[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. μ. 1078b 28 sqq.
[7] Cf. Arist. Top. θ. i. 1 ad fin.
[8] For whom see Dümmler, Antisthenica (1882, reprinted in his Kleine Schriften, 1901).
[9] Aristotle, Metaphys. 1024b 32 sqq.