> We all sometimes have a tendency to talk about the things we know jack about

Why not participate in the norm of stating the source of your claims. It's easy enough to start a sentence with "I read in the Guardian" or "If I remember correctly" or "I heard from a professor once".

It even helps just to share your credence in your claim, e.g. "I suspect this is true", or "I'm pretty sure this is how something works".