CHAPTER XXII.
THE PRINCIPLE OF EVIDENCE
216. Among the principles which, by their pretensions to the title of fundamental, have most figured in the schools, is one called the principle of the Cartesians: "whatever is contained in the clear and distinct idea of any thing, may be affirmed of it with all certainty." We have already seen Kant resuscitate this principle, although in other words, equivocally taking it as synonymous with that of contradiction. Upon close examination we shall easily perceive that the formula of the Cartesians, like that of Kant, only expresses the legitimacy of the criterion of evidence. Both may be simplified to this: evidence is a criterion of truth; or, whatever is evident is true. As we shall hereafter use this transformation to distinguish ideas which we consider very confused, we will show the reason of the equality of the two expressions.
217. To say that any thing is contained in the clear and distinct idea of another thing, is the same as to say that there is evidence that a predicate belongs to a subject; the words have, and can have, no other meaning. To be contained in a clear and distinct idea, is equivalent to seeing one thing in another by that intellectual light which we call evidence; therefore, this expression, "whatever is contained in the clear and distinct idea of any thing," is exactly equivalent to this, "whatever is evident."
To say, that any thing may be affirmed of another with all certainty, is the same as to say, "this thing is true, and we may be perfectly certain of it." It is the truth that is affirmed, and the truth only; therefore, this expression, "may be affirmed of it with all certainty," is exactly equivalent to this, "it is true."
Thus the expression of the Cartesians may be transformed into this: "Whatever is evident is true," or its equivalent, "evidence is a sure criterion of truth."
218. "A predicate that is opposed to a subject does not belong to it," is Kant's formula. The opposition here meant is that founded on ideas, when the predicate is necessarily excluded by intrinsic opposition from the idea of the subject. The expression, then, "a predicate that is opposed to a subject," is equivalent to this: "when the predicate is clearly seen excluded from the idea of the subject," which last is in its turn equivalent to this: "the exclusion, or the opposition between the subject and the predicate, is evident."
"Does not belong to it," means the same as, "it is true that it does not belong to it;" and since these formulas have two values, one for affirmative, another for negative cases, if we say the predicate that is opposed to a subject does not belong to it, we may with equal reason say, the predicate contained in the idea of a subject belongs to it; wherefore, Kant's formula exactly coincides with this: "whatever is evident is true."
219. This transformation gives us greater simplicity and generality; simplicity by the very expression, and generality, because affirmative as well as negative cases are included. The words, "whatever is evident," embrace affirmations as well as negations, for the inclusion of a predicate in a subject may be just as evident as their mutual opposition. Thus, we may see one thing contained in the idea of another, just as we may see it excluded from that idea. Under all conceptions the formula, "whatever is evident is true," is preferable; and if we would express it not as a principle, but as a rule to be applied, it may be converted into this: "evidence is a sure criterion of truth."
220. This transformation must not be supposed to be the only object of the preceding analysis; although in these matters clearness and precision should be carried to the highest possible point, we should nevertheless have abstained from these considerations, had we only proposed to make an innovation, and one perhaps of little practical consequence; the same thing is expressed in both formulas, and he who does not understand the first will not understand the second. Our principal object was not, however, to make this innovation, but to show into what a confusion of ideas those fall who inquire whether the principle involving the legitimacy of the criterion of evidence ought, or ought not, to be considered as fundamental, and be preferred to the principle of contradiction, as also to that of Descartes.
221. We begin by establishing a proposition which may seem a most strange paradox, but is far from being so: the principle of evidence is not evident.
Demonstration.– This principle in its simplest form is this: the evident is true. This proposition, we say, is not evident. When is a proposition evident? When we see the predicate in the idea of the subject; and here this does not occur. Evident is the same thing as clearly seen, as offered to the intellect in a most lucid manner. True is the same as conformity of the idea with the object. We now ask, can you, however much you analyze this idea, "seen with clearness," ever find this other, "conformed to the object?" No. This is an immense leap: we pass from subjectiveness to objectiveness; we affirm subjective to be the reflex of objective conditions; we go from the idea to its object, and this transition is the most transcendental, difficult, and obscure problem of philosophy. Let the reader now decide if we had not ground to assert that the proposition, "the principle of evidence is not evident," was not a paradox.
222. What, then, shall we say of this proposition: "Whatever is evident is true?" It is not an axiom, for the predicate is not contained in the idea of the subject; it is not a demonstrable proposition, for all demonstration rests on evident principles, and consists in deducing from them a consequence evidently connected with them; this cannot take place unless we presuppose the legitimacy of evidence, that is to say, that which is the object of the demonstration. At the commencement of the argument, it might be asked, how do you know the principle on which your argument is based? How do you know it to be true? By evidence. But recollect you are proving that whatever is evident is true, and, therefore, you beg the question. The truth of the laws of logic, to which every argument must conform, is known only by evidence; therefore if we do not suppose whatever is evident to be true, we cannot argue at all.
223. We hold then that the principle of evidence can be based on no other principle, and that, consequently, it has the first mark of the fundamental principle. If it fails, all other principles, – that of contradiction, known like the others only by evidence, included, – fail with it; this is another mark of the fundamental principle. Let us see if it has the third, by aid of which, whoever denies the rest may be refuted.
