Emotion is an important issue in Wittgenstein’s philosophy of psychology, yet the literature on this topic is quite small. Wittgenstein’s philosophical investigation is a grammatical one, and he tries to dissolve philosophical problems by using many philosophical methods. In this paper I examine the grammatical rules for some emotion words and the methods he employs in dealing with the philosophical problem of emotion. To facilitate this examination, I first analyze Wittgenstein’s treatment of the problem of sudden understanding, where the grammar (...) and methods are easier to comprehend. I will then show that the grammar and methods used by Wittgenstein in the cases of sudden understanding and emotion are rather similar. (shrink)