In Book V of Plato's Republic, Socrates and Glaucon establish that men and women have different natures. However, they had previously established that different natures must follow different ways of life. Taken together, these two statements imply that men and women should live differently. Yet Socrates had shown that men and women should share the same mode of life. Hence Socrates asks Glaucon, "We've agreed that different natures must follow different ways of life and that the natures of men and women are different. But now we say that those different natures must follow the same way of life. Isn't that the accusation brought against us?" (Grube, 127). Socrates and Glaucon have found an apparent contradiction in their argument, so they set out to find their error.
Subsequently, Socrates points out that they never determined the ways in which men and women are different. After some discussion, Socrates says to Glaucon, "Women share by nature in every way of life just as men do, but in all of them women are weaker than men" (Grube, 129). The difference between men and women, according to Socrates, is not a difference in natures. Rather, the distinction is one of degrees. Men and women are essentially the same, but men tend to be stronger.
Consequently, Socrates concludes that women should have a share in the management of the city because women have the same fundamental nature that men have. In the callipolis, everyone contributes according to his or her nature, and so women and men have corresponding roles in the city. Their natures are essentially the same, so their roles must correspond as well.
Looking back with modern prejudices, Socrates may not go as far as we would wish in defending women's equality. However, Socrates offers a remarkably equitable view when compared with his contemporaries. In the mytho-poetic tradition, the story of Pandora highlights womankind as the source of human troubles. Hesiod treats women as necessary evils needed for the reproduction of the race. Later, following both Socrates and Plato, Aristotle would deny Socrates' assertion that men and women have the same nature. For him, women are by nature inferior to men. Hence Socrates appears progressive when judged by the standards of his own culture.