- Lee Se-dol, a former Go champion, has announced his retirement, declaring that artificial intelligence has created an opponent that "cannot be defeated."
- Go, a strategic board game that originated in China more than 2,500 years ago, is considered one of the most complex games in the world.
- In 2016, Lee lost a set of matches against AlphaGo, an artificial intelligence developed by DeepMind, a company owned by Google.
- DeepMind's programs have mastered several games and defeated top human competitors, bringing new attention to the rapid growth in AI technology.
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The dominance of artificial intelligence in competitive strategy games has led one of South Korea's top Go players to retire.
Lee Se-dol, 36, told the Yonhap News Agency that he would no longer play professionally, because AI is impossible to overcome.
"With the debut of AI in Go games, I've realized that I'm not at the top even if I become the No. 1 through frantic efforts," Lee said. "Even if I become the No. 1, there is an entity that cannot be defeated."
In 2016, Lee, who was considered the best Go player in the world, lost a set of matches 4-1 against AlphaGo, an AI system developed by the Google-owned company DeepMind.
Dating back more than 2,500 years to China, Go is considered one of the most complex board games in the world, and AlphaGo's mastery brought new attention to the rapid advancement of AI technology.
DeepMind has further improved its program since AlphaGo's match against Lee too. The latest iteration, AlphaGo Zero, was able to beat the original AlphaGo in 100 matches in a row.
DeepMind's AI programs improve by analyzing thousands of professional matches, allowing them to anticipate the opponent's moves and counter with the most effective strategies and counterplays.
Lee will have one last match against an AI opponent before he officially retires in December: He'll be up against HanDol, an AI developed in South Korea that's already defeated the country's top five players. Lee will be given a slight handicap against HanDol, but he still isn't confident about how the match will go.
"Even with a two-stone advantage, I feel like I will lose the first game to HanDol," Lee told Yonhap.
DeepMind's AI programs have mastered some of the most popular strategy games, from classic board games like chess and Go to competitive video games. Last month, DeepMind's "StarCraft II" AI program, AlphaStar, reached the rank of grandmaster, making it better than 99.8% of all human players. AlphaStar has also defeated some of the world's best esports competitors in head-to-head matches across different games.
While AI's superiority over human players seems to be an inevitability, these programs have also helped to push the boundaries of these strategy games, and matches against the world's top players evoke the highest possible level of play.