It must be recollected that certitude is a deliberate assent given expressly after reasoning. If then my certitude is unfounded, it is the reasoning that is in fault, not my assent to it. It is the law of my mind to seal up the conclusions to which ratiocination has brought me, by that formal assent which I have called a certitude. I could indeed have withheld my assent, but I should have acted against my nature, had I done so when there was what I considered a proof; and I did only what was fitting, what was incumbent on me, upon those existing conditions, in giving it. This is the process by which knowledge accumulates and is stored up both in the individual and in the world. It has sometimes been remarked, when men have boasted of the knowledge of modern times, that no wonder we see more than the ancients, because we are mounted upon their shoulders. The conclusions of one generation are the truths of the next. We are able, it is our duty, deliberately to take things for granted which our forefathers had a duty to doubt about; and unless we summarily put down disputation on points which have been already proved and ruled, we shall waste our time, and make no advances. Circumstances indeed may arise, when a question may legitimately be revived, which has already been definitely determined; but a re-consideration of such a question [pg 230] need not abruptly unsettle the existing certitude of those who engage in it, or throw them into a scepticism about things in general, even though eventually they find they have been wrong in a particular matter. It would have been absurd to prohibit the controversy which has lately been held concerning the obligations of Newton to Pascal; and supposing it had issued in their being established, the partisans of Newton would not have thought it necessary to renounce their certitude of the law of gravitation itself, on the ground that they had been mistaken in their certitude that Newton discovered it.

If we are never to be certain, after having been once certain wrongly, then we ought never to attempt a proof because we have once made a bad one. Errors in reasoning are lessons and warnings, not to give up reasoning, but to reason with greater caution. It is absurd to break up the whole structure of our knowledge, which is the glory of the human intellect, because the intellect is not infallible in its conclusions. If in any particular case we have been mistaken in our inferences and the certitudes which followed upon them, we are bound of course to take the fact of this mistake into account, in making up our minds on any new question, before we proceed to decide upon it. But if, while weighing the arguments on one side and the other and drawing our conclusion, that old mistake has already been allowed for, or has been, to use a familiar mode of speaking, discounted, then it has no outstanding claim against our acceptance of that conclusion, after it has actually been drawn. Whatever be the legitimate weight of the fact of that mistake in our inquiry, justice has been done to [pg 231] it, before we have allowed ourselves to be certain again. Suppose I am walking out in the moonlight, and see dimly the outlines of some figure among the trees;—it is a man. I draw nearer,—it is still a man; nearer still, and all hesitation is at an end,—I am certain it is a man. But he neither moves, nor speaks when I address him; and then I ask myself what can be his purpose in hiding among the trees at such an hour. I come quite close to him, and put out my arm. Then I find for certain that what I took for a man is but a singular shadow, formed by the falling of the moonlight on the interstices of some branches or their foliage. Am I not to indulge my second certitude, because I was wrong in my first? does not any objection, which lies against my second from the failure of my first, fade away before the evidence on which my second is founded?

Or again: I depose on my oath in a court of justice, to the best of my knowledge and belief, that I was robbed by the prisoner at the bar. Then, when the real offender is brought before me, I am obliged, to my great confusion, to retract. Because I have been mistaken in my certitude, may I not at least be certain that I have been mistaken? And further, in spite of the shock which that mistake gives me, is it impossible that the sight of the real culprit may give me so luminous a conviction that at length I have got the right man, that, were it decent towards the court, or consistent with self-respect, I may find myself prepared to swear to the identity of the second, as I have already solemnly committed myself to the identity of the first? It is manifest that the two certitudes stand each on its own basis, and the antecedent [pg 232] objection to the admission of a truth which was brought home to me second, drawn from a hallucination which came first, is a mere abstract argument, impotent when directed against good evidence lying in the concrete.

3.

