Note 162 — X (continued 3)

The conservative function of valuation may be further illustrated by reference to the well-known principle of marginal utility of which we have already made mention (p. 307 above), and which has played so great a part in modern economic theory. The value of the unit quantity of a stock of any commodity is, according to this principle, measured by the least important single use in the schedule of uses to which the stock as a whole is to be applied. Manifestly, then, adherence to this valuation placed upon the unit quantity is in so far conservative of the whole schedule and the marginal value is a "short-hand" symbol expressive of the value of the whole complex purpose presented in the schedule. Moreover, the increase of marginal value concurrently with diminution of the stock through consumption, loss, or reapplication is not indicative so much of a change of purpose as of determination to adhere to so much of the original program of consumption as may still be possible of attainment with the depleted supply of the commodity.