Five years ago, an artificial intelligence system developed by DeepMind defeated world-class Go player Lee Sedol at his own game. Go, an ancient board game both simpler and exponentially more complex than chess, was thought to be the last bastion of human dominance in a world where computers were getting smarter with each passing day. A decade prior, even moderately strong amateurs could defeat the best Go-playing programs, so for one to unseat not just a pro, but the highest ranked person in the world, was an accomplishment nobody thought would happen for at least another ten years.
The series of games was captured in an award-winning documentary titled AlphaGo, which is available for free on YouTube. What could have been the story of a program steamrolling the best player in the world instead becomes a character study of the man who dared to compete with it. Lee Sedol manages to be both confident and humble, his certainty he’ll sweep the series 5-0 giving way to his enormous respect for his opponent and its programmers. When he loses the first game, he apologizes for letting down his country. When the loses the second and third, his face falls. His posture slackens. Every defeat chips away at him more.
A remarkable thing happens in the fourth match. In the 78th move, Lee plays a wedge that baffles the machine, one that it wouldn’t have expected from even 1 in 10,000 players. And it never recovers from that shock, going on to resign the game.
The series would end 1-4 in AlphaGo’s favor. In 2019, Lee Sedol would announce his retirement from Go, saying that AI ensured he could never be the top player in the world. But this doesn’t take away from the fact that for one day he was unmatched, stronger than any player either born or built.