Status
This term goes back to James Davies' Life and Death and clarifies what one means by alive. Divide groups into three kinds:
- those that are alive without further plays;
- those unsettled groups that may live with one more play, but can be killed by a play of the opponent;
- those groups that are simply dead.
When determining the status of a group, we always assume alternating play. This is as simple as it can be. Complications are introduced by ko.
Some tsumego problems ask one to determine the status of a group. Analogously to the list above, the answer will be one of three kinds:
- The group is dead no matter who plays first. The most interesting sequence will illustrate why the group is dead even if moves to save it are played first.
- If one player plays first, the group can be killed, if the other plays first it can live. This may include sequences with ko and seki. Often in problems only the sequence to either kill or survive is of interest while the opposite is more obvious.
- The group is alive no matter who plays first. The most interesting sequence will show how to resist the best attack.
Velobici: Status problems have a distinct advantage over all other types of life and death problems. One must determine whether or not an additional move is required to settle the inside group. This is exactly the same skill that one is required to exercise repeatedly while playing. Therefore, status problems can be the most rewarding in actual play.