talk through your hat
Meaning: If you're talking through your hat, you're talking about something without knowing much about it, or you claim something is true when it isn't.
- Evan says that quantum physics proves that space and time don't really exist, but Kathy says he's talking through his hat.
- I proved that George was talking through his hat by checking on the internet to find out if what he said is true - and it isn't.
Our biology teacher says evolution is a fact, and that people who say it isn't real are talking through their hats. He says these people