The presumption of a spurious value for the currency, by the force of law expressed in the regulation of prices, contains in itself, however, the seeds of final economic decay, and soon dries up the sources of ultimate supply. If a man is compelled to exchange the fruits of his labors for paper which, as experience soon teaches him, he cannot use to purchase what he requires at a price comparable to that which he has received for his own products, he will keep his produce for himself, dispose of it to his friends and neighbors as a favor, or relax his efforts in producing it. A system of compelling the exchange of commodities at what is not their real relative value not only relaxes production, but leads finally to the waste and inefficiency of barter.