 There is, however, in Wittgenstein’s thinking an inclination to think of contradiction in terms of the disintegration of sense, so that even argument by reductio might be understood not in terms of falsehood. (The appearance of this inclination in Tractatus Logico-Philosophicus, for example, is well mapped by Fogelin [1995, Ch. IV].) And it is characteristic of Wittgenstein to talk of philosophical error in terms of nonsense. In §119 of Philosophical Investigations he writes, e.g., ‘The results of philosophy are the discovery of some piece of plain nonsense and of bumps that the understanding has got by running up against the limits of language. They — these bumps — make us see the value of that discovery.’ And in §464: ‘What I want to teach is: to pass from unobvious nonsense to obvious nonsense.’ In the discussion of the possibility of a private language it may well at first seem as though we understand the possibility under consideration. After all we seem to understand the question in §256, ‘Now, what about the language which describes my inner experiences and which only I myself can understand?’ But is Wittgenstein suggesting we only seem to understand this question? 