Oh wait, you're right, I thought it was the same since Spartoi was able to get into the original via the copy. But I guess it was the witches' powers that made it possible because only the text's were the same?

And there's reason why the copy even exists if it doesn't have powers, then you could read what contains in the book of Eibon, but then without the feeling of 'stopping thinking'. Was that also possible with only HOLDING the book?(as I read in the recap) Because it doesn't make sense when Noah uses it to attack.

IRL it could be that if you know too much or everything, it would get boring, but still it is hard for people to get to that right? Even in the SE universe, why is having all knowledge dangerous when it's nearly impossible to come to that? There can't be suddenly a character popping out and say:'Hey! I got the reason of life and now I'm going insane durrrrrr'.
Besides, knowledge is something you could use more in a positive way, especially in a plot. Thanks to knowledge there is understanding and developement and such, it could even be used as the antipole or weapon against the insanity. Because if you choose to stay dumb and don't think(knowledge also lets you think), you won't be able to handle new problems and enemies. It is thanks to knowledge that Shinigami, Stein, Kid & the rest came to that theory that too much knowledge if dangerous for you,,,,yeah.

And I suspect Kid's powerups are at Shinigami's costs. Remember previous chapter when Kid did that thing with the parent's seven rays? There was a panel wherein Shinigami suddenly became down or something and Spirit was going like:'Shinigami-sama!'
And now in this chapter wherein in Shinigami talks about the awakening of Shinigami-powers, Spirit makes a sad face as if he knows something about it.