> "So before you go around claiming that serif typefaces are easier to read... It's one of many myths you (and I) have accepted as true, that isn't."
It isn't true? Prove it. Until then, you don't know whether the myth is true, and it is not necessarily a false belief.
The bit you elided said this:
"The embarrassing truth is, there's no solid research to back up that claim."
Shouldn't the burden of proof be the other way around? Otherwise it follows that goblins and fairies aren't necessarily false beliefs.
You could imagine anything and claim it is not necessarily a false belief until someone proves that it is. Worse, you could imagine something with properties such that it is impossible to prove that it doesn't exist. At this point we'd all have to go around accepting your imaginary world of "not necessarily false" beliefs because we can't prove them to be false. What a terribly unstable situation that would be. Imagine, millions of people believing in one not necessarily false set of beliefs, and millions of other people believing in a different set of not necessarily false beliefs, and both groups claiming that the other must be wrong, each without method of proving the other to be false. What a dangerous way to reason about things.
Myths can be true, like, you know, the existence of Nineveh (yes, it was a "Myth" and then it was proved true).
The myth is a false belief because there's no evidence to support it. However, being a false belief doesn't prove the statement false, simply undetermined.