 Critics of Wittgenstein have found the argument, so interpreted, quite unconvincing. Surely, they say, the untrustworthiness of memory presents no more and no less a problem for the user of a private language than for the user of a public one. No, Wittgenstein’s defenders have said, for memory-mistakes about public objects may be corrected, memory-mistakes about private sensations cannot; and where correction is impossible, talk of correctness is out of place. At this point critics of Wittgenstein have either denied that truth demands corrigibility, or have sought to show that checking is possible in the private case too. (Kenny[ 1973] pp. 191–2)