AlphaGo

Go fans have noticed a couple of key moments in the match between world champion Lee Sedol and Google's DeepMind AlphaGo computer. They appear to show Lee realising for the first time just how outmatched he was by the machine.

After his 3-0 defeat today, Lee told the press:

I apologise for being unable to satisfy a lot of people's expectations. I kind of felt powerless," Lee said, acknowledging that he had "misjudged" the computer programme's abilities.

"Yes, I do have extensive experience in playing the game of Go, but there was never a case where I was under this much pressure.... and I was incapable of overcoming it."

Lee's first realisation that AlphaGo was playing at a level w-a-a-a-y above him appears to have come at move W107 in Game 1, as noticed by this thread on Reddit. We've made a gif of the move below. AlphaGo, playing in white, drops a stone on the right side of the board about halfway up, at the lower diagonal from three black stones arranged vertically. It's completely unexpected, because it seems to be unconnected with the rest of the white strategy on the board. Redditor "balancetraveller" wrote:

Lee literally dropped his jaw at W102. Lee's reaction was not aired in the official YouTube live stream. The move is considered the tide-turning move.

You can see a video of the move here, at timestamp 2.30.20. This gif shows that at first he seems paralysed, and then he rocks backwards in surprise:

It was Game 2 when AlphaGo's superiority was confirmed, as noted by Wired. Move 37 by AlphaGo baffled everyone who saw it:

[European champion] Fan Hui thought the move was rather odd. But then he saw its beauty. "It's not a human move. I've never seen a human play this move," he says. "So beautiful." 

You can watch the move on video here at timestamp 1.18.27. AlphaGo, playing black, puts a stone on the right-middle of the board, at a diagonal to an isolated white stone. This photo shows Lee's reaction: He gets up from his chair and walks away from the board. You can see Lee's empty chair at right.

Who:Lee Sedol

What:between world champion Lee Sedol and Google's DeepMind AlphaGo computer

How:Lee realising for the first time just how outmatched he was by the machine.

Keyword:
expectations 預期
acknowledging 確認
incapable 不能勝任的
vertically 垂直的