When it comes down to it, what are being traded in a capitalist economy are property rights -- the ownership rights in goods and services. Trade and exchange will be minimal without reasonably secure property rights. And it is these trades and exchanges (supply and demand) that determine free-market prices. Prices in a capitalistic economy reflect the relative scarcity of a good or service as well as the amount and intensity of consumer demand. Free-market prices are the only viable means of a rational economic calculation. If a good or service becomes in shorter supply, for whatever reason, its price will rise, all other things being equal. The higher price will give consumers the proper incentive to do what is needed whenever anything becomes scarcer: conserve, or cut back on consumption. At the same time, the higher price gives producers an incentive to supply more to the market (since it is more profitable to do so), while others are given financial incentives to create and market substitutes for the higher-priced item.
— Thomas DiLorenzo; How Capitalism Saved America