This essay scrutinizes Hart's well-known distinction between external and internal point of view of people toward the social rules. General speaking, the former is the observer's viewpoint, while the latter is the participant's viewpoint. Nevertheless, Hart's distinction is ambiguous and misleading. On the one hand, the internal point of view, according to Hart, refers to the critical reflective attitude of the participants who accept the social rules. However the conception of internal point of view is narrowed to the socialized point of view, it excludes other two kinds of participant's viewpoint: the bad man's (Holmes's version) and the dissenter's, especially in the cases of civil disobedience. On the other hand, Hart distinguished the external from the extreme external point of view. In Hart's opinion, the observers keeping the extreme external point of view do not accept the social rules and are only concerned with them when and because they judge that unpleasant consequences are likely to follow deviation. The extreme external point of view is clearly the participant's viewpoint, namely the bad man's viewpoint. What caused Hart's misunderstanding are his normative judgment about law's function and his ontological assumption about law.