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.