Welcome to misinformation on the Internet!
If YOU don’t know, and someone is confident in their answer, you can’t possibly know if they know for sure or not.
And when someone else who DOES know disagrees, how do you know which one is lying? You don’t! You can only go by who SOUNDS more right, and that is often manipulated by what you wanted to believe before the conversation even started!
I imagine language with some new tags.
Tags like “original source” and “number of iterations from original source”
(“Iterations” probably isn’t the right term. If Bob saw it, then Bob told Sally, then Sally told Frank. Frank has “3rd iteration” knowledge. But what’s the better term?)
Some Australian and Papua New Guinean Languages have this feature.
Just like spanish marks tense in its verbs, these languages have to alter the form of the verb depending on the level of “firsthandedness” of the thing they describe. Sometimes, this isnt even optional