Abstract  This paper reveals an implicit ontological assumption that is presupposed in common thought. This assumption results in the fact that people usually do not make any distinction between 'the object a' and 'the object a at a given moment'. This laziness causes many inconsistencies. Several attempts to solve these inconsistencies are studied, and the most natural one is elaborated, namely the one obtained by applying Classical Logic to an ontological correct domain. This solution has a drawback with respect to communication, which is solved by the changeadaptive logic CAL2. This nonmonotonic, paraconsistent logic, belongs to the family of ambiguityadaptive logics. It has the special characteristic that it solves inconsistencies by the introduction of more precise names for objects, more exactly names that refer to objects at a moment. The dynamics of the logic captures the change in objects. CAL2 has a nice proof theory, and an intuitive semantics. Interesting results and applications are commented upon, for instance those making use of the notion 'periods of invariance'. Of course, the philosophical background is discussed.
