ART. I. -- WHAT IS MEANT BY THE ULTIMATE CRITERION OF CERTITUDE.
18. The principle of certitude is the motive which produces the adhesion of the intellect to a known truth. -- Every cognitive faculty attains to a knowledge of the truth in regard to its proper object. But truth, properly speaking, resides solely in the intellect, which adheres firmly to a truth only by reason of some motive. This motive is called the principle or criterion of this certitude. That principle on which all the others depend is the ultimate criterion of certitude. It is with this principle only that the present chapter is concerned.
19. The principle of certitude is twofold, intrinsic and extrinsic. -- The intellect adheres to a proposition either because the intrinsic truth of the proposition is in itself manifest, or because an extrinsic motive produces conviction, though the intellect does not perceive the truth of the proposition in itself. In the former case the principle of certitude is intrinsic; in the latter, it is extrinsic.
ART. II. -- THE INTRINSIC PRINCIPLE OF CERTITUDE.
20. The intrinsic principle of certitude is the objective evidence of the thing. -- That which causes the intellect to know the truth of an entity is that the entity manifests itself to the intellect. But that which produces in us the knowledge of truth also produces certitude, since certitude is only the state of the intellect consequent on the possession of its proper object; in other words, it is the repose of the intellect in the possession of truth to which it firmly adheres. The intrinsic principle of certitude, therefore, is the entity itself as manifesting itself to the intellect and determining its adhesion. This manifestation of the entity to the intellect is what is called objective evidence. This evidence is immediate, or evidence of intuition, when the thing becomes manifest to the intellect immediately and by its own light; as, "The whole is greater than any one of its parts," "The sun is shining;" it is mediate, or evidence of deduction, when it becomes manifest only after some mental process, and by means of another truth.
21. Huet bases all certitude on revelation; La Mennais, on the authority of the common consent of mankind, or common sense; Reid and the Sentimentalist school, on instinct and internal sentiment; Descartes, on the clear and distinct idea of an object; Leibnitz and Arnauld, on the principle of contradiction; Cousin, on the impersonality of reason; Galluppi, on the testimony of consciousness; Kant, on practical reason; Rosmini, on the idea of possible being; Gioberti and the Ontologists, on the intuition of the divine essence, or on the intuition of the divine ideas. All these systems must be rejected as erroneous. -- If, with Huet (1630-1721), we doubt that which we know by the senses, by consciousness, or by the intellect, and of which we are certain only by the intrinsic evidence of the thing, it is manifest that we must also doubt that which is known to us by divine revelation itself, since we can know what divine revelation teaches only by means of our senses and our intellect.
Our knowledge of the consent of mankind to a truth is obtained through the senses and the intellect; therefore, according to the very principles of La Mennais, we are necessitated to doubt our knowledge of this consent. Besides, mankind is made up of individuals; but, if certitude is impossible to the individual as such, the mere collection of the uncertain cognitions of individuals can never produce certain cognition.
The adhesion of the intellect, as being the state of a rational being, cannot be determined without a motive. But the instinct and internal sentiment of Reid are blind causes which do not make known the motive of adhesion; therefore, they cannot be the principle of human certitude. Instinct is peculiar to the animal and not to an intelligent human being; far from explaining anything, it requires explanation itself.
Descartes regards evidence as the foundation of certitude; but, according to him, evidence consists in the clear idea of the thing, and is purely subjective; that is, it is merely an act of the mind, and not the manifestation of the object to the mind. It is, conseqnently, variable and changing. But the certitude which puts us in possession of truth must proceed from an immutable and objective principle, like truth itself. The clear idea of Descartes, being a pure modification of the cognitive act, cannot be the principle of certitude.{1}
We cannot, with Leibnitz and Arnauld (1612-1694), base certitude on the principle of contradiction; for our assent to this principle must be determined by a motive, and this motive is its intrinsic evidence.
Besides the manifest absurdity that would result from admitting the Impersonal Reason of Cousin and his school, we must remark that this reason, even if supposed to be real, could not produce certitude, unless in virtue of some motive distinct from itself.
