This chapter shows that if we accept the view that knowledge of the facts may never be possible, then we cannot immunize knowledge of the content of ‘appearances’ against radical sceptical doubt either, which leaves it impossible to explain, without appealing to incoherent notions such as the Myth of the Given and private ostensive definition, how our putative ‘external world’ propositions can have the conceptual content that they do at all. Given that we are able to formulate such propositions, however, it must be false that we can never have knowledge of how things are (only of how they appear).