Game-theoretical semantics (GTS) is an approach to linguistic, logical and philosophical meaning analysis which I began to develop in the early seventies.¹ Its basic idea is closely related to Wittgenstein's notion of language-game, if Wittgenstein's true intentions are appreciated, in that certain rule-governed human activities in it are thought of as constituting the basic language–world relations.² I have taken Wittgenstein more literally than Ludwig did himself and argued that those meaning-constituting language-games are—at least in a number of interesting and important cases—games in the sense of the mathematical theory of games. The concepts of game theory can thus be brought to bear on linguistic and logical semantics.³