It really depends on how good AlphaGo is at avoiding mistakes. If you get critical points on the board, it's possible to create a resilient structure that is d

It really depends on how good AlphaGo is at avoiding mistakes. If you get critical points on the board, it's possible to create a resilient structure that is defensible against comebacks. But when I play, there are times when I can make an overwhelming comeback because my opponent missed one critical move. I've likewise had it done to me. This is of course probably less common at higher and higher levels of play. I'm reminded of the time when Deep Blue made a buggy move that totally threw Kasparov off because it was so counterintuitive. But it turned out to be a real mistake. If Kasparov had kept his composure, who knows what could have happened? http://www.wired.com/2012/09/deep-blue-computer-bug/ http://www.wired.com/2012/09/deep-blue-computer-bug/ Of course, as been stated here, AlphaGo doesn't have the issue of having to keep composure, while Lee does have that issue and pressure. But who's to say that AlphaGo won't make a similar significant mistake, and that Lee won't be able to capitalize on it to make a comeback in that particular game? edit: admittedly, as pshc as noted, the search space probably grows smaller as the game continues. edit 2: suddenly, his comment disappeared for some reason?