ABSTRACT. The private language argument in Wittgenstein has important implications for how self consciousness should be characterised. Some recent cognitivist theories claim that the self is really the sense of being a mental presence whilst the body is merely a container for these vital mental attributes. The cognitivist perspective emphasizes that mental states are internal to the mind thereby promoting the notion that the self is separate from the body. The private language argument is used to critique cognitivism through an examination of the notion of privacy which this conception of mental states depends upon. The assumption that the mental is essentially private leads to the supposition that it is intelligible to attribute self consciousness to either minds or bodies. On Wittgenstein's view new theories of the self are not required but a grammatical investigation into the employment of 'self consciousness' and its cognates (including their psychological and neuroscientific uses) is.