Asking sincerely “where did you hear that” can sometimes get people to realise that they are just repeating a myth though, it should never be “I bet you can’t source that :smuglord:” but instead a “let’s go through and examine this claim together”. People get defensive when they feel they or their ideas are being attacked, but framing it as a “let’s explore and learn together” has a lot more success than “You’re wrong about that.” which will almost always be interpreted negatively, treated as a personal attack.