Two Traditions in the Logic of Belief: Bringing them Together

The terms ‘epistemic logic’ and ‘doxastic logic’ were introduced by Georg Henrik von Wright in his 1951 An essay in modal logic [8], but it was not until Jaakko Hintikka published his seminal book Knowledge and Belief [4] that the discipline named by them took off. During the following ten to fifteen years epistemic/doxastic logic received a good deal of attention in the philosophical community, but towards the end of the 1970s the philosophers seem to have considered that the theme had been played out.1 As often happens, however, interest in the subject was rekindled in a different quarter: computer scientists discovered or re-invented epistemic logic, as they prefer to call the subject; at the present time it is flourishing.2