We cannot agree with Galluppi (1770-1846) in founding certitude on the testimony of conciousness. For consciousness testifies only to internal acts and states, and is a purely subjective witness; hence it cannot produce certitude regarding objects outside the mind.
The practical reason of Kant must necessarily have speculative reason for its basis; therefore, if the speculative order is uncertain, the practical order will share the same fate.
Rosmini errs in placing the principle of certitude in the idea of possible being; for, aside from the falsity of the innateness of this idea, it cannot produce certitude regarding entities in the real order, since it is purely subjective.
According to Ontologism, the intellect does not form to itself a representation of the object known; hence the ideal order is destroyed, and consequently, all knowledge also. Thus, direct vision of the divine essence or of the divine ideas, far from being the principle of certitude, is the negation of all knowledge and of all certitude.
ART. III. -- THE EXTRINSIC PRINCIPLE OF CERTITUDE.
22. The ultimate extrinsic principle of certitude is the authority of him who affirms the fact.
23. An extrinsic principle or criterion of certitude is either divine or human authority: the latter is mere human authority, if there be question of fact; or the authority of scientists, if there be question of scientific truths; or the authority of common sense, if there be question of the principal truths necessary for our intellectual or moral life.
24. Divine authority or revelation is a perfect criterion of certitude and superior to all others. -- God neither can deceive us nor can be deceived Himself. His infallibility and veracity give us the most perfect certitude regarding the truths which He has revealed to us.
25. Human testimony produces certitude in us when we know that the witnesses cannot be deceived and do not wish to deceive. -- The knowledge and veracity of the witnesses are, therefore, the two essential conditions on which human authority is based.
26. The absolute impossibility of the facts testified to, and in certain cases the improbability of the facts, argue against the validity of the testimony. -- If a fact is absolutely impossible, evidently the testimony borne to it is false. If the fact is improbable, the testimony requires more careful examination. But it is sometimes difficult to determine whether the fact is impossible; hence we should rely mainly on the positive indication of the knowledge and veracity of witnesses.
27. We have a certain indication of the knowledge and veracity of witnesses, when they agree in reporting a fact in the same way. -- The testimony of a single witness does not, of itself, afford a guarantee of truth; but if the witnesses are numerous and if they agree in their testimony, we cannot call their testimony in question; for then we must suppose either that all are deceived in the observation of the same fact, or that they all agree to deceive in reporting the fact. But, on the one hand, it cannot happen that many men should at the same time be subject to the same defect in their senses; and on the other hand, many men cannot maintain the same error in the same way, since a lie is produced by the passions, and the passions vary with individuals.
But if the witnesses report facts humiliating to themselves; if they are very numerous, of different ages and conditions; if they endure torments and even death in support of their testimony; if they report public facts of great importance, which are not contradicted, but rather confirmed by the very persons whom these facts condemn, then their testimony produces perfect certitude. Such is the testimony in support of the facts on which Christianity rests.
The certitude produced by human authority is often only moral, so that its opposite is not absolutely impossible but only against the laws by which the moral world is governed; but cases occur in which it passes into absolute certitude, when the opposite is plainly contradictory; as, for example, when there is question of a matter wherein it belongs to the providence of God to see that no error creep in. The certitude is also absolute when the witnesses are many and could not, if they would, deceive in relating a fact that is important and obvious to the senses of all.
ART. IV. -- MEANS BY WHICH TESTIMONY IS TRANSMITTED.
28. The three means by which human testimony is transmitted are: tradition, history, and monuments. -- Tradition is an oral account transmitted from mouth to mouth. History is a written record of past events. Monuments are all the works of men which may serve as signs of accomplished facts; they comprise pillars, inscriptions, medals, charters, etc. Their testimony is indirect, if they afford knowledge which they were not intended to convey; thus, the magnitude of the pyramids indirectly testifies to the power of the Egyptian kings. It is direct when they make known the fact which they were designed to transmit; thus, the medal commemorative of a victory bears direct testimony to that event.
