Semantic games are best explained through an analogy to board games with a white and a black player where ties are impossible. We choose a start position c which is any legal position that is reachable from the standard start position of the board game. We have a group of players whom we ask the question: is there a winning strategy for white starting from c?

Let's assume some players say yes and others say no. We choose a player who said "yes" as white and a player who said "no" as black. They play the game. If white (black) loses she has made a mistake and the black (white) player wins a point.

Let's assume all players make the same choice, e.g., they all say "yes". Then we choose a player to be white and we force another player to be black, taking on the role of devil's advocate. If black wins white must have made a mistake and black wins a point. If white wins, we cannot blame black because she was forced.

Here the correspondence to semantic games:

Board Game			Semantic Game

start position 			claim
white				verifier
black				falsifier
winning strategy for white	winning strategy for verifier
game				logical dialog
mistake				mistake, contradiction
game rules			semantic game rules
game depends on start position  game depends on claim

White claims that problem p has a solution of quality q that cannot be improved. Black shows a solution of quality q'>q. White has made a mistake.