Inside the towering Four Seasons hotel in downtown Seoul, the game was approaching the end of its first hour when AlphaGo instructed its human assistant to place a black stone in a largely open area on the right-hand side of the 19-by-19 grid that defines this ancient game. And just about everyone was shocked.
“That’s a very strange move,” said one of the match’s English language commentators, who is himself a very talented Go player. Then the other chuckled and said: “I thought it was a mistake.” But perhaps no one was more surprised than Lee Sedol, who stood up and left the match room.
It’s great that computer AI has done something previously thought impossible, if not extremely far into the future. What’s more interesting to me, is that it is playing moves that surprise (and flummox) humans. It plays moves that the top ranking players would never consider. The fact that new strategies are still being discovered in a game that is both thousands of years old and ‘relatively’ simple, using just two types of pieces and a 19×19 finite grid, is amazing.