It turns out that Google's AlphaGo isn't unstoppable. The AI had won three out of the five matches in its series against Lee Sedol, but the computer's human opponent has now triumphed. Lee Sedol was upset after his loss to the system yesterday, apologising for his failure to beat the machine. He was far more upbeat after his win, noting that "I've never been congratulated so much just because I won one game!"
According to AlphaGo's team, the machine made an error early in the game, but didn't realise that it had done so until ten moves later:
Mistake was on move 79, but #AlphaGo only came to that realisation on around move 87
— Demis Hassabis (@demishassabis) March 13, 2016
The machine resigned after five hours, leaving Sedol the victor. As the pair have played one another, it seems that they have been learning and understanding each other better with each match, according to South Korean commentator Song Taegon:
It seems Lee Sedol can now read AlphaGo better and has a better understanding of how AlphaGo moves. For the 5th match, it will be a far closer battle than before since we know each better.
With that in mind, it will be interesting to see how the fifth and final game ends up. That match will be played on Tuesday, March 15. Has Sedol learned enough about the machine and how it plays to triumph once again?
Despite the win, the machine has won eight out of the nine games that it's played: while its winning streak is now broken, it's an amazing triumph for artificial intelligence: Go is an incredibly difficult game to play, with an enormous number of possible moves to compute.
Still, the loss for the machine shows that there's still some glimmer of hope for humanity.
Top image credit: AP Images