In Walden and his other mature writings Thoreau often approaches the social problem of poverty not through the directly assertive rhetoric of the Transcendentalist reformers, but by associating certain poor men with the Aristotelian quality of “greatness of soul”. This American, democratic, magnanimous hero lives quietly close to nature, but he is “a prince in disguise”, reincarnating “the worthies of antiquity”, the gods and heroes of classical mythology and history. Walden contains both a sharp awareness of how the Protestant ethic leads to economic hypocrisy in the New Englander's attitude toward the poor and a highly imaginative art of characterization, through which Thoreau transforms the innocent poor into heroes like those of contemporary American romances. But his political essays of the 1850's, particularly those on slavery and the heroic revolutionary activities of John Brown, reveal the limitations of Thoreau's art. His mythopoeic characterization of Brown comes too easily, emerging from a simplistic, abstract, merely polemical response to evil. “Magnanimity” becomes sheer brute force. Thoreau's characters thus lack the dimension of tragic magnanimity; his account of Brown has none of the mysterious innocence of Melville's Billy Budd, whose life and death present striking parallels to Brown's.