Today Google’s DeepMind team announced that they built a Go-playing AI which beat the European Go champion 5 games to 0. This has been a long time coming! Look at timeline of games conquered by computers:
tic tac toe: 1952
Let’s make a simplistic assumption that the game-playing ability of computers varies as Moore’s Law, which means that it doubles every 18 months. Software has improved as well, so this is a lower bound
So beating checkers required a computer 2^63 times as powerful as beating tic-tac-toe. And chess required a computer 2^4.5 times as powerful as checkers, a factor of 22.6. But the Go program was 379625062 (or 2^28.5) times more powerful than Deep Blue.
These differences are shockingly large, and it turns out that checkers and chess are virtually indistinguishable on the spectrum of human cognition. Both are about 70% of the way between tic tac toe and Go — but who knows how far the spectrum goes?