Max Tegmark: 'Machines taking control doesn't have to be a bad thing'

Afew years ago the cosmologist Max Tegmark found himself weeping outside the Science Museum in South Kensington. He'd just visited an exhibition that represented the growth in human knowledge, everything from Charles Babbage's difference engine to a replica of Apollo 11. What moved him to tears wasn't the spectacle of these iconic technologies but an epiphany they prompted. "It hit me like a brick," he recalls, "that every time we understood how something in nature worked, some aspect of ourselves, we made it obsolete. Once we understood how muscles worked we built much better muscles in the form of machines, and maybe when we understand how our brains work we'll build much better brains and become utterly obsolete." Tegmark's melancholy insight was not some idle hypothesis, but instead an intellectual challenge to himself at the dawn of the age of artificial intelligence. What will become of humanity, he was moved to ask, if we manage to create an intelligence that outstrips our own?