Abstract

A new language for epistemic logic is introduced in which the epis- temic operators are of the form j x : x1 : : : xnj with the intended read- ing \x knows of x1 : : : xn that ...". Analogously we can express \t knows of t1 : : : tn that ... ", where t; t1 : : : tn are terms. An advantage of this approach is that we can quantify on the agents, \every y knows of x1 : : : xn that A" or \some expert knows of t1 : : : tn that A" can easily be expressed. The semantics we present for this language is a generalization of the transition semantics, called epistemic transition semantics in which the possible worlds are states of affairs compatible with the epistemic state of some agent. A calculus is presented and shown to be complete with respect to epistemic transition semantics.