A game of surrounding

Go was played in China at least two and a half thousand years ago, and spread to Korea and Japan, where it is called baduk and igo. It is still played by millions of people today, with almost the same rules.

Those rules are few. Players take turns placing a stone on an empty point. A stone stays on the board as long as at least one point next to it is empty — those empty points are its liberties. Stones of the same colour that touch share their liberties and live or die together.

When the last liberty of a stone or group is filled by the other player, it is captured and taken off the board. Everything else in the game — and there is a great deal of it — grows from that one idea.