If, however, as may very well happen—not in the case of potatoes probably, but in large articles of limited consumption—there is no such circle of demand at lower levels, what will happen is that the farmer will dismiss half the hired labour, produce the same quantity of potatoes as before, and maintain the former high price. For farmers, like other business men, do not put themselves on “salaries,” and give the public the benefit of all cheapening of production. It is characteristic of the capitalist employer in all departments that he speculates on having a profit, and thinks no profit too high, just because, as a speculative gain, it may be balanced any year by as great a loss. It is contrary, then, to all experience to think that employers will voluntarily reduce prices—any more than they will voluntarily raise wage or pay higher interest—because costs have decreased. They only do so under the compulsion of fear that their rivals will cut the feet from under them. Where competition is active, it will often seem as if reduction of costs were almost immediately followed by fall in prices of products; but, in the last resort—and that is what concerns us in seeking for a universal law of value—the new prices are determined by the lower and wider levels of want which are ready to take up increased supply of the majority of ordinary commodities. Transfer the argument now to the production of iron. If new mines are opened, the first phenomenon is not a fall in the price of iron, but an increase of supply. If the demand from the side of iron wares has hitherto been met at the price—as we must assume—the new extra supply will not be taken off at the price, and there is, for the moment, over-supply. At this point, the lower level of demand for iron wares hitherto unsatisfied asserts itself, and offers its subjective valuation. This is accepted: a new marginal employment is found for iron. The price of this marginal product now determines the price of the productive good iron; and in time it is possible for competition to impose this marginal value on all iron products, and the price of iron wares generally falls.