[30] Value and Distribution, pp. 330-31.

[31] "Values, Positive and Relative." Annals, vol. ix.

[32] It is, of course, recognized that exchange modifies value in so far as exchange is a productive process. But the essential thing here is the transfer aspect of exchange, which would hold even in a communistic society where value relations might be found out by some process other than exchange.

[33] Political Economy, New York, 1888, p. 84.

[34] Cours d'Économie Politique, vol. i, pp. 8-9.

[35] Edgeworth, F. Y., Mathematical Psychics, London, 1881, chapter on "Unnumerical Mathematics," pp. 83 et seq.

[36] A fuller discussion of the functions of the value concept is given in chapter xi where this argument is materially strengthened. The points here made, however, seem adequate.

[37] Jevons, Principles of Economics, 1905 (posthumous), p. 50.

[38] Walker, op. cit., p. 5.

[39] Marx, op. cit., vol. i, chap. i.