29. When tradition is continuous, constant, and relates to a public and important fact, it is a source of certitude. -- Contemporaneous witnesses of an event give certain information of it to those who come after them. The latter may weigh the value of the testimony, but they will find deception and error impossible, if the witnesses to the fact are numerous. Hence, they can, in their turn, produce in those who succeed them a certitude equal to their own, and so the knowledge of the events may be carried down to the most remote ages. We thus see the falsity of the opinion of Locke, who holds that a tradition gradually loses its value by the lapse of time. It should be constant or uniform at least in substance and in leading circumstances though it may vary in minor details. The fact should be public and important, attested by many witnesses and brought to the knowledge of many.
30. It is absurd to object against the value of tradition the errors current during many ages among different nations. -- These errors or fables have come down to us devoid of consistency and universality, and destitute of the essential notes of authority; and the fact that it has at all times been easy to show their falsity is a proof that they cannot be confounded with true tradition.
31. Monuments are a source of certitude when we can establish their authenticity. -- A monument testifies that at the time when it is erected, the fact whose memory it is intended to perpetuate is certain and universally believed. It is impossible for a counterfeit fact to be generally believed by those who are its contemporaries. But if it is to make known the truth, evidently the monument must really belong to the epoch to which it is referred, or be erected by a people to whom a constant and well attested tradition of the fact has come down. Doubt as to the authenticity of a monument produces doubt concerning the fact which it attests.
32. History is a source of certitude when it is authentic and entire. -- A historical narrative, when published, is equivalent to a public testimony of its contemporaries. If these receive such a work as truthful, and if it has undergone no alteration in the lapse of ages, it merits equal credence in all times, and is a criterion of certainty.
33. We are certain that a writing is authentic: 1. When, by an unbroken tradition, it is recognized as such; 2. When it is in harmony with the manners and customs of the time to which it is referred, and with the character and the genius of the author to whom it is ascribed; 3. When by its nature it makes imposition impossible. -- If from the epoch to which it is referred a writing has always been recognized by the tradition of the common people or of the learned as the production of a particular author, if the contents of the writing be in harmony with the known customs of the age, and with the life and genius as well as with the style of the author, its authenticity cannot be disputed. For this is especially guaranteed by the moral impossibility of publishing the writing without the immediate discovery of imposture.
34. We are certain that a writing is entire: 1. When its component parts mutually agree both in matter and in form; 2. When the copies which have been made of it in different times and places are identical; 3. When, on account of its importance and the great number of persons interested in it, alteration becomes impossible. -- The intrinsic proof of the integrity of a writing is found in the perfect harmony of the different parts which compose it: the extrinsic proof consists in the identity of the extant copies of the writing, even though made at different times and in different places. Finally, if the writing interests a great number of persons, and if they have never protested against any alteration, the integrity of the work reaches its highest degree of certainty.
35. The veracity of a history is established from the very nature of the writing and from the knowledge and veracity of the writer. -- The intrinsic indications of the veracity of a history are the notoriety of the facts recorded, their importance, and their relation to other facts which occurred at the same time. The knowledge and veracity of the writer are established in accordance with the rules of ordinary testimony. We should examine whether he is unbiassed by passion or prejudice, whether he could easily have ascertained the facts, and especially whether he agrees with other writers recording the same facts. To some extent, these rules apply in examining the veracity of a monument.
36. The objections of Scepticism against the value of historic testimony serve only to establish it more firmly. -- It is objected that many books, once received as authentic, have proved later to be forgeries. But if we have means of detecting the spuriousness of certain writings, evidently the authenticity of others, in which nothing of the kind can be detected, only remains the more firmly established. In like manner, it is true that many copies of ancient works have come down to us with alterations. But if the parts in which these copies do not agree prove that alteration has taken place, the other parts, in which they do agree, prove that the original text has been preserved intact.
ART. V. -- AUTHORITY OF COMMON SENSE AND OF THE LEARNED.
