Alvin Plantinga's Modal Argument: The Formalization Problem and the Concept of Existence

Abstract

This paper concerns a modal version of the ontological argument, proposed by the American philosopher Alvin Plantinga in the 70's of the last century. His approach to the formulation of the modal argument has proved to be very productive and still generates interest among ordinary believers, philosophers and theologians alike. The paper focuses on the following issues: (1) the formalisation of the modal argument, (2) the implications of this formalisation, (3) Kant's critique and the modal version of the ontological argument.