The mythical demigod Theseus is a testament to the heroic ideal of the ancient Greeks. King of the Athenians, his mythical slaying of the minotaur is still present in the western cultural narrative.

If you’ve ever watched a werewolf movie, you already know the drill: someone yells “silver,” a weapon appears, and the monster suddenly has a very bad evening. That idea shows up so often that it can ...