Euripides, though markedly individualistic, like the Sophists, shows traces of the older use of nature to explain the necessity of the state. He draws a parallel between the social order and the order of nature, by which law and government are justified, and the right of the middle class of farmers to rule is upheld.[51] He emphasizes the importance of agriculture, and the dignity of the peasant farmer (αὐτουργός), who works his own land, as the stay of the country.[52] This latter accords well with his cosmopolitan spirit, which he shares with the Sophists. He opposes the artificial distinctions of birth,[53] slavery,[54] and the traditional Greek idea of the inferiority of woman.[55] His attitude toward wealth is that of the moral philosopher rather than that of the Sophist.[56] Thucydides reveals considerable insight into economic problems, though he does not deal with them directly. Roscher declares that the Greek historian contributed as much as any other writer to give him the elements of his science, since he alone, of all Greek writers, did not confuse his economic ideas with ethics.[57] He recognizes the place of labor in production, and the importance of material wealth as the basis for all higher development.[58] He also has some appreciation of the true nature of capital. In his description of the undeveloped condition of early Greece, which lived from hand to mouth, he writes like a modern economist describing primitive conditions in Europe in contrast to the capitalism of his own day.[59] Cornford’s attempt[60] to discredit Thucydides as a historian, and to show that he missed the true cause, economic, of the Peloponnesian War, is not convincing. Cornford both exaggerates the influence of commercial interests in fifth-century Athens and belittles the economic insight of Thucydides. The Greek writer is, however, like Herodotus, a historical source for the actual economic conditions in Greece, rather than an economic theorist.