What is a market? What is a limited market? What is an illimitable market? A market, as we have already seen in substance, is nothing in the world but certain _persons_ somewhere with return-services in their hands desirous to part with these in order to get, that is, to buy, some other services offered in exchange. Each set of services is equally a market in relation to the other set. _A market is always persons having something in their hands to sell._ Buyers and sellers are equally a market in relation to each other. Whenever anybody goes forth to buy, he must of course take with him something with which to pay for what he wants to buy, that is to say, he must become a seller the very instant he becomes a buyer; and whenever anybody wants to sell something, he must of course want something already in the hands of somebody else, in which to take his pay, that is, he becomes a buyer the moment he becomes a seller. This helps us to see perfectly what a market is. Defined in the terms of persons, _a market is two men, each glad to get the product of the other, and to render in return his own product_; defined in the terms of things, _a market for products is products in market_. Now, what can limit the universal market for material products? Clearly, it can only be limited either in the element of _Desires_ or in the element of _Return-Services_. But the desires of all men, even of one man, which the efforts of other men may satisfy, have never yet come to a stand-still. Who ever heard of even one man, who was in possession of all the products of all kinds, that he wanted? Even if there were one such man somewhere, there are millions upon millions of other men, whose desires for products such as the efforts of other men can furnish are unlimited in number and infinite in degree. It is not possible, therefore, that there should be a lack of human desires anywhere, that could put any bound to the production of commodities or hinder in the least its ever-swelling march.