AlphaGo Defeats Lee Sedol
What Happened
DeepMind's AlphaGo defeated Lee Sedol, one of the greatest Go players ever, 4-1 in a five-game match in Seoul. Go has more possible positions than atoms in the universe — brute force was impossible. AlphaGo used deep reinforcement learning and Monte Carlo tree search. In Game 2, AlphaGo played Move 37 — a move so creative that experts called it 'beautiful' and 'not a human move.'
Why It Mattered
Arguably the most shocking AI moment since Deep Blue. Go was considered decades away from being solved. Move 37 showed AI could be creative, not just efficient. 200 million people watched. Lee Sedol later retired from Go, saying 'AI cannot be defeated.'
Key People
Part of the Deep Learning Breakthrough (2012–2017) era · Browse all competitions & benchmarks · View all 2016 milestones
