As an example, consider the doctrine of transubstantiation. Are the elements of the sacrament flesh and blood ‘only in a tropical sense’ or are they literally just that? Now “we have no conception of wine except what may enter into a belief either, (1) that this, that, or the other is wine, or (2) that wine possesses certain properties. Such beliefs are nothing but self-notifications that we should, upon occasion, act in regard to such things as we believe to be wine according to the qualities which we believe wine to possess. The occasion of such action would be some sensible perception, the motive of it to produce some sensible result. Thus our action has exclusive reference to what affects our senses, our habit has the same bearing as our action, our belief the same as our habit, our conception the same as our belief; and we can consequently mean nothing by wine but what has certain effects, direct or indirect, upon the senses; and to talk of something as having all the sensible characters of wine, yet being in reality blood, is senseless jargon…. Our idea of anything is our idea of its sensible effects; and if we fancy that we have any other, we deceive ourselves, and mistake a mere sensation accompanying the thought for a part of the thought itself”.
“It appears, then, that the rule for attaining … clearness of apprehension is as follows: Consider what effects, which might conceivably have practical bearings, we conceive the object of our conception to have. Then, our conception of these effects is the whole of our conception of the object”. (Italics mine).
An application of this method to a conception which particularly concerns logic occupies the last section of the article,—a use of the method to make clear our conception of “reality”. Considering clearness in the sense of familiarity, no idea could be clearer than this, for everyone uses it with perfect confidence. Clearness in the sense of definition is only slightly more difficult,—“we may define the real as that whose characters are independent of what anybody may think them to be”. But however satisfactory this is as a definition, it does not by any means make our idea of reality perfectly clear. “Here, then, let us apply our rules. According to them, reality, like every other quality, consists in the peculiar sensible effects which things partaking of it produce. The only effect which real things have is to cause belief, for all the sensations which they excite emerge into consciousness in the form of beliefs. The question therefore is, how is true belief (or belief in the real) distinguished from false belief (belief in fiction)”. Briefly this may be answered by saying that the true belief is the one which will be arrived at after a complete examination of all the evidence. “That opinion which is fated to be ultimately agreed to by all who investigate, is what we mean by the truth, and the object represented in this opinion is the real.” (Note: “Fate means merely that which is sure to come true, and can nohow be avoided”.) The real thus depends indeed upon what is ultimately thought about it, but not upon what any particular person thinks about it. This is clearly brought out in contrast to non-scientific investigation, where personal equation counts for a great deal more. “It is hard to convince a follower of the a priori method by adducing facts; but show him that an opinion that he is defending is inconsistent with what he has laid down elsewhere, and he will be very apt to retract it. These minds do not seem to believe that disputation is ever to cease; they seem to think that the opinion which is natural for one man is not so for another, and that belief will, consequently, never be settled. In contenting themselves with fixing their own opinions by a method which would lead another man to a different result, they betray their feeble hold upon the conception of what truth is. On the other hand, all the followers of science are fully persuaded that the processes of investigation, if only pushed far enough, will give one certain solution to every question to which they can be applied. One man may investigate the velocity of light by studying the transits of Venus and the aberration of the stars; another by the opposition of Mars and eclipses of Jupiter’s satellites; a third by the method of Fizian…. They may at first obtain different results, but as each perfects his method and his processes, the results will move steadily together toward a destined center. So with all scientific research. Different minds may set out with the most antagonistic views, but the process of investigation carries them by a force outside of themselves to one and the same conclusion”. This conclusion, to be sure, may be long postponed, and might indeed be preceded by a false belief which should be accepted universally. But “the opinion which would finally result from investigation does not depend on how anybody may actually think…. The reality of that which is real does depend on the real fact that the investigation is destined to lead, at last, if continued long enough, to a belief in it”.
It will be seen that this article does not intend to put forward any new theory of truth. It is simply an attempt at expounding a new theory of clearness. Peirce desires to describe a new way of clearing up metaphysical disputes, the method, namely, of finding the meaning of each question by reducing it to its experimental consequences.
