This paper explores Otto Muck's metaphysical concept of Weltanschauung (world-view). My objective is to argue that world-views can be rational. To this end, I will first explain the notion of Weltanschauung and illustrate its relation to metaphysical convictions. Next, I will defend the meaningfulness of metaphysical assertions against two objections relating to verification and falsification. The core of the paper focuses on the integrative function of world-views and the criteria according to which one can evaluate their rationality, in particular, Frederick Ferré’s criteria for the rationality of metaphysical systems. The thesis is that the rationality of a world-view can be evaluated in terms of the adequacy of the integrative function it performs. Finally, I will show why, within Muck's framework, dialogue between proponents of different world-views is a postulate of rationality.
