[@Fubsy]

Well to destroy the book is nothing. The book is merely the record.
The knowledge itself transcends the book. As such X would challenge Muorival to find the book first.
Because the book isn't the important thing, the knowledge is.
And you'd need a tool to erase knowledge itself...

Of which X's planned artifact just does that. It grants knowledge and removes knowledge. It holds the universal knowledge of every sentient being that was, is and will be except X to which releasing the secrets would allow everything in existence to know something. But to strike something out from the very same book would be to make everyone seem to magically 'forget' something.