The opinion of Locke cited, which occurs at the end of his essay, may be taken as the consummation and final generalization of his theory of knowledge. In the body of the work the conclusion reached by him is, that the elements of all knowledge are ideas (by which is meant what are now commonly called notions or concepts), and that "knowledge [is] but the perception of the connection and agreement, or disagreement, or repugnancy of any of our ideas" (Essay, b. 4, c. 1). This definition, it will be observed, is too narrow, as it excludes the knowledge derived directly from the perception of concrete objects. But allowing for this defect it is accurate and profound and must be taken as the foundation of all science. In the beginning it seems that Locke had no conception, or at least a very inadequate conception of the intimate connection between language and thought, and of the indispensability of the former as an instrument of thought. But as he proceeded he seems gradually to have realized this great truth, which is treated of in his third book; and upon the conclusions thus reached is based his theory of knowledge and his general philosophy as developed in his fourth book, and as generalized in the concluding chapter, to which we have referred. His theory of knowledge, therefore, is to be regarded as based to a great extent expressly, and otherwise implicitly, upon the notion that all knowledge beyond that coming from experience consists in the perception of the agreement, or disagreement, of our ideas, or notions; and hence that all reasoning must consist in the comparison of notions or concepts; that practically this can be effected only by means of the names of the concepts or notions; and hence that Logic must consist in Analysis and Synthesis of names or terms; which is the theory of this work. (See observation of Horne Tooke, Appendix A.) INDEX Abstract and concrete terms, 37 Accent, fallacy of, 203 Accident and genus distinguished, 49 Accident and secundum quid, relation between, 210 Accident, fallacy of, 207, 208 Adjectives regarded as substantives, 36 Amphiboly, 201 Analysis and synthesis, logical and physical, distinguished, 108 Analytical processes, 42 Apodictic, 23, 70 Apprehension, 41 A priori, and empirical notions, 71 Arguing in circle, 160 Aristotle, his dictum, 76; his classification of fallacies, 197 Bain, an opinion of, 83 Burden of proof, 164 Canons of the several figures of syllogism, 100 Categories and predicables distinguished, 66 Classification, division and, 44 Collective and distributive interpretation, 60 Commonplace and original thought distinguished, 112 The numbers refer to sections. Concrete terms, abstract and, 37 Confusion, fallacy of, 139 Connotation and denotation of terms, 32 Consequent, fallacy of the, 212 Consequentis, F., 212 Contradiction, the law of, 125 Contradictory, substitution of, 80 Contraposition, conversion by, 80 Conversion by intension, 58 Conversion of propositions, 54, 70, 91 Conversions, material and formal, distinguished, 92 Copula, the, 55 Criticism, 115 Definition, vocal, 43; nominal or real, 48 Denotation and connotation of terms, 32 Dialectic, 23, 70 Dichotomy, 47 Dictum, Aristotle's, 76; forms of, 99; applicable to all fig- Division, 46 Division and classification, 44 Enthymemes, 105 Equational theory of predication, 56 Equivalence of terms, 78 Equivocation, fallacy of, 127, 191, 201 Essence of term, 49 Euclid, his fifth proposition reduced to syllogisms, 84 Excluded middle, the law of, 125 Extension and intension of terms, 34 The numbers refer to sections. |