On the Sick Father, the Repentant Sinner, and Other Problems in Medieval Deontic Logic

Abstract

AbstractMany medieval philosophers and logicians regarded modal logic as a model for epistemic, normative and optative concepts on the basis of their apparent similarities to modal concepts. These interpretations of modal logic led to critical studies of the applicability of modal principles to deontic concepts. Some philosophers presented apparent counterexamples to the deontic interpretation of the Consequence Principle, according to which the consequences of what is obligatory (or permitted) are also obligatory (permitted). These examples are variants of Lennart Åqvist's paradox of the Good Samaritan. In this article it is argued that the examples involve a confusion between the compounded and the divided senses of deontic propositions, and are not genuine counterexamples to the Consequence Principle. If the concept of knowledge is analysed as epistemically satisfactory belief, the paradox of epistemic obligation can be solved in a similar way.