List’s method is essentially that of the pioneer. He was the first to make systematic use of historical comparison as a means of demonstration in political economy. Although he can lay no claim to be the founder of the method, still the brilliant use which he made of it justifies us in classifying him as the equal, if not the superior, of those who at the same moment were attempting the creation of the Historical school and the transformation of history into the essential organon of economic research. List also introduced new and useful points of view into economics. The principle of free exchange as formulated by Smith, and especially by Ricardo and Say, was evidently too absolute and rested upon a demonstration that was too abstract for the ordinary politician. If, as List justly remarks, the practice of commercial nations has so long remained contrary to a doctrine that all economists regard as admirable, it is not without some just cause. As a matter of fact, can the statesman ever place himself outside of the point of view of national interest of which he is the custodian? It is not enough for him to know that the interchange of products will in some degree increase wealth.[615] He must be certain that this increased wealth will benefit his own nation. He must be equally well assured that Free Trade will not result in too sudden a displacement of population or industry, the social and political results of which might be very harmful. In other words, political economy must be subordinated to politics in general, and to-day there is no single economist who does not recognise the impossibility of separating them in practice.[616] There is none that does not perceive the influence of political power on economic prosperity, and that consequently does not recognise the necessity for the different complexion which the peculiar circumstances of each country imposes upon the practical application of the principle of commercial liberty. This is not all. List by abandoning the favourite habit of eighteenth-century writers who contrasted man and society, and by giving us a picture of man as he really is, as a member of a nation, has introduced a fruitful conception into economics of which we have not yet seen the full results. He rightly treats of nations not merely as moral and political associations created by history, but also as economic associations. Just as a nation is politically strengthened by the moral cohesion of its citizens, so its economic cohesion increases the productive energy of each individual and enhances the prosperity of the whole nation.