Google's AlphaGo has stomped to victory for a fourth time against Go world champion Lee Sedol. That makes it a resounding victory for the AI, which has won four of the five games it's played against its human opponent. Google's AI won the first three matches in the best-of-five tournament, but it's traditional in Go to play the remaining games. Sedol did manage to win the fourth and it was thought he might be able to exploit the weakness he found in software again. Google Deepmind's Demis Hassabis put the odds at about 50-50.
But it seems that Google's AI is simply too smart for the reigning world champion to fully defeat. AlphaGo won the final game by resignation after 280 moves, in a match that Google has described as "tight until the very end". After this final game, Sedol gave the following statement during a press conference:
I am very sorry that the Google DeepMind Challenge Match is over. Today I wanted to bring the match to a successful conclusion. Personally, I am regretful about the result, but would like to express my gratitude to everyone who supported and encouraged me throughout the match... I have questioned at some points in my life whether I truly enjoy the game of Go, but I admit that I enjoyed all five games against AlphaGo. After my experience with AlphaGo, I have come to question the classical beliefs a little bit, so I have more study to do.
It's not the first time he's sounded so downbeat. After the third game, Sedol apologised for not beating the AI:
I don't know how to start or what to say today, but I think I would have to express my apologies first. I should have shown a better result, a better outcome, and better content in terms of the game played, and I do apologise for not being able to satisfy a lot of people's expectations. I kind of felt powerless. If I look back on the three matches, the first one, even if I were to go back and redo the first match, I think that I would not have been able to win, because I at that time misjudged the capabilities of AlphaGo.
The AI already beat the three-time European Go champion Fan Hui over the course of five matches. But Sedol was largely considered to be a much harder challenge, having dominated the world of Go for much of his professional career.
The AI has now won nine of ten games that it's played against the reigning World and European Go champions, which is probably enough for it to be taken very seriously. Indeed, it's a stark reminder that AI technology is now advancing at a startling rate.
Image by AP