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.