TwoSquares/Discussion

RobertJasiek: After a century of questionable attempts of trying to define life by shape and reinventing the wheel, this is another questionable attempt. Instead, life depends on move sequences and its definition has been solved:

• Japanese 2003 Rules
• Model of WAGC Rules
• Simplified Japanese Rules
• FormalDefinitionsOfEye#toc1
• FormalDefinitionsOfEye#toc2
• Greedy Ancient Rules in Mathematical Go Endgames

Note that shape approaches can be useful for purposes other than defining life. For example, a shape approach can be useful for pattern matching in computer programs, which need not always be correct about what is, or is not, alive.

KjeldPetersen: I believe life (or dead) of a group strongly depends on a graph of connected stones, that must have certain properties for the group to be alive. You can build the graph in sequence of moves, that will add/remove nodes and vertices in the graph, but in the end the life (or dead) of the group depends on the properties of the graph. GeneralGraphGo