Rarely does any one deny the principle of contradiction, and admit that of evidence; yet, making this extravagant supposition, this principle alone would be of avail, because the question would be reduced to this: does he admit the principles to be evident? If he does not, his intellect is unlike that of other men; if he does, the argument brought against him is conclusive. You admit that whatever is evident is true; such or such a principle is evident for you, therefore it is true. The premises are evident of themselves; the legitimacy of the consequence is also evident; and he must consequently admit it, since he admits the criterion of evidence to be a general rule.
224. Whence then the singularity we have noticed in this principle? It is neither evident, nor demonstrable; it is necessary to all others, and whoever denies them is refuted by it. Whence, then, such a singularity? It has a very simple cause; it is, that the principle of evidence expresses no objective truth, and therefore is not demonstrable: it is not a simple fact of consciousness, for it expresses the relation of the subject to the object, for which reason it cannot be limited to the purely subjective; it is a proposition known by a reflex act, and it expresses the primary law of all our objective cognitions. These are founded on evidence; this we experience: but when the mind asks why we trust evidence, we can make no other answer than that whatever is evident is true. What is the foundation of this proposition? Ordinarily it has none; we conform to it without ever thinking of it; but if we take the pains to reflect, we find three motives for assenting to it: the first is an irresistible instinct of nature; the second is the destruction of all our cognitions and the impossibility of thought, if we do not admit the legitimacy of the criterion; the third is the perceiving that, admitting this criterion, every thing is co-ordinated in the intellect, that an ideal universe admirably harmonized, takes the place of chaos, and that we feel possessed of the means necessary to reason and to construct a scientific edifice in the real universe, the knowledge of which we have from experience.(22)
CHAPTER XXIII.
THE CRITERION OF CONSCIOUSNESS
225. Having established the worth of the principles of consciousness, of evidence, and of contradiction, in relation to the dignity of fundamental, we will now examine the intrinsic value of the different criteria. And here the doctrine of the preceding chapters, of which the following are the development and complement, furnishes much light. We will begin with consciousness, or the internal sense.
The testimony of consciousness includes all phenomena, either actively or passively, realized in our soul. It is by its nature purely subjective; so that in itself considered, apart from the intellectual instinct and the light of evidence, it testifies nothing with respect to objects. By it we know what we experience, not what is; we perceive the phenomenon, not the reality; what authorizes us to say: such a thing appears to me; but not, such a thing is.
The transition from subject to object, from the idea representing to the thing represented, from the impression to the cause impressing, belongs to other criteria: consciousness is limited to the interior, or rather, to itself, which is nothing but an act of our soul.
226. We must distinguish between direct and reflex consciousness: the former accompanies every internal phenomenon; the latter does not: the former is natural; the latter philosophical: the former abstracts the act of reason; the latter is one of these acts.
Direct consciousness is the presence of the phenomenon to the mind, whether that phenomenon be a sensation or an idea, an act or an impression, in the intellectual or the moral order.
This distinction shows that direct consciousness accompanies every exercise, whether active or passive, of the faculties of our soul. It is a contradiction to say that these phenomena exist in the soul, and are not present to it.
These phenomena are not modifications like those which occur in insensible things; we here treat of living modifications, so to speak, in a living being; in the idea of these modifications is contained their presence to the mind.
It is impossible for us to have a sensation without experiencing it; for whoever says he has a sensation, says that he experiences a sensation: this experience is its presence; an experienced sensation is a present sensation.
Thought is by its essence, a representation that can neither exist nor be conceived without presence; the name itself shows this, and the idea which we join with it confirms the meaning of the word. When we speak of representation, we understand that there is some real or imaginary object, which mediately or immediately offers itself to the subject. There is then presence in every representation, and consequently in every thought.
If, from what is passive, like sensations and representations, we pass to the active, that is, to the phenomena when the soul freely evolves its force in the intellectual or moral order, in combining or willing, this presence is, if possible, yet more evident. The being that thus acts, does not obey a natural impulse, but motives which it proposes to itself, and to which it may or may not attend. To make intellectual combinations and to exercise acts of the will, without either being present to the soul, are contradictory assertions.
227. Reflex consciousness, called by the French aperception, from the verb s'apercevoir, and denoting perception of the perception, is the act whereby the mind explicitly knows any phenomenon which is realized in it. Thus, I hear a noise: the simple sensation, present to and affecting my mind, constitutes what we have called direct consciousness; but if besides hearing, I also aperceive, to use a Gallicism, that I hear; then I not only hear, but also think that I hear: this we call reflex consciousness.
228. It is clear from this example, that direct and reflex consciousness are not only distinct but separable. I may hear without thinking that I hear; and this is very often the case.
229. Most men have little reflex consciousness, and the greatest intellectual force operates directly. This ideological fact is connected with moral truths of the utmost importance. The human mind was not born to contemplate itself, to think that it thinks: its affections were not given as an object of reflection, but as impulses which elevate it to what it is called to: the principal object of its intelligence and love is, in this life as in the other, the infinite being. The worship of itself is an aberration of pride; its punishment is darkness.
