 Immunity to this sort of error should not be conflated with another sort of epistemic security that is often discussed under the heading of self-knowledge (see entry on  self-knowledge).  Some philosophers have held that, for a range of mental states, one cannot be mistaken about whether one is in them. Thus, for example, if one sincerely judges that one has a pain, or that one believes that P, then it cannot turn out that one is not in pain, or that one does not so believe. That the kind of immunity to error described by Wittgenstein differs from this sort of epistemic security follows from the fact that one may be sceptical of the latter while accepting the former. That is, one may reject the claim that sincere judgements that one has a pain cannot be mistaken (perhaps it is possible to mistake a sensation of coldness for one of pain), whilst nevertheless maintaining that if one is introspectively aware of a pain, then that pain must be one’s own. Immunity to errors of this sort has been taken, by a number of philosophers, to be importantly connected to self-consciousness.