 Wittgenstein points out that in such a case one could have no criteria for the correctness of one's use of S. Again, several examples are considered.One is that perhaps using S involves mentally consulting a table of sensations, to check that one has associated S correctly; but in this case, how could the mental table be checked for its correctness?It is "[a]s if someone were to buy several copies of the morning paper to assure himself that what it said was true", as Wittgenstein puts it.