AUTHORITIES.--J. Bergmann, _Reine Logik_ (Berlin, 1879); _Die Grundprobleme der Logik_ (2nd ed., Berlin, 1895); B. Bosanquet, _Logic_ (Oxford, 1888); _The Essentials of Logic_ (London, 1895); F. H. Bradley, _The Principles of Logic_ (London, 1883); F. Brentano, _Psychologie vom empirischen Standpunkte_ (Vienna, 1874); R. F. Clarke, _Logic_ (London, 1889); W. L. Davidson, _The Logic of Definition_ (London, 1885); E. Dühring, _Logik und Wissenschaftstheorie_ (Leipzig, 1878); B. Erdmann, _Logik_ (Halle, 1892); T. Fowler, _Bacon's Novum Organum_, edited, with introduction, notes, &c. (2nd ed., Oxford, 1889); T. H. Green, _Lectures on Logic_, in _Works_, vol. iii. (London, 1886); J. G. Hibben, _Inductive Logic_ (Edinburgh and London, 1896); F. Hillebrand, _Die neuen Theorien der kategorischen Schlüsse_ (Vienna, 1891); L. T. Hobhouse, _The Theory of Knowledge_ (London, 1896); H. Hughes, _The Theory of Inference_ (London, 1894); E. Husserl, _Logische Untersuchungen_ (Halle, 1891, 1901); W. Jerusalem, _Die Urtheilsfunction_ (Vienna and Leipzig, 1895); W. Stanley Jevons, _The Principles of Science_ (3rd ed., London, 1879); _Studies in Deductive Logic_ (London, 1880); H. W. B. Joseph, _Introduction to Logic_ (1906); E. E. Constance Jones, _Elements of Logic_ (Edinburgh, 1890); G. H. Joyce, _Principles of Logic_ (1908); J. N. Keynes, _Studies and Exercises in Formal Logic_ (2nd ed., London, 1887); F. A. Lange, _Logische Studien_ (2nd ed., Leipzig, 1894); T. Lipps, _Grundzüge der Logik_ (Hamburg and Leipzig, 1893); R. H. Lotze, _Logik_ (2nd ed., Leipzig, 1881, English translation edited by B. Bosanquet, Oxford, 1884); _Grundzüge der Logik (Diktate)_ (3rd ed., Leipzig, 1891, English translation by G. T. Ladd, Boston, 1887); Werner Luthe, _Beiträge zur Logik_ (Berlin, 1872, 1877); Members of Johns Hopkins University, _Studies in Logic_ (edited by C. S. Peirce, Boston, 1883); J. B. Meyer, _Ueberweg's System der Logik_, fünfte vermehrte Auflage (Bonn, 1882); Max Müller, _Science of Thought_ (London, 1887); Carveth Read, _On the Theory of Logic_ (London, 1878); _Logic, Deductive and Inductive_ (2nd ed., London, 1901); E. Schröder, _Vorlesungen über die Algebra der Logik_ (Leipzig, 1890, 1891, 1895); W. Schuppe, _Erkenntnistheoretische Logik_ (Bonn, 1878); _Grundriss der Erkenntnistheorie und Logik_ (Berlin, 1894); R. Shute, _A Discourse on Truth_ (London, 1877); Alfred Sidgwick, _Fallacies_ (London, 1883); _The Use of Words in Reasoning_ (London, 1901); C. Sigwart, _Logik_ (2nd ed., Freiburg-i.-Br. and Leipzig, 1889-1893, English translation by Helen Dendy, London, 1895); K. Uphues, _Grundlehren der Logik_ (Breslau, 1883); J. Veitch, _Institutes of Logic_ (Edinburgh and London, 1885); J. Venn, _Symbolic Logic_ (2nd ed., London, 1894); _The Principles of Empirical or Inductive Logic_ (London, 1889); J. Volkelt, _Erfahren und Denken_ (Hamburg and Leipzig, 1886); T.