[4] Loc. cit., ch. XVII, p. 100.

[5] Cf. for instance, Plato, Laws, ch. XI, and Aristotle’s Politics, bk. I, ch. 9; Nicomachean Ethics, by Aristotle, bk. V, ch. 5.—Roman authors defined money as a “just medium and measure of commutable things” Moneta est justum medium, et mensura rerum commutabilium, quoted in H. C. Black, Dictionary of Law, p. 785. [1891].

[6] Wealth of Nations, bk. II, ch. II.

[7] Principles of Political Economy and Taxation, ch. XXI.

[8] Principles of Political Economy, bk. III, ch. VII.

[9] Principles of Social Science, vol. II, ch. XXX, 1.

[10] Die Philosophie Heracleitos des Dunkeln, vol. I, p. 22. [1845].

[11] Capital, English ed. part I, ch. III.

[12] The Purchasing Power of Money, ch. II, ces. 1. [New York, 1911].

[13] D. Kinley, Money, a Study of the Theory of the Medium of Exchange, ch. V, 6. [New York, 1913].