Google’s AlphaGo AI defeats world Go number one Ke Jie

Google’s AI AlphaGo has done it again: it’s defeated Ke Jie, the world’s number one Go player, in the first game of a three-part match. AlphaGo shot to prominence a little over a year ago after beating Korean legend Lee Se-dol 4-1 in one of the most potent demonstrations of the power of artificial intelligence to date. And its defeat of Ke shows that it was only getting started.

“I think everyone recognises that Ke Jie is the strongest human player,” 9th-dan professional and commentator Michael Redmond said before the match. And despite defeat, Ke’s strategy suggested that the 19-year-old Chinese prodigy has actually learned from AlphaGo’s often unorthodox approach. “This is Master’s move,” said Redmond of one of Ke’s earliest plays, referring to the pseudonym that AlphaGo used for a recent series of online matches in which it racked up a 60-game winning streak.

AlphaGo won by just half a point, the closest margin possible, but that’s characteristic of its playing style. The AI doesn’t appear to care about the margin of victory, instead choosing moves that it has determined are the most likely to lead to a win. The result was technically close, but AlphaGo looked like winning from a relatively early stage in the game.

“I think it was a really wonderful game,” DeepMind CEO and co-founder Demis Hassabis said at the post-game press conference. “Huge respect to Ke Jie for playing such a great game and pushing AlphaGo to its limits.”

Ke and AlphaGo are facing off as part of the Future of Go Summit being held by Google in Wuzhen, China this week. The second game will be on Thursday (China time; Wednesday evening in the US) while the finale will be on Saturday. Friday will see AlphaGo further put to the test in two stipulation matches; one where it acts as a teammate to two Chinese pros playing each other, and another where it takes on five Chinese pros all at once.