- [[positive-sum game]] # Idea If one person wins (+1), the other person loses (-1), so the sum (+1 + -1) is 0. Thus, a "zero sum game." Because of this zero-sum property, zero sum games lead to competition. For example, a chess match is zero sum game. One party's win necessitates another party's loss. Competing for market share too—as one firm gains market share, other firms lose the equivalent amount of that market share. # References