Knowledge, as displayed in reactions to environment, 17 ff. perceptual, 58 ff. behaviourist view of, 88 ff. difference between introspective and other, 215 _a priori_, 249 f. limitations on, imposed by structure of language, 264 f. Knowledge-reaction, 216, 282 Language, as a bodily habit, 43 ff. psychological side of, 48 words in an ideal logical, 256 f. and things, relation between, 264 Laws, causal, 144 ff. evidence for, 147 universal characteristics of, 149 Learning, laws of, 23, 29 ff. two ways of, 39 in infants, 41, 48 by increase of sensitivity, 95 f. Leibniz, 239, 241 f. _Le Problème logique de l’induction_ (Jean Nicod), 269, 273 Locke, 244 ff. Logic, 263, 296 “Logical atomism”, 248 Mach, 214, 292 Man, his relation to the Universe, 292, 295, 298 ff. Materialism, as a philosophy, 159 _Mathematical Theory of Relativity_ (Eddington), 283 Matter, the structure of the atom, 98 ff. essence of, 146 f. as conceived in modern physics, 157, 293 old view of, now untenable, 158 ff. constructed out of events, 278 permanence of, only approximate, 279 possibly a structure of mental units, 290 Maxwell’s equations, 107, 145 Meaning, 52, 71, 82 Meinong, 202 Memory, behaviourist theory of, 71 ff. its reference to the past, 188 ff. feeling of pastness complex, 190 more fundamental than imagination, 190 vital difference between imagination and, 194 Dr. Broad’s view on reference to the past, 195 stages of, 195 ff. immediate, 196 f. true recollection, 197 ff. trustworthiness of, 199 Memory and testimony, 5 ff. Mendeleev, 99 “Mental” events, 114, 141 f., 280 f. “Mental” occurrences, 201, 212 _Mentality of Apes_ (Köhler), 37 ff., 62 Mill, J. S., his canons of induction, 269 f. Mind and matter, conventional notions of, 141 distinction between, illusory, 142, 201 gap between, how filled in, 148 interaction between, 150 theory of “neutral monism”, 206 ff. Cartesian dualism, 239 Leibniz’s theory of, 241 Mind, a cross-section in a stream of physical causation, 150 modern conception of, 280 ff. emergent from events, 284 definitions of a, 285 ff. Minkowski, 239 _Mneme_ (Semon), 49 “Mnemic” effects, 49, 209, 295 “Mnemic” occurrences, 49, 180 f. Monads, 241 Monists and pluralists, controversy between, 251 ff. pluralism the view of science and common sense, 253 Moore, Dr. G. E., on notion of “good”, 230 “Moral issues”, 227 Motion, 119, 163 Mystics, 229, 264, 300 Names, 53 Necessity, anthropomorphic notion of, 115, 117 “Neutral monism”, theory of, 206 ff., 210, 282, 292 Newton, 242 Nisbet, R. H., on probability, 275 Object, what happens when we see an, 146 f. Objective and subjective study, 30 Objectivity, 154 f., 169 Ogden and Richards, Messrs., 52