89. Scholastic Philosophy begins, as the Physical Sciences pretend to do, by ascertaining and examining undeniable facts; in this particular it differs strikingly from many false systems in Philosophy which commence with theories directly contradictory to all experience. When entering on the subject of the existence of certainty, we are at once brought face to face with a patent fact which may be stated thus: All men having the full use of reason exhibit a direct and natural adhesion to many truths as objectively certain.
90. We are not yet maintaining that those truths are objectively certain; we are only stating the undeniable fact that all men adhere to them as objectively certain. We call this adhesion direct, i.e., antecedent to reflection and to philosophic analysis. For instance, all men consider their own existence, the existence of bodies, the connection between cause and effect, the difference between right and wrong as objectively certain. (See Balmes's Fundamental Philosophy, cc. 1. 2, 3; Kleutgen's Philosophie, 3d Treatise.) No fact on which any physical science relies is more undeniable. We have called this adhesion natural, because in science we call any effect natural if it is found constantly and universally to attend a given cause. Now, this adhesion is constantly and universally found in man; therefore it must be natural to man.
91. Thesis II. This direct and natural adhesion of all men to many truths as objectively certain is (a) certainty properly so called; (b) not indeed philosophical certainty, but (c) capable of becoming such.
Proof: (a) Certainty properly so called is a firm adhesion to a truth, on account of motives which exclude all fear of error. But the adhesion here spoken of is such; therefore it is certainty properly so called. We prove the minor.
1. It is firm; in fact, man cannot rid himself of it.{1}
2. It excludes fear of error; i.e., we do not mistrust these judgments.
3. This fear of error is excluded by the evidence of the objective truth. As St. Thomas expresses it: "It is the property of first principles that they not only are necessarily true, but also manifest themselves evidently as objectively true." If this fear of error were not excluded by the evidence of the objective truth, it would be excluded either by the free will of man or by a blind necessity compelling man to judge wrongly. But it is not excluded by our will, for we adhere to the truth even against our will. Nor by a blind necessity to judge falsely; for then our intellect would be no intellect at all, since an intellect is a power to see the truth, not a power to act blindly.
(b) This direct adhesion is not itself philosophic certainty; for it is antecedent to reflection and analysis, while phiosophic certainty is subsequent to both.
(c) It is capable of becoming philosophic certainty; for, when reflected on and analyzed, it is distinctly seen to contain motives sufficient to exclude all fear of error, and thus the element is supplied which constitutes the accidental difference between ordinary certainty and philosophic certainty, viz., the distinct perception of the motives for adhesion to truth (No. 85).
92. Objections: 1. This reasoning supposes several things that have not yet been demonstrated; e.g., that we have understanding. Answer. It does not suppose anything that needs demonstration or that could reasonably be doubted.
2. Some judgments in which all men concurred were false; e.g., that the sun moved round the earth. Answer. All men judged that the sun moved around the earth, we distinguish; they judged about the scientific question whether it was the earth's or the sun's motion that caused the phenomena perceived, we deny; few men gave this question any thought, and those who did would naturally judge that the motion appeared to be in the sun. If any judged that it was in the sun, they erred freely. All judged that the sun was seen in different directions successively, we grant. They called that change 'motion,' and so do even the learned to-day, when they speak of the sun as rising and setting, and they distinguish apparent from real motion, relative from absolute motion.
93. The only escape from the thesis just proved is that attempted by the Sceptics, i.e., by those few philosophers who pretend that man can really be certain of nothing. Sceptics are of two kinds: universal or subjective Sceptics, who refuse to admit any certainty at all, even that of their own existence; and partial or objective Sceptics, who admit their own existence and nothing or very little more.
94. Thesis III. The theory of Universal Scepticism is self-contradictory.
Proof. That theory is self-contradictory, which affirms and denies the same thing; but such is the theory of universal Scepticism. Therefore it is self-contradictory. We prove the minor: Scepticism denies that there is any certainty at all; at the same time it implicitly affirms several things as certain; e.g., that certainty is something different from doubt, that the words used have certain meanings, that those using them exist, etc. If the Sceptic should plead that he does not hold even those points as certain, he must then grant that, for all he knows, he may be saying and even meaning just the contrary of what he teaches, which would be an absurd theory; but even this would implicitly affirm that the Sceptic exists, speaks, etc.
95. In connection with Scepticism, we must consider the Methodic Doubt recommended by Descartes, who, under the Latinized name of Cartesius, wrote in the middle of the seventeenth century. He was not a Sceptic; but he traced out a false system of studying the existence of certainty: destroying the solid basis of Philosophy, he substituted for it a weak fabric of his own invention, and left little in the minds of his followers but ruin and confusion. He maintained, (a) That every philosopher should begin his speculations by doubting of everything. (b) Next, the philosopher will find that he cannot help granting the fact of his own thought, and he will conclude from it his own existence: Cogito, ergo sum -"I think, therefore I am." (c) Hence the would-be philosopher will infer the general rule that whatever is clearly perceived is true. (d) Then finding that he clearly perceives the idea of God, he thence concludes to the existence of God. (e) From the veracity of God he infers the reliability of his own faculties. (f) Thence, at last, he reasons to the certainty of his knowledge.
96. Thesis IV. Descartes' Methodic Doubt is absurd.
Proof. That is absurd which affirms and denies the same thing; but the doubt in question does so. For in it the philosopher begins by denying the reliability of reason, and at once implicitly affirms its reliability by using it to prove his own existence: "I think, therefore I am." He pretends to doubt all his faculties, and still he treats the guidance of those same faculties as reliable. Besides, Descartes moves in a vicious circle: he proves the reliability of our faculties by the veracity of God, and the veracity of God by the reliability of our faculties, etc.
97. The error of Sceptics arises from their false supposition that nothing is certain which is not demonstrated by discursive reasoning. Now, the science of Mathematics begins by the admission of axioms which are self-evident; e.g., that "the whole is greater than a part," that "two things equal to a third are equal to each other," etc. The science of Philosophy must follow a similar process: it must draw its first conclusions from premises which are evident without proof. Besides, like Mathematics and all other sciences, it must admit without proof the reliability of the reasoning process. If the first premises and the reliability of reason required proof, man could never make the first start in scientific studies; in fact, he would be incapable of reasoning at all: he would not be a rational being.
98. Every philosopher, therefore, must, on entering the field of science, affirm with certainty: 1. His own existence; called the first fact 2. The principle of contradiction, viz., that a thing cannot 'be and not be' at the same time; called the first principle. 3. The power of the intellect to know truth; called the first condition. These truths are not blindly admitted: they are seen to be objectively evident. There is no alternative between admitting them and admitting the self-contradiction of universal Scepticism.
99. To refute partial Scepticism, we must prove the reliability of the various means by which certainty may be attained, as we shall do in the following chapter. Still, the arguments which we shall adduce will, in many cases, be rather scientific explanations than strict proofs: scientific explanations, because they will show distinctly what causes or reasons we have for firm adhesion to the truths; not strict proofs, because reliability of the means in question is in several cases proved while taking their reliability for granted, as having no need of demonstration.
{1} The sceptic Pyrrho, when laughed at for fleeing from a falling stone with as much earnestness as if he had no doubt of its reality, replied ingenuously: "It is hard entirely to throw off human nature." if any votary of philosophy should begin to have any real doubts of the existence of certainty, he would need rest of mind and healthy exercise of body, not abstract reasoning, to convince him of objective certainty.