If in the criminal case which I have been supposing, the second certitude, felt by a witness, was a legitimate state of mind, so was the first. An act, viewed in itself, is not wrong, because it is done wrongly. False certitudes are faults because they are false, not because they are (so-called) certitudes. They are, or may be, the attempts and the failures of an intellect insufficiently trained, or off its guard. Assent is an act of the mind, congenial to its nature; and it, as other acts, may be made both when it ought to be made, and when it ought not. It is a free act, a personal act for which the doer is responsible, and the actual mistakes in making it, be they ever so numerous or serious, have no force whatever to prohibit the act itself. We are accustomed in such cases, to appeal to the maxim, “Usum non tollit abusus;” and it is plain that, if what may be called functional disarrangements of the intellect are to be considered fatal to the recognition of the functions themselves, then the mind has no laws whatever and no normal constitution. I just now spoke of the growth of knowledge; there is also a growth in the use of those faculties by which knowledge is acquired. The intellect admits of an education; man is a being of progress; he has to learn how to fulfil his end, and to be what facts [pg 233] show that he is intended to be. His mind is in the first instance in disorder, and runs wild; his faculties have their rudimental and inchoate state, and are gradually carried on by practice and experience to their perfection. No instances then whatever of mistaken certitude are sufficient to constitute a proof, that certitude itself is a perversion or extravagance of his nature.

We do not dispense with clocks, because from time to time they go wrong, and tell untruly. A clock, organically considered, may be perfect, yet it may require regulating. Till that needful work is done, the moment-hand may mark the half-minute, when the minute-hand is at the quarter-past, and the hour hand is just at noon, and the quarter-bell strikes the three-quarters, and the hour-bell strikes four, while the sun-dial precisely tells two o’clock. The sense of certitude may be called the bell of the intellect; and that it strikes when it should not is a proof that the clock is out of order, no proof that the bell will be untrustworthy and useless, when it comes to us adjusted and regulated from the hands of the clock-maker.

Our conscience too may be said to strike the hours, and will strike them wrongly, unless it be duly regulated for the performance of its proper function. It is the loud announcement of the principle of right in the details of conduct, as the sense of certitude is the clear witness to what is true. Both certitude and conscience have a place in the normal condition of the mind. As a human being, I am unable, if I were to try, to live without some kind of conscience; and I am as little able to live without those landmarks of thought which certitude [pg 234] secures for me; still, as the hammer of a clock may tell untruly, so may my conscience and my sense of certitude be attached to mental acts, whether of consent or of assent, which have no claim to be thus sanctioned. Both the moral and the intellectual sanction are liable to be biassed by personal inclinations and motives; both require and admit of discipline; and, as it is no disproof of the authority of conscience that false consciences abound, neither does it destroy the importance and the uses of certitude, because even educated minds, who are earnest in their inquiries after the truth, in many cases remain under the power of prejudice or delusion.

To this deficiency in mental training a wider error is to be attributed,—the mistaking for conviction and certitude states and frames of mind which make no pretence to the fundamental condition on which conviction rests as distinct from assent. The multitude of men confuse together the probable, the possible, and the certain, and apply these terms to doctrines and statements almost at random. They have no clear view what it is they know, what they presume, what they suppose, and what they only assert. They make little distinction between credence, opinion, and profession; at various times they give them all perhaps the name of certitude, and accordingly, when they change their minds, they fancy they have given up points of which they had a true conviction. Or at least bystanders thus speak of them, and the very idea of certitude falls into disrepute.

In this day the subject-matter of thought and belief has so increased upon us, that a far higher mental formation [pg 235] is required than was necessary in times past, and higher than we have actually reached. The whole world is brought to our doors every morning, and our judgment is required upon social concerns, books, persons, parties, creeds, national acts, political principles and measures. We have to form our opinion, make our profession, take our side on a hundred matters on which we have but little right to speak at all. But we do speak, and must speak, upon them, though neither we nor those who hear us are well able to determine what is the real position of our intellect relatively to those many questions, one by one, on which we commit ourselves; and then, since many of these questions change their complexion with the passing hour, and many require elaborate consideration, and many are simply beyond us, it is not wonderful, if, at the end of a few years, we have to revise or to repudiate our conclusions; and then we shall be unfairly said to have changed our certitudes, and shall confirm the doctrine, that, except in abstract truth, no judgment rises higher than probability.

Such are the mistakes about certitude among educated men; and after referring to them, it is scarcely worth while to dwell upon the absurdities and excesses of the rude intellect, as seen in the world at large; as if any one could dream of treating as deliberate assents, as assents upon assents, as convictions or certitudes, the prejudices, credulities, infatuations, superstitions, fanaticisms, the whims and fancies, the sudden irrevocable plunges into the unknown, the obstinate determinations,—the offspring, as they are, of ignorance, wilfulness, [pg 236] cupidity, and pride,—which go so far to make up the history of mankind; yet these are often set down as instances of certitude and of its failure.