“You have no idea what you’re talking about” is a funny phrase. After all, everybody has *some* idea about what they’re talking about. The idea might be misinformed or inaccurate but it’s still *some* idea, however wrong or incoherent. Interesting how imprecise we are about this

See also “you haven’t got a clue”. I mean, you surely have *some* clues. Possibly the wrong clues. If we are to make progress on any discussion we ought to seek to share our respective inventories of clues

“You’re an idiot” is another fun one, to which I’m like, yes, you get me! Please help me