21 Lessons for the 21st Century

by Yuval Noah Harari

On December 7, 2017, a critical milestone was reached, not when a computer defeated a human at chess—that’s old news—but when Google’s AlphaZero program defeated the Stockfish 8 program. Stockfish 8 was the world’s computer chess champion for 2016. It had access to centuries of accumulated human experience in chess, as well as decades of computer experience. It was able to calculate seventy million chess positions per second. In contrast, AlphaZero performed only eighty thousand such calculations per second, and its human creators had not taught it any chess strategies—not even standard openings. Rather, AlphaZero used the latest machine-learning principles to self-learn chess by playing against itself. Nevertheless, out of a hundred games the novice AlphaZero played against Stockfish, AlphaZero won twenty-eight and tied seventy-two. It didn’t lose even once. Since AlphaZero had learned nothing from any human, many of its winning moves and strategies seemed unconventional to the human eye.