For the rest, it cannot be supposed that the "freedom" thus constituted had much actuality. Sons of soldiers and artisans were held bound to follow their father's profession, as in the hereditary castes of the East,[318] and none of the fruits of freedom are to be traced in Byzantine life. Still, the fact remains that the commercial and industrial life sustained the political, and that the political began definitely to fail when the commercial did. Constantinople could hardly have collapsed as it did before the Crusaders if its commerce had not already begun to dwindle through interception by Venice and the Italian trading cities. As soon as these were able to trade directly with the East they did so, thus withdrawing a large part of the stream of commerce from Byzantium; and when, finally, they acquired the secret of her silk manufacture, her industrial revenue was in turn undermined. On the economic weakening, the political followed; and the Eastern Empire finally fell before the Turks, very much as the Western had fallen before the Goths. FOOTNOTES: [Footnote 233: Aristotle, _Politics_, v, 9.] [Footnote 234: _Id._ i, 2.] [Footnote 235: Plutarch, _Solon_, c. 24.] [Footnote 236: _Id._ c. 22. Cp. Dr. Grundy, _Thucydides and the History of his Age_, 1911, p. 66, as to Solon's evident purpose of promoting manufactures.] [Footnote 237: Maisch, _Manual of Greek Antiquities_, Eng. tr. p. 38. Cp. Meyer, ii, 644.] [Footnote 238: Cp. Cunningham, _Western Civilisation_, i (1898), 100-2.] [Footnote 239: Grote, ii, 504. Hitherto Athens was far behind other cities, as Corinth, in trade. The industrial expansion seems to begin in Solon's time (Plutarch, _Solon_, c. 22; Busolt, _Griechische Geschichte_, i, 501).] [Footnote 240: Busolt, as cited, i, 549-50. The details, many of them from lately recovered inscriptions, are full of interest. Cp. Grote, ii, 462.] [Footnote 241: Plutarch, _Agis._ c. 5; Aristotle, _Politics_, ii, 9; Thirlwall, viii, 133.] [Footnote 242: The arguments of K.O. Müller (Dorians, Eng. tr. b. iii, c. 3, §§ 3-5) in discredit of the received view, though not without weight, have never carried general conviction. Cp. Maisch, _Manual of Greek Antiquities_, Eng. tr. p. 17.] [Footnote 243: See the recovered passage of Polybius (xii, 6, ed. Hultsch) cited (from Mai, _Nov. Collect. Vet. Scriptor._ ii, 384) by Müller (_Dorians_, Eng. tr. ii, 205). Cp. M'Lennan, _Kinship in Ancient Greece_, § 2.]