An SMT-Based Approach to the Verification of Knowledge-Based Programs

We give a general-purpose programming language in which programs can reason about their own knowledge. To specify what these intelligent programs know, we define a “program epistemic” logic, akin to a dynamic epistemic logic for programs. Our logic properties are complex, including programs introspecting into future state of affairs, i.e., reasoning now about facts that hold only after they and other threads will execute. To model aspects anchored in privacy, our logic is interpreted over partial observability of variables, thus capturing that each thread can “see” only a part of the global space of variables. We verify program-epistemic properties on such AI-centred programs. To this end, we give a sound translation of the validity of our program-epistemic logic into first-order validity, using a new weakest-precondition semantics and a book-keeping of variable assignment. We implement our translation and fully automate our verification method for well-established examples using SMT solvers.