Among the structural elements in the plots of folk tales identified by Vladimir Propp are the hero being assigned a difficult task, passing an ordeal, vanquishing rivals, undergoing a change of status, marrying a princess and ascending a throne. Another Propp (no relation), William Propp, a professor of history and Judaic studies, finds these elements in the story of the Exodus. He begins by explaining that the biblical narrative is more complicated than many folk tales given that it has three heroes — Moses, Israel and Yahweh. With reference to the elements just mentioned he writes on page 34: