Maybe ... but many facts aren''t.
We know, for instance, that oxygen and nitrogen exist. We know that Genghis Khan rampaged across Asia, and his descendants rampaged across Europe and the Middle East. We know that Hitler backstabbed Stalin during Operation Barbarossa, etc.
We don't know for sure what Hannibal was thinking in the aftermath of the battle of Cannae, but we
do know that he crossed the Alps with his elephants. It's mentioned in many of the classical texts. =)
Many facts are, well, factual. They happened. We shouldn't deny them just because it suits us to. =(