way, i.e. by processes of inference. Were our intellect of a much higher order, it is conceivable that we might be able to see equally well, and, at the same time, all those truths which a proposition may contain implicitly as well as explicitly, and all those general laws which particular facts may signify. In that case there would be, of course, no process of inference for us. All those truths we are at present compelled to laboriously gather indirectly, by inference, would then be directly evident to us, just as our own activity and as self-evident fundamental truths are selfevident to us now. Having, however, the relatively imperfect natures we have, we must be content with such roundabout, though practically sufficient, methods as those expressed by our valid processes of reasoning. We must be content to change implicit truths into actual knowledge by placing propositions side by side, so that by such juxtaposition we may be able to see explicitly, truths, otherwise invisible to us, which lie hidden beneath them. They are thus brought to the surface, and seen by us to be "therefore"

true.

Reasoning, then, is a process which is to be trusted in confidently, when carried on logically according to the laws of thought. It is not, however, and cannot be, the highest kind of act of which our intellect is capable. Such highest act is that by which it recognizes truth directly, without adventitious aid-as when it perceives self-evident facts, and those fundamental principles which we have seen also carry with them their own evidence, and need no proof.

Enough has, we trust, here been said in support of the conviction-so continually acted on by us without reflection that some processes of reasoning are valid. We will next proceed to pass in review certain other convictions which are the common property of mankind.

Vulgar

opinion may

taken or

absolutely

true.

CHAPTER VI.

ASSERTIONS AND BELIEFS.

Human testimony and common sense may afford grounds for absolute certainty.

Vulgar opinion may be very mistaken or absolutely true-Human testimony - Common sense — - Conditions necessary to its trustworthiness-Grounds of certainty-Uniformity of Nature-Recapitulation of the section's contents.

AMONGST the convictions respecting matters of everybe very mis day life which are common to men generally, are many which are due to, and rest entirely upon, the assertions of their fellows. Many other convictions seem also to occur to them naturally, without their being able to give any account of them or to defend them, except by saying common sense shows they must be true." But that there are a multitude of vulgar errors current amongst men, and that egregious credulity is far from uncommon, are both notorious facts. So it may, at first sight, seem reasonable for him who would inquire after what things are the most certain, to leave on one side matters of mere popular opinion and vulgar common sense, as being of a nature too uncertain to deserve his notice. But to be guilty of such neglect would be to make a very great mistake; for propositions of the kind may be matters of complete and absolute certainty and therefore must receive some attention from the student of truth. Human testimony, and the spontaneous judgments of uneducated men, may, under special circumstances, both carry with them evidence, to every well-balanced mind, of their absolute veracity.

testimony.

Let us first consider human testimony. That an amount Human of credence which, to us moderns, seems itself hardly credible, was given in uncritical ages to written and spoken assertions respecting matters of the utmost moment, is a fact with which we are all familiar. Persons who, in the

exercise of their profession, have been accustomed to weigh evidence, generally agree that an absolutely correct narration by any witness of a series of events is extremely rare. The untrustworthiness of statements about natural phenomena made by ignorant persons, often becomes ludicrously evident to the man of science, and the main task of our historians is, by careful criticism, to get rid of prevalent delusions due to the mendacity, credulity, or stupidity of their predecessors. In spite of this, no reasonable and well-informed person will deny that he can be forced to believe, with absolute certainty, many matters about which he may have no evidence but that of human testimony. Thus, such a person will not doubt that there was, in 1870, a Franco-German war, or that a revolution took place at Paris in 1848, or that the battle of Waterloo was fought in 1815, and so on. No such person, again, will say he is uncertain whether Sicily is an island; or whether there is a country called Canada; or whether Berlin is the capital of Prussia. When a variety of witnesses of different ages, classes, and interests, uniformly and persistently agree in certifying to a fact not in itself incredible, and one within their competence to testify to, it would be unreasonable to doubt it. For though errors of observation are common enough, yet a number of people thus differing from each other are not likely simultaneously to fall into the very same error of observation; and though many men are liars, yet, in the absence of any common interest, such a variety of people will not concur in telling the same lie. Individuals are liars, and conspiracies to lie are too frequent; but the majority of men do not habitually lie. There is, therefore, a certain probability in favour of the truth of any ordinary assertion, and this probability rapidly increases according to the number and condition. of the witnesses who may add their testimony to it.

