Why programmers should play go

Go is an ancient strategy game with simple rules and a profound degree of complexity.
Software development is the art of managing complexity using a limited number of rules, structures, and patterns.
Programmers should play Go.

Go in 2^8 words or less.

The beauty of Go is its combination of simplicity and complexity. On the one hand, go has only a handful of rules. Place stones, don’t get completely surrounded, control territory. Like chess, the mechanics can be picked up in a few minutes, though Go only has a single type of “move”, and only one edge case (the ko rule). And like chess, one can spend a lifetime discovering the strategic and tactical layers of the game.

While chess is quite complex and rich, such that it took a 30-node supercomputer to defeat the reining chess champion, no computer comes close to defeating even a skilled amateur Go player. There are 361 positions on a Go board, and with two players, there are 2.08168199382×10^170

valid positions. That’s quite a bit bigger than a googol (yes, that is the correct spelling). Realistically, there are something on the order of 10400 possible ways that a typical game could play out. And the number of possible moves roughly follows 361!, which means that only 20 moves in, there are many googols of possible ways that the game could shake down. (As a fun exercise, try plugging 361! into an online factorial calculator.)

Managing complexity

So how does one play Go, given this near-infinite complexity? On a tactical level, a player approaches Go like chess, thinking several moves ahead. But this only works in small spaces, like a tight battle in a small sector of the board. Beyond there, there are just too many possibilities. So on a strategic level, a player must think in shapes or patterns. These shapes provide shorthand ways of managing the complexity of Go. As a non-master, I may have no idea how things will proceed in one sector of the board, but I may be able to recognize strong and weak patterns of stones, vulnerable shapes and effective formations.

But there’s more: Go has several sorts of patterns. Beyond shapes, there are Go proverbs. These can be general: “Your opponent’s good move is your good move”; specific: “Don’t try to cut the one-point jump”; funny: “Even a moron connects against a peep”; and meta: “Don’t follow proverbs blindly.” These proverbs are principles which help a player make good decisions. They are less specific than shapes, and so they provide guidelines for whatever situations may arise on the Go board. Proverbs often conflict, and a player must determine when and how to apply them.

Finally, there are joseki. Joseki are patterns of play that are considered even for both sides. They typically happen in the corners of the board, and typically at the beginning of the game. Interestingly, there is a Go proverb that says “Learning joeski costs two stones,” meaning that memorizing these patterns isn’t helpful. Instead, a player should learn from joseki by understanding what is going on in each move.
Patterns in Go, patterns in software design

Each of these Go patterns has a rough programming analogue.

Shapes in Go aren’t unlike software design patterns. While there is nothing preventing you from placing logic in your views, this shape is recognized to be a weak one. Think of Gang-of-Four design patterns: the MVC, Adapter, and Factory patterns are recognized to be helpful in some circumstances (and not appropriate in others).



Why programmers should play go