An Essay on Economics - Anarchism Series Karl Marx

Conversely: if the price of a commodity falls below its cost of production, then capital will be withdrawn from the production of this commodity. Except in the case of a branch of industry which has become obsolete and is therefore doomed to disappear, the production of such a commodity (that is, its supply), will, owning to this flight of capital, continue to decrease until it corresponds to the demand, and the price of the commodity rises again to the level of its cost of production; or, rather, until the supply has fallen below the demand and its price has risen above its cost of production, for the current price of a commodity is always either above or below its cost of production

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