In Turing’s 1950 paper, "Computing Machinery and Intelligence," he argued that when we build intelligent machines, we will not be creating souls but building the mansions for the souls that God creates. When I first visited Google, right about the time it went public, I walked around and saw what they were doing and realized they were building a very large distributed AI, much as Turing had predicted. And I thought, my God, this is not Turing’s mansion—this is Turing’s cathedral. Cathedrals were built over hundreds of years by thousands of nameless people, each one carving a little corner somewhere or adding one little stone. That’s how I feel about the whole computational universe. Everybody is putting these small stones in place, incrementally creating this cathedral that no one could even imagine doing on their own.