zero-sum game - a game in which the total of all the gains and losses is zero

scientific theory - a theory that explains scientific observations; "scientific theories must be falsifiable"

economic science, economics, political economy - the branch of social science that deals with the production and distribution and consumption of goods and services and their management

Nash equilibrium - (game theory) a stable state of a system that involves several interacting participants in which no participant can gain by a change of strategy as long as all the other participants remain unchanged