The bandwidth of possibilities which inevitably narrows as possibilities actually occur. In the game of Go or Weiqi, the board is an open set of very wide possibilities, so much so that the game is basically meaningless. Placing the first stone actualizes a range of possibilities. As the interstices on the board become filled with stones and their networks of interactions the game is more and more actualized. At some point, usually when around 3/4s of the board is thus filled, it becomes less and less interesting.