Psychology: psychological knowledge characterized, 25-28; attitude of psychologist toward external world, 36-38; toward mind, 110-111; philosophy and, 230-234; double affiliation of, 234-235; utility of, 268-269; metaphysics and, 313; "rational," 315. Ptolemaic System; 282. Pythagoras: the word "philosopher," 2. Pythagoreans: their doctrine, 4. Qualities of Things: contrasted with sensations, 51-56. Rational Cosmology: 315. Rationalism: the doctrine, 206-209. Rational Psychology: 315. Real: see Reality. Realism: hypothetical realism, 168; "natural" realism, 174; general discussion of realism and its varieties, 181-187; ambiguity of the word, 186-187. Reality: contrasted with appearance, 35; in psychology, 36-38; the "telephone exchange" and, 38 ff.; things and their appearances, 59-61; real things, 61-63; ultimate real things, 63-68; the "Unknowable" as Reality, 68-72; real space, 80-87; real time, 93-99; substance as reality, 111; real and apparent extension, 113-114; measurement of apparent time, 128; Bradley's doctrine of reality, 191-192; Clifford's panpsychism and reality, 197-198. Reflective Thought: its nature, 28-31. Reid, Thomas: doctrine of "common sense," 171-174; references, 310. Religion: philosophy and, 250-254; conceptions of God, 252-253; God and the world, 253-254; see God. Representative Perception: plain man's position, 32-36; the psychologist, 36-38; "telephone exchange" doctrine, 38-44; the true distinction between sensations and things, 45-58; the doctrine of, 165-168; Descartes and Locke quoted, 165-168. Richter, Jean Paul: on the solipsist, 133. Royce: an objective idealist, 311; a monist, 312.