For Peirce a doctrine could be perfectly clear and yet false. This would be the case where one had a vivid idea of all the outcomes in experience involved by the idea, but yet was unable to prophesy any outcome that should be verified by future fact. Our idea of the object would not in that case ‘correspond to the reality’ in the sense of giving us a belief which could be ‘verified by all investigators’.
Peirce, then, instead of having a radical and startling theory of truth to propose, would consider himself an ultra-conservative on the question of what shall be called truth. Approaching the matter from the standpoint of a scientist, (for he says in another connection that he had at this time spent most of his life in a laboratory), he is concerned only with an attempt to apply “the fruitful methods of science” to “the barren field of metaphysics”. For metaphysics seems to him very much in need of outside help. His different conception of the two disciplines may be seen from the following passage. In contrast to philosophy, he is eulogizing the natural sciences, “where investigators, instead of condemning each the work of the others as misdirected from beginning to end, co-operate, stand upon one another’s shoulders, and multiply incontestable results; where every observation is repeated, and isolated observations count for little; where every hypothesis that merits attention is subjected to severe but fair examination, and only after the predictions to which it leads have been remarkably borne out by experience is trusted at all, and then only provisionally; where a radically false step is rarely taken, even the most faulty of those theories which gain credence being true in their main experiential predictions”.
It is in a desire to elevate metaphysics to somewhere near this level that Peirce proposes his new theory of clearness, believing that much of the useless disputation of philosophy, as he sees it, will end when we know exactly what we are talking about according to this test.
On the question of truth he might indeed have referred to another of his early articles, where the same idea of the independence of truth from individual opinion is brought out. The much-quoted paper on “How To Make Our Ideas Clear” was, as we have noted, the second of a series called “Illustrations of the Logic of Science”. In order to get his doctrine of truth more adequately before us, we may turn for a moment to the first article of the series, the paper called “The Fixation of Belief”.
Here Peirce begins by pointing out four methods for fixing belief. In the first, or ‘method of tenacity’, one simply picks out the belief which for some reason he desires, and holds to it by closing his eyes to all evidence pointing the other way. The second, or the ‘method of authority’, is the same except that the individual is replaced by the state. The third, or ‘a priori method’, makes a thing true when it is ‘agreeable to reason’. But this sort of truth varies between persons, for what is agreeable to reason is more or less a matter of taste.
In contrast with these, and especially with the a priori method, a method must be discovered which will determine truth entirely apart from individual opinion. This is the method of science. That is, “To satisfy our doubt … it is necessary that a method should be found by which our beliefs may be caused by nothing human, but by some external permanency—by something upon which our thinking has no effect…. It must be something which affects, or might affect, every man. And, though these affections are necessarily as various as are individual conditions, yet the method must be such that the ultimate conclusion of every man shall be the same. Such is the method of science. Its fundamental hypothesis, restated in more familiar language, is this: There are real things whose characters are entirely independent of our opinions about them; those realities affect our senses according to regular laws, and, though our sensations are as different as our relations to the objects, yet, by taking advantage of the laws of perception, we can ascertain by reasoning how things really are, and any man, if he have sufficient experience, and reason enough about it, will be led to one true conclusion. The new conception here involved is that of reality. It may be asked how I know that there are any realities. If this hypothesis is the sole support of my method of inquiry, my method of inquiry must not be used to support my hypothesis. The reply is this: 1. If investigation cannot be regarded as proving that there are real things, it at least does not lead to a contrary conclusion; but the method and conception on which it is based remain ever in harmony. No doubts of the method, therefore, arise with its practice, as is the case with all the others. 2. The feeling which gives rise to any method of fixing belief is a dissatisfaction at two repugnant propositions. But here already is a vague concession that there is some one thing to which a proposition should conform…. Nobody, therefore, can really doubt that there are realities, or, if he did, doubt would not be a source of dissatisfaction. The hypothesis, therefore, is one which every mind admits. So that the social impulse does not cause me to doubt it. 3. Everybody uses the scientific method about a great many things, and only ceases to use it when he does not know how to apply it. 4. Experience of the method has not led me to doubt it, but, on the contrary, scientific investigation has had the most wonderful triumphs in the way of settling opinion. These afford the explanation of my not doubting the method or the hypothesis which it supposes”. (p.12)