To avoid the weaknesses (like logical omniscience and computational complexity of theorem-proving or model checking) of modal approaches, [PPP04,DP03] introduce a theory of intention in the framework of Situation Calculus (See Section 2.4.1). The theory enhances Reiter's action theories [Rei01] with intentional notions of beliefs, desires and intentions. Specifically, cognitive fluents (belief fluents, desire fluents and intention fluents) are introduced and appropriate successor state axioms are specified for these fluents. Belief-producing actions, goal-producing actions and intention-producing actions--such as sense, adopt, abandon, commit or give up--cause cognitive fluents to change in the same manner that ordinary actions cause relational fluents to change. Incorrect beliefs can be represented by having successor belief axioms that do not correspond to successor state axioms.