symmetrical, 16, 44; transitive, 16, 32 Relatum, 48 Representatives, 120 Rigour, 144 Royce, 80 Section, Dedekindian, 69 ff.; ultimate, 111 Segments, 72, 98 Selections, 117 Sequent, 98 Series, 29 ff.; closed, 103; compact, 66, 93, 100; condensed in itself, 102; Dedekindian, 71, 73, 101; generation of, 41; infinite, 89; perfect, 102, 103; well-ordered, 92, 123 Sheffer, 148 Similarity, of classes, 15 ff.; of relations, 83; of relations, 52 Some, 158 ff. Space, 61, 86, 140 Structure, 60 ff. Sub-classes, 84 ff. Subjects, 142 Subtraction, 87 Successor of a number, 23, 35 Syllogism, 197 Tautology, 203, 205 The, 167, 172 ff. Time, 61, 86, 140 Truth-function, 147 Truth-value, 146 Types, logical, 53, 135 ff., 185, 188 Unreality, 168 Value of a function, 47, 108 Variables, 10, 161, 199 Veblen, 58 Verbs, 141 Weierstrass, 97, 107 Wells, H. G., 114 Whitehead, 64, 76, 107, 119 Wittgenstein, 205 n. Zermelo, 123, 129 Zero, 65 PRINTED IN GREAT BRITAIN BY NEILL AND CO., LTD., EDINBURGH. TRANSCRIBER'S NOTES Minor typographical corrections and presentational changes have been made without comment. This ebook was produced using OCR text generously provided by the University of Toronto through the Internet Archive.