Fear old women in fairy tales. For as long as people have been telling stories, crones have been scaring the wits out of children. But why does the face of evil so often belong to an old woman?Typecasting is one explanation. “What do we have? Nags, witches, evil stepmothers, cannibals, ogres. It’s quite dreadful,” says Maria Tatar, who teaches a course on folklore and mythology at Harvard. Still, Tatar is quick to point out that old women are also powerful — they’re often the ones who can work magic.