A zero-sum game describes any situation, contest or negotiation in which one party’s gain comes directly and exactly at another party’s expense. Add up everyone’s winnings and losses and the total is zero: nothing new is created and nothing is destroyed, it simply moves from one side to the other. The phrase is used well beyond actual games, in economics, politics and everyday arguments about resources, to describe circumstances where helping one person or group necessarily means someone else loses out by the same amount.
The term is often misunderstood. Many people take “zero-sum” to mean that nobody wins, or that the outcome is somehow neutral for everyone, but the opposite is true: there are winners and losers, and their fortunes are precisely linked, one going up exactly as far as the other goes down. Negotiations over pay, territory or market share are often described this way when the two sides are seen as fighting over a fixed pie rather than one that might grow.
What’s the origin of the phrase ‘a zero-sum game’?
The term comes from game theory, the branch of mathematics concerned with strategic decision-making. It was coined by the mathematician John von Neumann and the economist Oskar Morgenstern in their 1944 book Theory of Games and Economic Behavior, where they classified games according to whether the total payments among the players summed to zero. As they put it, “We shall call games of the first mentioned type zero-sum games.” A zero-sum game in their technical sense was simply one in which one player’s payoff was always the mirror image of another’s loss, as opposed to games where the total outcome could vary depending on how the players behaved, allowing for mutual gain or mutual loss.
From this precise mathematical definition, the phrase spread into general use across economics, politics and business commentary, applied loosely to any competitive situation seen as a fixed contest between winners and losers rather than one with room for shared benefit.
Its popularity has also produced a common corruption, “zero-sum gain,” which turns up frequently in speech and writing. This version is considered wrong, since the whole point of the original term is the exact balance between gain and loss, not gain on its own. The mistake likely comes from mishearing “game” as “gain,” an easy slip given how the phrase is usually spoken aloud rather than read.