It should particularly be noted that to assert the influence of "labels" (that is, of the symbolic and connotative details of the game) and the dependence of the theory on empirical evidence does not involve the question of whether game theory is predictive or normative—concerned with generalizations about actual choice or the strategy of correct choice. The assertion here is not that people simply are affected by symbolic details but that they should be for the purpose of correct play. A normative theory must produce strategies that are at least as good as what people can do without them. More, it must not deny or expunge details of the game that can demonstrably benefit two or more players and that the players, consequently, should not expunge or ignore in their mutual interest.

DEFINE: Tightly distinguishes normative (strategy of correct play) from predictive (generalizations about actual choice) game theory, and argues a normative theory must incorporate symbolic details.

Thomas C. Schelling, The Strategy of Conflict, loc. 231