another case to move north, in one case to move rapidly, in another slowly. To say that the body acquires this new tendency because it is impelled, is only to say that it is impelled because it is impelled. It is an equally idle use of language, to affirm, as if a word could obviate the difficulty instead of merely stating it,—that A, in communicating a different tendency to B, which was before at rest, does this by a principle, or power of repulsion; for this, as I have said, is merely to state in a single word, the regularity in certain circumstances of the very fact asserted. The different tendencies of B, and consequently the different states in which B exists,—are not the less different, in whatever manner the difference may have been produced, or by whatever word, or combination of words, the difference may be expressed. There is no magic, in the phrase, principle of repulsion, or power of repulsion, which can render the same, states or tendencies that are in themselves opposite;—for, as far as we understand the phrase, it expresses nothing more than the invariableness of the simple fact, that in certain circumstances of relative position, bodies have a tendency to fly off from each other, as in certain other circumstances of relative position, which constitute the phenomena of gravitation, they have a tendency to approach. Whatever term we may employ to denote it, it is still a physical fact, that at a certain point of near and seemingly close approach of another mass, a body which was before in a state of rest, acquires immediately a tendency to fly off in different directions, and with different velocities at different times, and consequently, that, if the tendency to begin or to continue motion, in one direction, and with one velocity, be a state different from that which constitutes the tendency to begin or to continue motion in another direction, and with another velocity, the ball B, in these different circumstances, however identical it may be in substance, exists in two different states;—or all states, however different, may be said to be the same.

It may be admitted, then, that the feeling of rapture is a state of mind, completely different from that which constitutes the feeling of agony,—that the sensation of the fragrance of a rose, has no resemblance to our conception of a sphere or of an equilateral triangle,—and that, in general, all those thoughts and emotions, which,—more truly than the mere union of the immortal spirit within us with the body which it animates,—may be said to constitute life,

“Love, Hope, and Joy, fair Pleasure's smiling train,—

Hate, Fear, and Grief, the family of Pain;”

these, as they prevail, in different hours, render the same individual mind more unlike to itself, if its states or tendencies alone, and not its substantial identity be considered, than the minds perhaps of any two human beings, at the same moment. But still, as we have seen, even from the analogy of the material world,—which was supposed to furnish a powerful objection, it is no argument against the absolute identity of the mind, that exists in different states, however opposite, any more, than it is an argument against the absolute identity of a body, that it, at one moment, has a tendency to one particular motion,—at another moment a tendency to a different motion,—and at another moment, no tendency whatever to motion of any kind; since, in all these cases, as much as in the varying affections of the mind, there is a change of state, with absolute identity of substance.