Originally Posted by
Quertus
If the books you're reading weren't written by the future people and brought back via Teleport Through Time, or by people asking questions about the future through Divinations, your world is suboptimal.
Color blue to taste.
(I'm not a fan of Knowledge skills. No, I've never made a character whose backstory was that they were reading their own (temporally-displaced) journals as the excuse for their knowledge skills, why do you ask?)
(Quertus, my signature academia mage for whom this account is named, isn't reading books - he's writing them. Much more fun than making knowledge checks, IMO)