37. By the testimony of common sense is meant the general and constant assent of mankind to some truth. -- To know this general assent, it is not necessary to question all men; it suffices to know the views of enlightened men and the opinion of nations in general.
38. Common sense is a criterion of certitude in regard to the truths to which it bears testimony. -- That men in different times and in different places be unanimous in affirming a thing, it is necessary that this affirmation be founded in nature itself. But that which is the effect of nature cannot deceive; we must, therefore, admit the testimony of common sense.
39. The truths affirmed by common sense are: 1. Principles which are easily known by the use of natural reason; 2. Those moral and religious truths the knowledge of which is necessary to the moral life of man. -- There are both immediate and mediate principles the cognition of which is easy and requires only the natural development of reason: as, "The whole is greater than any of its parts." These principles, therefore, are known by all men. The principal moral and religious truths, however, the knowledge of which is indispensable to man, are not so easily known. But few minds could have attained to them, and even then only after much time, with an intermixture of error, and in an uncertain manner. Consequently, if they are known and accepted by all men, it is in virtue of a primitive revelation made by God to the first man, and handed down to his descendants by unbroken tradition.
40. It is vain to object against the authority of common sense the corruption of primitive traditions among nations in the course of time and the almost universal diffusion of certain errors. -- The alterations produced in primitive traditions are neither constant nor universal; they are then without value. Thus, polytheism was professed only during a certain period among different nations, and it was not universal; therefore it must be attributed to the corruption of men and not to their nature. While admitting the reality of certain errors, like that of the revolution of the sun around the earth, we must also observe that they are rather the result of ignorance; but ignorance should not be confounded with error. Besides, to determine the revolution of the heavenly bodies was beyond the sphere of the commonalty, and therefore beyond the common sense of mankind, of which exclusively is the present question.
41. The authority of the learned in matters relating to their specialties demands our prudent assent. -- The authority of the savant in his peculiar domain, should be respected by the unlearned, since he who by the culture of his mind is fitted to apprehend a truth may impose it on him who could not of himself attain to its knowledge. But as the learned themselves are competent to examine the particular truths in question, they should judge the authority of other scientists by their own reason. Hence we may formulate the following three rules: 1. The authority of scientists should be accepted so long as there is no reasonable ground to believe it false or to suspect it; it should be rejected, if it is known to be false; 2. Every scientist is a competent judge only in the science of which he is master; 3. One scientist may accept the affirmations of another, when he cannot himself ascertain their truth or demonstrate their falsity;{2} yet he may reject them if the opposite arguments are of equal weight.
ART. VI. -- IMPORTANCE OF AUTHORITY AS A CRITERION OF CERTITUDE.
42. Authority is necessary for the complete development of our mind and is the source of most of our knowledge. -- Without the aid of authority, man could, indeed, acquire the knowledge of some truths; but, if we except those which are sensible and elementary, they would be very limited and bound up with many errors. Authority develops his mind promptly and without fatigue, enriches it with a store of knowledge which it could never acquire by itself, either on account of its elevation or of the time required for their acquisition or of insurmountable material difficulties. It is because authority is necessary for the normal and complete aevelopment of the intellect, that the mind is naturally inclined to accept authority, especially during the early years of life.
{1} Descartes held, when his faculties were developed, that as much of his knowledge had not been scientifically acquired, he should doubt of everything that was not evidently certain. Though doubting of the veracity of his faculties, he professed to be unable to doubt the principle, "I think, therefore I exist." From this he derived his principle that the criterion of certitude is a clear and distinct idea. Thence he deduced the existence and veracity of God, and consequently the veracity of man's faculties. But his "methodical doubt" is contradictory, since he must rely upon intellect for his fundamental principle. Moreover, he falls into a vicious circle, for from the veracity of his intellect he proves God's existence, and from the existence and veracity of God, he infers the veracity of man's faculties.
{2} For a clear exposition of the harmony between the positive resuits of science and the truths of faith, consult Apologie de la Foi Chrétienne.