It has been objected to this last assertion that the

Common sense.

testimony of one witness can only be "probably" true, and therefore the testimony of many witnesses can also be only "probable," since no number of mere "probabilities" added together can make a "certainty," which is a matter of a different kind. But this objection is groundless, for the following reason: the absence of certainty which we may feel with respect to the evidence of one witness, is not necessarily due to any defect on his part, but may spring from our ignorance as to the possibilities of mistake and unveracity, in any single case. These possibilities, however, rapidly diminish with the increase in number and variety of the independent testimonies borne to any one event, on account of the increasing improbability of a general, simultaneous delusion or deceit. It is, therefore, absolutely impossible for all men to unite in telling one and the same lie-indeed, the idea is so absurd that it may seem superfluous to refer to it; but the reference has its utility, as will appear later on.*

The amount and readiness of credence to be given to assertions, varies with the nature of the assertions and the circumstances of the witnesses, according to rules laid down in special treatises devoted to that subject. What concerns us here is, not any inquiry about what testimony we are to accept, or how we are to test it, but simply the recognition of the fact that human testimony may, under special circumstance, afford amply sufficient grounds for absolute and complete certainty.

Let us next consider those convictions which are said to be due to "common sense." Such judgments are not the result of any conscious reasoning process. They are not reflex mental acts,† and do not refer to abstractions, but are clear, direct judgments about definite matters of fact. They, to a certain extent, resemble the instinctive perceptions of animals, and, as is the case with such perceptions, are not peculiar to individuals, but are the common property of the race. Any ordinary, uneducated men, if asked whether the sun may not begin to ascend on some afternoon instead of setting, or whether winter may not come before Michaelmas Day instead of after, will probably think *See below, ch. xvii., "Ideas of Existence," etc. + See above, p. 3.

that their questioner is either joking or insane, but they will not hesitate as to their own convictions about the sun or the seasons. If pressed to say why they are so certain about such things, they will be pretty sure to reply that to doubt them would be against 'common sense." It does not follow that there are not very good reasons for such common sense judgments-reasons which can be logically drawn out-because the men who make the judgments cannot so draw them out. For example, with respect to the sun and the seasons, they might, if better educated, appeal to "the theory of probabilities," "the principle of causality," and "the laws and conditions of the solar system." Thus the judgments of "common sense" may be well grounded and thoroughly scientific, although those who judge do not see how they are so. It is, indeed, this character of being well grounded, without any distinct, conscious knowledge on the part of those who so judge of the grounds of their judgment, which makes them judgments of "common sense." Now, there is a consideration due to recent advances in science, which greatly enhances the value of "common sense," and should specially incline evolutionists to rely on it. We refer to that theory, according to which, the spontaneous tendencies of the individual are the outcome of the past experience of the race and of the various different ancestors of the race. Thus considered, common sense will be seen to enshrine something much greater than the opinion of the individual. It may, then, justly demand respectful consideration (though not slavish subjection), as being the expression of the judgment of many generations of men. Nevertheless, the number of vulgar errors is so great that it is obvious we cannot feel any certain conviction about a "common sense' judgment, except under special circumstances, however much we may be disposed-owing to the consideration just mentioned-to accord it a respectful preliminary hearing. Thus no such judgment can be of the least value if it Conditions relates to any matter about which ordinary men would its trustnot at once agree. For an opinion cannot be "common to mankind if the spontaneous judgments of a section of the unreflecting decide against it. It would not invalidate

necessary to

worthiness.