Prices also indicate the relative availability of different products, and the cost of producing more of them. Market prices motivate people to respond as if they are as concerned with the interests of others as they are with their own. Of course, it is primarily self-interest that motivates consumers to respond that way, rather than concern for people they will never meet. Indeed, higher prices tell consumers nothing about why cotton products have become more valuable. Market prices are efficient precisely because they do not overload consumers with irrelevant information.
Prices also motivate suppliers to respond to the interests of others.
Obviously, higher prices tell suppliers that consumers want more of a product. Suppliers are strongly motivated to respond appropriately. But consumers also communicate information disagreeable to suppliers when they decide they want less of a product. The prices textile producers, for example, pay for inputs reflect the value consumers place on other products that could be produced with those inputs. If those other products become more valuable to consumers, textile producers will receive this information through higher prices for their inputs, which are bid away by the other industries.