In a game that has absolutely no details but its mathematical structure, in which no inadvertent contextual matter can make itself appreciated by a player as something that the other can appreciate too, there may be nothing to work on but a continuum of numbers. And all the numbers can be sorted according to whether they correspond to symmetrical or asymmetrical divisions. If all numbers but one represent an asymmetrical split, then sheer mathematical symmetry is a sufficient rule and a supremely helpful one in concerting on a common choice.

DEFINE: Explains Schelling's concept of using mathematical symmetry as a focal point when games have no contextual clues.

Thomas C. Schelling, The Strategy of Conflict, loc. 658