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 KPISTEMOLOGY

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EPISTEMOLOGY

between -nhat is, and wliat is not comprehensible by us" (I, i, 7), and "to search out the bounds between opinion and knowledge" (I, i, 3). One who reflects on the contradictions among men, and the assurance with which every man maintains his own opinion " may perhaps have reason to suspect that either there is no such thing as truth at all, or that mankind hath no sufficient means to attain a certain knowledge of it" (I, i, 2). This investigation will prevent us from undertaking the study of things that are " beyond the reach of our capacities" (I, i, 4), and will be "a cure of skepticism and idleness" (I, i, 6). Such is the problem; among the main points in its solution may be mentioned the following: " We have the knowledge of our own existence by intuition; of the existence of God by demonstration; and of other things by sensa- tion" (IV, ix, 2). The nature of the soul cannot be known, nor does the trustworthiness of the senses ex- tend to " secondary qualities " ; a fortiori, substance and essences are unknowable. These and other con- clusions, however, are not reached by a truly episte- mological method, i. e. by the criticism of the pro- cesses and postulates of knowledge, but almost exclusively by the psychological method of mental analysis. Following in Locke's footsteps and pro- ceeding farther, Berkeley denied the objectivity even of primary qualities of matter, and Hume held a uni- versal and radical phenomenalism. Aroused from his "dogmatic slumber" by the scepticism of Hume, Kant took up again the same problem of the extent, validity, and limits of human knowledge. This is the task of criticism, not the criticism of books and sys- tems, but of reason itself in the whole range of its powers, and in regard to its ability to attain knowl- edge transcending experience. Briefly stated, the solution reached by Kant is that we know things-as- they-appear, or phenomena, but not the noumena, or thiiigs-in-themselves. These latter, precisely becau.se they are outside the mind, are also outside the possi- bility of knowledge. Kant's successors, identifying the theory of being with the theory of knowing, elab- orated his "Critique" into a system of metaphysics in which the very existence of things-in-theraselveswas denied. After Kant we reach the present period in the evolution of epistemological problems.

Phoble.ms. — To-day epistemology stands in the foreground of philosophical sciences. The preceding outline, however, shows that it was the last to be con- stituted as a distinct investigation and to receive a special systematic treatment. In older philosophers are found partial discussions, not yet co-ordinated and regarding only special aspects of the problem. The problem itself is not formulated before Locke, and no true epistemological solution attempted before Kant. In the beginning of philosophical investigation, as well as in the beginning of cognitive life in the inrli- vidual, knowledge and certitude are accepted as self- evident facts needing no discussion. Full of confidence in its own powers, reason at once rises to the highest metaphysical considerations regarding the nature, es- sential elements, and origin of matter and of the human .soul. But contradiction and conflict of opinions oblige the mind to turn back upon it- self, to reflect in order to compare, test, and per- haps revise its conclusions; for contradictions cause doubt, and doubt leads to reflection on the value of knowledge. Throughout history, also, interest in epistemological questions is aroused chiefly after periods characterized by ontological investigations implying the as.sumption of the validity of knowl- edge. As the psychology of knowledge develops, problems of epistemology grow more numerous, and their solutions more varied. Originally the choice is almost exclusively between affirming the value of knowledge and denying it. For one who looks upon knowledge as a simple fact, these are the only two possible alternatives. After psychology has shown the

complexity of the knowing-process, pointed out its various elements, examined its genesis, and followed its development, knowledge is no longer deemed either valid or invalid in its totality. Certain forms of it may be rejected and others retained; or knowledge may be held as valid up to, but not bej-ond, a certain point. In fact, at present, one would look in vain for absolute and unlimited dogmatism as well as for pure and com- plete scepticism. Opinions vary between these two extremes ; and hence comes, partly at least, the confu- sion of terms by which various views are designated — a labyrinth in which even the most experienced can hardly find their way. Here a few systems only will be mentioned, and their names used in their most general and obvious sense.

The main problems of epistemology may be con- veniently reduced to the following. Starting from the fact of spontaneous certitude, the first question is: Does reflection also justify certitude? Is certain knowledge within man's power? In a general way Dogmatism gives an affirmative, Scepticism a nega- tive answer. Modern Agnosticism (q. v.) attempts to indicate the limits of human knowledge and concludes that the ultimate reality is unknowable. This leads to a second problem: How does knowledge arise, and what modes of knowledge are valid? Empiricism (q. V.) admits no other trustworthy information than the data of experience, while Rationalism (q. v.) claims that reason as a special faculty is more important. A third question presents itself: What is knowledge? Cog- nition is a process within the mind with the special feat- ure of referring to something w ithout the mind, of rep- resenting some extramental reality. What is the value of this representative aspect? Is it merely the result of the mind's inner activity, as Idealism (q. v.) claims? Or is the mind also passive in the act of knowing, and does it in fact reflect some other reality, as Realism asserts? And if there exist such realities, can we know anj^hing about them in addition to the fact of their existence? What is the relation between the idea in the mind and the thing outside the mind? Finally, even if knowledge is valid, the fact of error is undenia- ble; what then will be the criterion by which truth may he distinguished from error? What signs decide whether certitude in any case is justified? Such sys- tems as Intellectualism, Mysticism, Pragmatism, Traditionalism, etc., have attempted to answer these questions in various ways.

Like all other sciences, epistemology should start from self-evident facts, namely the facts of knowledge and certitude. To begin, as Descartes did, with a uni- versal doubt is to do away with the facts instead of interpreting them; nor is it possible consistently to emerge out of such a doubt. Locke's principle that "knowledge is conversant only with our ideas" is con- trary to experience, since in fact it is for the psycholo- gist alone that ideas become objects of knowledge. First to isolate the mind absolutely from external reality, and then to ask how it can nevertheless come into contact with this reality, is to propose an insolu- ble problem. As to the Kantian attitude, it has been criticized repeatedly for examining the validity of know-ledge with the knowing faculty, for making reason its own critic and judge while its rights to criti- cize and jvidge are still held in doubt. Epistemologj', the science of knowing, is closely related to metaphys- ics, the science of being, as its necessary introduction, and as gradually leading into it. The main epistemo- logical issues cannot be met without stepping almost immediately on metaphysical ground, since the faculty of knowledge cannot be examined apart from its exer- cise and therefore from the contents of knowledge. Logic in its strict sense is the science of the laws of thought; it is concerned with the form, not the matter of knowledge, and in this it differs from epistemology. Psycliologj' deals with knowledge as a mental fact, apart from its truth or falsity; it endeavours to deter-