Such a list of positive economic principles and practical suggestions should surely give the Greeks some claim to recognition in the field of economic thought. But they should be judged primarily, not by their positive contribution to economic theory or by the practical nature of their suggestions for legislation, but rather by the extent to which they realized the existence of the great economic and social problems, which are still crying for a solution. From this standpoint, we have seen that Plato and Aristotle especially reveal remarkable economic insight. Moreover, there still remains the outstanding fact that the Greeks were the forerunners of the moral, humanitarian, and social emphasis in present-day economy. This alone should give to them a distinct place in the evolution of economic thought, and should make it impossible for Souchon to conclude: “Ces mépris [of G. B. Say] sont pour nous apparaître plus justifiés que les admirations de Roscher.”[1060] The influence of Greek thought upon later economic theory, however, seems not to have been very direct or extensive, probably owing to the incidental nature of their speculation. To be sure, mediaeval economic thought presents, in many respects, an unbroken continuity with the Greek. In their emphasis on the moral, in their doctrines on usury, just price, importance of agriculture, exchange for profit, and in their general conservative attitude toward money and commercial development, mediaeval thinkers are very similar to the Socratics.[1061] Doubtless much of this similarity may be traced to the direct influence of Aristotle, as is especially evident in the work of Thomas Aquinas and Nicholas Oresme.[1062] To a considerable extent, however, the economic ideas of the Middle Ages were a direct outgrowth of the economic and religious conditions under which the writers lived.[1063] In the following centuries, some Greek influence may be traced in Adam Smith, in the physiocrats,[1064] in utopian writers such as More, and in eighteenth-century thinkers like Rousseau.