" There it lies, I think, Damien … possession; not in wars, as some tend to believe; not so much; and very rarely in extraordinary interventions such as here … this girl … this poor child. No, I tend to see possession most often in the little things, Damien: in the senseless, petty spites and misunderstandings; the cruel and cutting word that leaps unbidden to the tongue between friends. Between lovers. Between husbands and wives. Enough of these and we have no need of Satan to manage our wars; these we manage for ourselves … for ourselves. "

― William Peter Blatty , The Exorcist