The article presents the comment of the author on the selection of one of his article related to market economy. In ignoring the machine process by which two hundred million Americans now live, and fastening their attention on "the market," economists of the twentieth century are of course following an ancient tradition. The first economic literature of the Western world was contained in the sermons in which medieval schoolmen sought to identify "just price." They saw no economic significance in the horseshoe, any more than did the blacksmiths who devised the horseshoe. But then, centuries later, Adam Smith, great as he was, completely missed the significance of the industrial revolution of the eighteenth century in England. At the same time the new doctrine found an academic rostrum. Not only has "political economy" produced a formidable body of classics for which students could be held responsible, the discovery was made almost immediately that economic situations, being largely composed of financial transactions expressed in terms of quantities of money, are therefore very readily reduced to sets of equations, which in turn can be reduced to graphs, all of which lends itself most readily and naturally to the exigencies of pedagogy.