In early December, researchers at DeepMind, the artificial intelligence company owned by Google's parent corporation, Alphabet, filed a dispatch from the frontiers of chess.

A year earlier, on December 5, 2017, the team had stunned the chess world with its announcement of AlphaZero, a machine-learning algorithm that had mastered not only chess but also shogi, or Japanese chess, and Go. The algorithm started with no knowledge of the games beyond their basic rules. It then played against itself millions of times and learned from its mistakes. In a matter of hours, the algorithm became the best player, human or computer, the world has ever seen.