230. All great scientific discoveries lie in the objective, not in the subjective order. The exact sciences, natural as well as moral, have emanated not from reflexion of the subject upon itself, but from knowledge of objects and their relations. Even the metaphysical sciences, in all that is most solid in them, ontology, cosmology, and theology, are purely objective: ideology and psychology which consider the subject, are full of the obscurity inherent in all that is subjective; ideology scarcely does more than merely observe internal phenomena, – an observation, we may remark, generally very defective, poorly made, and bewildered with vain cavils; and what has psychology itself, truly demonstrated, except the simplicity of the soul, the necessary consequence of the unity of consciousness? In all else it resembles ideology, and to a certain point, is confounded with it; it observes phenomena, and afterwards defines and classifies them better or worse, but fails to explain their mysterious nature.
231. Consciousness is the foundation of the other criteria, not as a proposition which serves as their basis, but as a fact which is a necessary condition of them all.
232. Consciousness tells us that we see the idea of one thing contained in the idea of another: thus far there is nothing but appearance; the formula, to express its testimony would be: it appears to me; which denotes a purely subjective phenomenon. But this phenomenon is accompanied by an intellectual instinct, an irresistible impulse of nature, which makes us assent to the truth of the relation, not only so far as it is in us, but as it is formed without us, in the purely objective order, whether in the sphere of reality or possibility. Thus it is explained how evidence is founded on consciousness, not as identified with it, but as resting upon it as a fact from which it cannot be abstracted, and as also containing the intellectual instinct which makes us believe whatever is evident to be true.
233. Sensation, in itself considered, is a fact of pure consciousness, since it is immanent in us: so far is it from being an act whereby the mind passes beyond itself, translates itself to the object, that it ought rather to be regarded as a passion than an action, and this accords with the common mode of speaking, which ascribes it to a passive rather than to an active faculty. Nevertheless on this mere fact of consciousness is in some sense founded what is called the testimony of the senses, and consequently all knowledge of the external world, its properties, and relations.
In the sensation whereby we see the sun, there are two things: the sensation itself, that is, the representation which I experience in myself, and which I call sight; and the correspondence of this sensation to the external object which I call the sun. Evidently, these are two very distinct things, and yet we always unite them. Consciousness is certainly the first basis of the formation of judgment; but alone it does not suffice, for it only testifies that the sensation is, not what it is. How is the judgment completed? By means of a natural instinct which makes us render sensations objective, that is, makes us believe in an external object corresponding to the internal phenomena. Thus the testimony of the senses is in some manner founded on consciousness; it does not, however, proceed from consciousness alone, but requires the natural instinct, by means of which we form our judgments in perfect security.
234. We must here remark that evidence has nothing to do with the testimony of the senses, even in their intellectual part, wherein we judge that an external object corresponds to the sensation. The idea of the existence or possibility of an external object does not enter into the idea of the sensation as purely subjective, and without this indispensable condition there can be no evidence. Not only is this clear of itself, but it is confirmed by daily experience. We continually have the representation of the external subjectively considered, as a pure phenomenon in our soul, although no real object corresponds to it; more or less clear when we are awake, but most vivid, even so as to produce a perfect illusion, when we are asleep.
235. With this exposition, the value and extent of consciousness may be exactly determined: this we shall see in the following propositions, in all of which, we would observe, we treat only of direct consciousness.
FIRST PROPOSITION.
The testimony of consciousness extends to all the phenomena that are realized in our soul, regarded as an intellectual and sensitive being.
SECOND PROPOSITION.
236. If there exist in our soul phenomena of a different order, that is to say, if it may in some sense be modified in non-representative faculties, the testimony of consciousness does not extend to such phenomena.
We do not advance this proposition without a solid reason. It is probable, and even very probable, that our soul has active faculties, of the exercise of which it is not conscious; otherwise how explain the mysteries of organic life? The soul is united to the body, and is for it the vital principle, the separation from which causes death, manifested in complete disorganization and decomposition. This activity is exercised without consciousness, either of the mode or of the fact of its existence.
It may be said that there is here a series of those confused perceptions of which Leibnitz speaks in his Monadologie; or that these perceptions are so slight, so wan, as to leave no trace in the memory, nor be an object of reflection: but these are only conjectures. It is hard to persuade one's self that the fœtus in the mother's womb has any consciousness of the activity exercised for the development of its organization: it is also hard to persuade one's self that even in adults there is any consciousness of that same activity producing circulation of the blood, nutrition, and other phenomena which constitute life. If these phenomena are produced, as they certainly are, by the soul, there is in it, an exercise of activity of which it either has no consciousness, or one so weak and confused that it is as if it were not.
THIRD PROPOSITION.
237. The testimony of consciousness, in itself considered, is so limited to the purely internal, that it is of itself worth nothing in the external order, either for the criterion of evidence or that of the senses.
FOURTH PROPOSITION.
The testimony of consciousness is the foundation of the other criteria, inasmuch as it is a fact which they all require, and without which they are impossible.
FIFTH PROPOSITION.
238. From the combination of consciousness with intellectual instinct arise all the other criteria.(23)