Figure 4 is the same as Fig. 3 except that αB has been moved leftward. Here, in the absence of communication, North wins at αβ regardless of whether he or East moves first or moves are simultaneous. If, however, East can communicate a conditional commitment, he can force North to choose A and an outcome of Aβ. But this commitment is something more than either a promise or a threat; it is both a promise and a threat. He must threaten αB if North chooses α; and he must promise “not AB” if North chooses A. The threat alone will not induce North to avoid α; αB is better than AB for North, and AB is what he gets with A if East is free to choose B. East must commit himself to do, for either α or A, the opposite of what he would do if he were not committed: abstention from AB or immolation at αB.

DEFINE: Schelling clarifies that a single-strategy commitment (threat only or promise only) is insufficient; a mixed commitment combining both is needed to shift the opponent's choice.

Thomas C. Schelling, The Strategy of Conflict, loc. 126