Myself, its about corroboration from reliable sources. Grocery store tabloids aren't as reliable as the NYTimes. But the NYT ain't 100% reliable either. So I corroborate. What's your method?
How do you verify claims- thus knowing its a fact?
Think logically, check Wikipedia and even if my logic and Wikipedia agrees with the claim I will look further checking more sites and compare the info. The info with the least amount of logic behind it and sample size falls under the "false" info which I don't trust.
Even if I do trust the info I classify as "true" I don't take it as absolute truth as it might've been exaggerated or something about it might still be inaccurate to some extend so I think of it as a best info available.
I'll take most claims from mainstream sites that don't have a history of making things up (or where the claim would be against their usual bias) at face value, and check for corroboration on other sites otherwise.
The truth might be that there is no provable truth, just some measure of probability, which is consistent with quantum mechanics and Heisenberg's uncertainty principle, both of which might be highly probable. Or not. You see where this is going...
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