The July 23, 2009 New York Daily News and other news sources reported that Pitt told the German magazine Bild that "I'm probably 20 percent atheist and 80 percent agnostic."
The relevant portion of the Bild.com interview:
BILD: Do you believe in God?
Brad Pitt (smiling): “No, no, no!”
BILD: Is your soul spiritual?
Brad Pitt: “No, no, no! I’m probably 20 percent atheist and 80 percent agnostic. I don’t think anyone really knows. You’ll either find out or not when you get there, until then there’s no point thinking about it.
By the time he entered college, Pitt had scuttled his fundamentalist beliefs. "When I got untethered from the comfort of religion, it wasn't a loss of faith for me, it was a discovery of self," he says. "I had faith that I'm capable enough to handle any situation. There's peace in understanding that I have only one life, here and now, and I'm responsible." 
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