"Go, my son! Fight, make your way in the world." But — the proviso is implicit — tell no one who or what you are.

Ushimatsu Segawa, the protagonist of Toson Shimazaki's 1906 novel "Hakai" ("The Broken Commandment"), harbors a deep, dark secret: who and what he is. His true self is very different from his apparent self. His person and his persona are separate and incompatible. The Ushimatsu his friends know is a personable, intelligent young man, an able and popular rural primary school teacher. The Ushimatsu his friends don't know is an eta — a member of a traditional underclass whose name means, roughly, "filth."

It's a designation with roots deep in ancient Shinto notions of purity. Buddhism, a more philosophical and compassionate religion, unfortunately had its own notions of purity, and the eta, hereditary slaughterers, tanners and executioners, found themselves twice damned when Buddhism came to Japan in the sixth century. Official emancipation from opprobrium came in 1871. But unofficial opprobrium raged on.