 The issue’s significance can be seen by considering how the argument is embedded in the structure of Philosophical Investigations. Immediately prior to the introduction of the argument (§§241f), Wittgenstein suggests that the existence of the rules governing the use of language and making communication possible depends on agreement in human behaviour—such as the uniformity in normal human reaction which makes it possible to train most children to look at something by pointing at it. (Unlike cats, which react in a seemingly random variety of ways to pointing.) One function of the private language argument is to show that not only actual languages but the very possibility of language and concept formation depends on the possibility of such agreement.