People unavoidably provide reasons for their words and deeds when reasoning in a language-game. Wittgenstein thinks that when people in different language-games argue with one other, they insist on adopting a doubtful attitude toward the reasons provided by the other side. His use of the term “language-game” here is a metaphor, and implies that people in different cultures can scarcely reason with one another. Indeed, according to Wittgenstein’s consideration of concepts of logic in On Certainty, language-games are incompatible with one another because their internal logic and reasons are different from each other. However, in his discussion of empirical propositions Wittgenstein has also shown us the possibility that the internal reasons of one language-game can transmit beyond its own borders and be valid in another language-game.