"As far as the horror genre, I think The Exorcist is the scariest movie of all time. It’s like head and shoulders above… there’s nothing more terrifying, or deeply sinister than that. When I saw The Exorcist, at that time when I was a kid, I may have slept with the light on. I can’t remember the exact time [I saw it], but I remember being literally knocked back. You have the pure theological question about, you know, “What is the role of evil and what is the nature of evil and what is its function?” And I think in The Exorcist the point is, the reason it’s here is to try and make us give up hope, and find the courage to not give up hope. Evil wants to so demoralize you that you abandon all hope; it’s only human beings’ capacity to love and to fight back. But that’s the role of evil: To challenge, and to make you choose. And growing up as a Catholic, too, I was immersed in the theology and doctrine of the church, so that movie was a serious, serious f-cking movie."
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