Abstract: | Abstract. The starting point of deontic logic is the distinction between non-normative necessity and normative necessity. The first part of the paper shows that the distinction between normative necessity and non-normative necessity occurs already in Aristotle's Orgunon . The second part of the paper makes a further distinction within normative deon itself: The distinction between deontic deon and anankastic deon . Anankastic deon behaves differently from deontic deon in a very important respect: Deontic indifference has no anankastic counterpart. |