"Wicked" by Gregory Maguire: Author's reason for Wickedness is a religious explanation for multiple personality

“When goodness removes itself, the space it occupied corrodes and becomes evil, and maybe splits apart and multiplies…”

“ 'Well I wouldn’t know an evil thing if it fell on me,' said Galinda..."

" 'But they believe in evil still,' said Galinda with a yawn. 'Isn’t that funny, that the deity is passé but the attributes and implications of deity linger---' "

“ 'I am about to sleep, because this is profoundly boring to me,' Galinda said, but Elphaba was grinning from ear to ear" (1, p. 97).

1. Gregory Maguire. Wicked: The Life and Times of the Wicked Witch of the West. London. Headline Review. 1995/2024. 

2. Michiko Kakutani's 1995 [Negative] New York Times Book Review of Wicked.

https://www.nytimes.com/1995/10/24/books/books-of-the-times-let-s-get-this-straight-glinda-was-the-bad-one.html