294 THE GENERAL THEORY OF EMPLOYMENT bk. v

ment and expectations concerning the future affectwhat we do to-day. It is when we have made thistransition that the peculiar properties of money as alink between the present and the future must enterinto our calculations. But, although the theory ofshifting equilibrium must necessarily be pursued interms of a monetary economy, it remains a theory ofvalue and distribution and not a separate “theory ofmoney”. Money in its significant attributes is, aboveall, a subtle device for linking the present to the future;and we cannot even begin to discuss the effect of chang-ing expectations on current activities except in monetaryterms. We cannot get rid of money even by abolishinggold and silver and legal tender instruments. So longas there exists any durable asset, it is capable of possess-ing monetary attributes 1 and, therefore, of giving riseto the characteristic problems of a monetary economy.

ii

In a single industry its particular price-level de-pends partly on the rate of remuneration of the factorsof production which enter into its marginal cost, andpartly on the scale of output. There is no reason tomodify this conclusion when we pass to industry as awhole. The general price-level depends partly on therate of remuneration of the factors of production whichenter into marginal cost and partly on the scale of out-put as a whole, i.e. (taking equipment and technique asgiven) on the volume of employment. It is true that,when we pass to output as a whole, the costs of pro-duction in any industry partly depend on the output ofother industries. But the more significant change, ofwhich we have to take account, is the effect of changesin demand both on costs and on volume. It is on theside of demand that we have to introduce quite newideas when we are dealing with demand as a whole and

1 Cf. Chapter 17 above.