Page:Catholic Encyclopedia, volume 8.djvu/753

 KNOWLEDGE

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KNOWLEDGE

Knowledge, being a primitive fact of conscious- ness, cannot, strictly spealving, be defined; but the direct and spontaneous consciousness of knowing may be made clearer by pointing out its essential and dis- tinctive characteristics. It will be useful first to con- sider briefly the current uses of the verb "to know". To say that I know a certain man may mean simply that I have met him, and recognize him when I meet him again. This implies the permanence of a mental image enabling me to discern this man from all others. Sometimes, also, more than the mere familiarity with external features is implied. To know a man may mean to know his character, his inner and deeper qualities, and hence to expect him to act in a certain way under certain circumstances. The man who as- serts that he knows an occurrence to be a fact means that he is so certain of it as to have no doubt concern- ing its reality. A pupil knows his lesson when he has mastered it and is able to recite it, and this, as the case may be, requires either mere retention in memory, or also, in addition to this retention, the intellectual work of understanding. A science is known when its principles, methods, and conclusions are understood, and the various facts and laws referring to it co-or- dinated and explained. These various meanings may be reduced to two classes, one referring chiefly to sense-knowledge and to the recognition of particular experiences, the other referring chiefly to the under- standing of general laws and principles. This distinc- tion is expressed in many languages by the use of two different verbs — by yvCivm and elSivai., in Greek; by cogrwscere and scire, in Latin, and by their derivatives in the Romance languages ; in German by kennen and missen.

I. Essentials of Knowledge. — (1) Knowledge is essentially the consciousness of an object, i. e. of any thing, fact, or principle belonging to the physical, mental, or metaphysical order, that may in any man- ner be reached by cognitive faculties. An event, a material substance, a man, a geometrical theorem, a mental process, the immortality of the soul, the exis- tence and nature of Gotl, may be so many objects of knowledge. Thus knowledge impUes the antithesis of a knowing subject and a known object. It al- ways possesses an objective character, and any process that may be conceived as merely subjective is not a cognitive process. Any attempt to reduce the object to a purely subjective experience could result only in destroying the fact itself of knowledge, whichimpliesthe object, or not-self, as clearlyas itdoes the subject, or self.

(2) Knowledge supposes a judgment, explicit or im- plicit. Apprehension, that is, the mental conception of a simple present object, is generally numbered among the cognitive processes, yet, of itself, it is not in the strict sense knowledge, liut only its starting- point. Properly speaking, we know only when we compare, identify, discriminate, connect; and these processes, equivalent to judgments, are found im- plicitly even in ordinary sense-perception. A few judgments are reached immediately, but by far the greater number require patient investigation. The mind is not merely passive in knowing, not a mirror or sensitized plate, in which objects picture themselves; it is also active in looking for conditions and causes, and in building up science out of the materials which it receives from experience. Thus observation and thought are two essential factors in knowledge.

(3) Truth and certitude are conditions of knowledge. A man may mistake error for truth and give his un- reserved assent to a false statement. He may then be imder the irresistible illusion that he knows, and sub- jectively the process is the same as that of knowledge; but an essential condition is lacking, namely, con- formity of thought with reality, so that there we have only the appearance of knowledge. On the other hand, as long as any serious doubt remains in his mind, a man cannot sav that he knows. " I think so " is far

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from meaning "I know it is so"; knowledge is not mere opinion or probable assent. The distinction be- tween knowledge and belief is more difficult to draw, owing chiefly to the vague meaning of the latter term. Sometimes behef refers to assent without certitude, and denotes the attitude of the mind especially in re- gard to matters that are not governed by strict and uniform laws like those of the physical world, but de- pend on many complex factors and circumstances, as happens in human affairs. I know that water will freeze when it reaches a certain temperature; I be- lieve that a man is fit for a certain office, or that the reforms endorsed by one political party will be more beneficial than those advocated by another. Some- times, also, both belief and knowledge imply certitude, and denote states of mental assurance of the truth. But in belief the evidence is more obscure and indis- tinct than in knowledge, either because the grounds on which the assent rests are not so clear, or because the evidence is not personal, but based on the testimony of witnesses, or again because, in addition to the ob- jective evidence which draws the assent, there are subjective conditions that predispose to it. Belief seems to depend on a great many influences, emotions, interests, surroundings, etc., besides the convincing reasons for which assent is given to truth. Faith is based on the testimony of someone else — God or man, according as we speak of Divine or of human faith. If the authority on which it rests has all the required guarantees, faith gives the certitude of the fact, the knowledge that it is true; but, of itself, it does not give the intrinsic evidence why it is so.

II. Kinds of Knowledge. — (1) It is impossible that all the knowledge a man has acquired should be at once present in consciousness. The greater part, in fact all of it with the exception of the few thoughts actually present in the mind, is stored up in the form of latent dispositions which enable the mind to recall it when wanted. Hence we may distinguish actual from habitual knowledge. The latter extends to what- ever is preserved in memory and is capable of being recalled at will. This capacity of being recalled may require several experiences; a science is not always known after it has been masteretl once, for even then it may be forgotten. By habitual knowledge is meant knowledge in readiness to come back to consciousness, and it is clear that it may have different degrees of perfection.

(2) The distinction between knowledge as recogni- tion and knowledge as understanding has already been noted. In the same connexion may be mentioned the distinction between particular knowledge, or knowl- edge of facts and individuals, and general knowledge, or knowledge of laws and classes. The former deals with the concrete, the latter with the abstract.

(3) According to the process by which it is ac- quired, knowledge is intuitive and immediate or dis- cursive and mediate. The former comes from the direct sense-perception, or the direct mental intuition of the truth of a proposition, based as it were on its own merits. The latter consists in the recognition of the truth of a proposition by seeing its connexion with another already known to be true. The self-evident proposition is of such a nature as to be immediately clear to the mind. No one who understands the terms can fail to know that two and two are four, or that the whole is greater than any one of its parts. But most human knowledge is acquiretl progressively. Induc- tive knowledge starts from self-evident facts, and rises to laws and causes. Deductive knowledge proceeds from general self-evident propositions in order to dis- cover their particular application. In both cases the process may be long, difficult, and complex. One may liave to be satisfied with negative conception and analogical evidence, and, as a result, knowledge will be less clear, less certain, and more Uable to error. (See Deduction; Induction.)