User blog comment:Madman97/The Jyggalag Theory and the Elder Scrolls/@comment-25109952-20130811115139/@comment-11345660-20130817001032

Jyggalag has written down everything that has ever happened and will happen BEFORE the Daedra cursed him. The assumption that Jyggalag was weak for a couple thousand years is sound, but memory loss? I rather doubt it. If he remembers each time he changes from Sheogorath to Jyggalag why he is what he is and tries each time to take over the Shivering Isles, then there is no reason to assume he doesn't remember how he got to that point. The Daedra cursed him to be the thing he hated, not take his knowledge away from him. They turned him into a madman because it was the thing he hated most, his duel opposite. Sheogorath still retains great power and is able to outsmart his fellow daedra with ease, so Jyggalag must have some power as well.

The pen doesn't need to apply to Jyggalag if he was the on who wrote the Elder Scrolls. I agree that even he is subject to its whims, but for the actions of everyone it doesn't matter. Actions are documented with the pen, thus the sword and the pen are the exact same thing for the Elder Scrolls.