Louis F. Post,
The basic facts of economics
(1927)
“ Trade is an essential part of the Productive Process in Economics. It is inseparable from Labor specialization. If some Labor be devoted to the Production of one kind of Artificial Objects, one kind of Wealth—food, for instance—the producers of such Wealth must satisfy their desires by trading with other kinds of Labor specialists—clothing producers, for instance—for what the latter make and the former do not make. Evidently, then, the more minutely Labor takes on specialized activities, the more extensive and intensive must Trade become. ”
