You should be women, / And yet your beards forbid me to interpret / That you are so.
Act I, Scene 3 · Banquo
Context
Banquo continues trying to make sense of the witches' appearance, noting the contradiction between their apparent gender and their beards.
Analysis
The word "forbid" carries a legalistic weight, as if the witches' beards don't just confuse Banquo but actively prevent him from categorizing them as women—they violate a rule he can't override. This gender ambiguity destabilizes one of early modern England's most rigid social binaries, making the witches figures of fundamental disorder. By making gender unreadable, Shakespeare signals that the normal markers people use to judge trustworthiness and social position won't work here.
Essay Tip
Use this to argue that the witches represent a collapse of the interpretive frameworks Banquo and Macbeth rely on—when you can't even determine someone's gender, you've lost the ability to "read" them at all, which is why Macbeth proves so vulnerable to misreading their prophecies.