 Another account of introspection, identified most closely with Shoemaker (1996a,b,c,d), is that the immediacy of introspective belief follows from the fact that occurrent mental states and our introspective beliefs about them are functionally interdefined. For example, one satisfies the definition of being in pain only if one is in a state that tends to cause (in creatures with the requisite concepts who are considering the question) the belief that one is in pain, and one believes that one is in pain only if one is in a state that plays the belief role, and is caused directly by the pain itself. On this account of introspection, the immediacy and non-inferential nature of introspective belief is not merely compatible with functionalism, but required by it.