Thank you very much! I wasn't aware that part of the story was no longer cannon! I'm starting to re-read berserk and there's a lot that I need to remember. Either way, I appreciate your clarification~You're mistaken about the meaning of "Idea" in the name "Idea of Evil". I don't blame you because it's easily confusing, but it's actually a Greek word (not an English one!) Miura uses in reference to Plato's theory of the same name. The meaning of the word is meant to be "source/origin", as in "Source of Evil". Our understanding of how that being was created is mostly informed by a part of the story that isn't cannon anymore, so it's hard to be fully autoritative about it, but in short, no it wouldn't be enough for people to think good thoughts or be happy for it to change.
If you're interested, you can find the dialog between the Idea of Evil and Griffith (from episode 83, that was removed from the story) here.
Furthermore, our undestanding is that Griffith is currently executing a plan that was conceived by the Idea of Evil, so it would make no sense for that plan to be detrimental to it.
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