Italian cameo bracelet representing the days of the week, corresponding to the planets as Roman gods: Diana as the Moon for Monday, Mars for Tuesday, Mercury for Wednesday, Jupiter for Thursday, Venus for Friday, Saturn for Saturday, and Apollo as the Sun for Sunday. Middle 19th century, Walters Art Museum.
Glossary of game theory terms. Constant Sum. In a constant sum game, the sum of all players' payoffs is the same for any outcome. Hence, a gain for one participant is always at the expense of another, such as in most sporting events. Given the conflicting interests, the equilibrium of such games is often in mixed strategies.
The theory of zero-sum games is vastly different from that of non-zero-sum games because an optimal solution can always be found. However, this hardly represents the conflicts faced in the everyday world. Problems in the real world do not usually have straightforward results. The branch of Game Theory that better represents the dynamics of the world we live in is called the theory of non-zero-sum games. Non-zero-sum games differ from zero-sum games in that there is no universally accepted solution.