Of contributions towards the history of special periods or schools of logical thought the list, from the opening chapters of Ramus's _Scholae Dialecticae_ (1569) downwards (v. Rabus _loc. cit._) would be endless. What is of value in the earlier works has now been absorbed. The _System der Logik_ (1828) of Bachmann (a Kantian logician of distinction) contains a historical survey (pp. 569-644), as does the _Denklehre_ (1822) of van Calker (allied in thought to Fries) pp. 12 sqq.; Eberstein's _Geschichte der Logik und Metaphysik bei den Deutschen von Leibniz bis auf gegenwärtige Zeit_ (latest edition, 1799) is still of importance in regard to logicians of the school of Wolff and the origines of Kant's logical thought. Hoffmann, the editor and disciple of von Baader, published _Grundzüge einer Geschichte der Begriffe der Logik in Deutschland von Kant bis Baader_ (1851). Wallace's prolegomena and notes to his _Logic of Hegel_ (1874, revised and augmented 1892-1894) are of use for the history and terminology, as well as the theory. Riehl's article entitled _Logik in Die Kultur der Gegenwart_, vi. 1. _Systematische Philosophie_ (1907), is excellent, and touches on quite modern developments. Liard, _Les Logiciens Anglais Contemporains_ (5th ed., 1907), deals only with the 19th-century inductive and formal-symbolic logicians down to Jevons, to whom the book was originally dedicated. Venn's _Symbolic Logic_ (1881) gave a careful history and bibliography of that development. The history of the more recent changes is as yet to be found only in the form of unshaped material in the pages of review and _Jahresbericht_. (H. W. B.*) FOOTNOTES: [1] Cf. Heidel, "The Logic of the Pre-Socratic Philosophy," in Dewey's _Studies in Logical Theory_ (Chicago, 1903). [2] Heraclitus, _Fragmm._ 107 (Diels, _Fragmente der Vorsokratiker_) and 2, on which see Burnet, _Early Greek Philosophy_, p. 153 note (ed. 2). [3] e.g. Diog. Laërt. ix. 25, from the lost _Sophistes_ of Aristotle. [4] _Plato and Platonism_, p. 24. [5] Nothing is. If anything is, it cannot be known. If anything is known it cannot be communicated. [6] _Metaphys. [mu]. 1078b_ 28 sqq. [7] Cf. Arist. _Top. [theta]_. i. 1 _ad fin_. [8] For whom see Dümmler, _Antisthenica_ (1882, reprinted in his _Kleine Schriften_, 1901). [9] Aristotle, _Metaphys._ 1024b 32 sqq. [10] Plato, _Theaetetus_, 201 E. sqq., where, however, Antisthenes is not named, and the reference to him is sometimes doubted. But cf. Aristotle, _Met._ H 3. 1043b 24-28. [11] Diog. Laërt. ii. 107. [12] Aristotle, _An. Pr._ i. 31, 46a 32 sqq.; cf. 91b 12 sqq. [13] Athenaeus ii. 59c. See Usener, _Organisation der wissenschaftl. Arbeit_ (1884; reprinted in his _Vorträge und Aufsätze_, 1907).