Hamilton, Sir W.:  on space, 76;
    on the external world, 174; also, 182;
    reference, 311;
    his dualism, 312;
    on utility of philosophy, 316. 
  Hegel:  his conception of philosophy, 11;
    an objective idealist, 190. 
  Heraclitus:  his doctrine, 4; on the soul, 101. 
  Herodotus:  1-2. 
  History of Philosophy:  much studied, 273-274;
    its importance, 274-281;
    how to read it, 281-287;
    references, 316. 
  Hobhouse:  on theory of knowledge, 248; reference, 312. 
  Hoeffding:  his monism, 200-201; his history of philosophy, 311. 
  Howison:  on pluralism, 205. 
  Humanism:  312-313. 
  Hume:  his doctrine, 170-171;
    use of word “impression,” 177;
    influence on Kant, 177-178. 
  Huxley:  on other minds, 135, 138; on automatism, 308. 
  Hypothetical Realism:  see Realism.

  Idealism:  in Berkeley and Hume, 168-171;
    general discussion of the varieties of, 187-192;
    proper attitude toward, 289-291. 
  Ideas:  distinguished from things, 33-36;
    in psychology, 36-38;
    Berkeley’s use of the word, 168-170;
    Hume’s use of the word, 177. 
  Imagination:  contrasted with sense, 45-49;
    extension of imagined things, 113. 
  Immateriality:  of mind, see Plotinus, and Mind. 
  Impression:  Hume’s use of word, 177. 
  Infinity:  infinity and infinite divisibility of space, 73-80;
    of time, 88-90; also, 95-97;
    mathematics and, 226. 
  Inside:  meaning of word, 55. 
  Interactionism:  see Mind and Body. 
  Intuitionalists; defined, 240. 
  Ionian School:  3.

  James, W.:  on pragmatism, 220-222 and 312-313;
    on psychology and metaphysics, 230-231;
    on interactionism, reference, 308;
    on “free-will,” 309-310. 
  Jevons:  his logic, 224; on study of scientific method, 256. 
  Jodl:  315.

  Kant:  on space, 75;
    his critical philosophy, 175-180;
    his philosophy criticised, 211-218;
    references to, 307, 311. 
  Keynes:  314.

  Localisation:  of sensations, what, 127. 
  Locke, John:  on doubt of external world, 32;
    on substance, 108;
    on perception of external world, 166-168;
    his empiricism, 209-210;
    his attempt at a critical philosophy, 215-216;
    on innate moral principles, 240;
    reference to “Essay,” 310;
    his hypothetical realism, 311;
    treatment of substance, references, 312. 
  Logic; the traditional, 224;
    “modern” logic, 224-225;
    Jevons and Bosanquet referred to, 224-225;
    philosophy and, 225-229;
    compared with arithmetic, 225-227;
    deeper problems of, 227;
    Spencer cited, 228;
    utility of, 264-265;
    references, 314. 
  Lucretius:  his materialistic psychology, 102.