Why does someone choose to follow the black arts? King James asks this very question, and answers it as follows: “Curiositie in great ingines: thrist of revenge, for some tortes deeply apprehended: or greedie appetite of geare, caused through great pouerty. As to the first of these, Curiosity, it is onelie the inticement of Magiciens, or Necromanciers: and the other two are the allureres of the Sorcerers, or Witches.” Greed and the thirst for revenge can be found in a scene of low comedy in Macbeth, when the first witch tells the story of how she asked a “rump-fed ronyon” (1.3.5), the wife of a sailor, to give her some chestnuts; when the fat munching woman refused, the witch sailed in a sieve to Aleppo, where she drained the woman's husband dry, infected him with sleeplessness; finally, the first witch displays the treasure of her voyage, “a pilot's thumb” (1.3.28).

The tale of the rump-fed ronyon offers rich insight into the operation of magic, as Shakespeare understood it. First, it establishes the motivelessness of the witches’ malignity: they are happy to destroy a man because his wife was stingy with her snacks—or, in the case of Macbeth, for even less cause, it seems. Second, it establishes that the witches’ special expertise lies in the domain of insomnia: those whom they curse wither away from lack of sleep, from loss of the boundary between vigilance and dream; their lives become a waking hallucination. Third, this tale establishes the narrative tenor of witches’ stories: they sound like tales told by idiots. “They went to sea in a sieve, they did… . And they bought a pig, and some green jackdaws, / And a lovely monkey with lollypop paws,” Edward Lear wrote in “The Jumblies” (1871); similarly, the first witch goes to sea in a sieve, and assembles her tale out of nonsensically disconnected items, such as an eyelid, a chestnut, a compass card, and a stray thumb. As we’ve seen, the sieve is part of the sorcerer's batterie de cuisine, generating random distributions for purposes of divination.