If two players jointly expect a priori the same outcome, and confidently recognize it as their common expectation, they must have the intellectual power to pick a particular point in common. If the whole $100 can be divided to the nearest penny, there are 9,999 relevant divisions to consider, one of which would have to be picked simultaneously but separately by both players as their expectations of the outcome. But how can two people concert their selections of one item out of 9,999, in the sense that their expectations focus or converge on it, except with odds of 9,999 to 1 against them? The answer must be that they utilize some trick, or clue, or coordinating device that presents itself to them. They must, consciously or unconsciously, use a selection procedure that leads to unique results. There must be something about the point they pick that distinguishes it—if not in their conscious reasoning, at least in our conscious analysis—from the continuum of all possible alternatives.

DEFINE: Introduces the concept of a coordinating device or 'focal point' that lets players select among many alternatives without communication.

Thomas C. Schelling, The Strategy of Conflict, loc. 655