Spectators watch a video screen as Go player Ke Jie plays a match against Google’s artificial intelligence program, AlphaGo, during the Future of Go Summit in Wuzhen in eastern China’s Zhejiang Province, Tuesday, May 23, 2017. Ke Jie, the world’s top-ranked Go player, started a three-round showdown on Tuesday against AlphaGo, which beat a South Korean Go master in a five-round showdown last year. (AP Photo/Peng Peng)