Inference and Update
Fernando R. Velázquez-Quesada

Abstract:
We look at two fundamental logical processes, often intertwined in
planning and problem solving: inference and update. Inference is an
internal process with which we uncover what is implicit in the
information we already have. Update, on the other hand, is produced by
external communication, usually in the form of announcements and in
general in the form of observations, giving us information that might
have been not available (even implicitly) before. Both processes have
received attention from the logic community, usually separately. In
this work, we develop a logical language that allows us to describe
them together. We present syntax and semantics, as well as a complete
axiom system. We also discuss similarities and differences with other
approaches, and we mention some possible ways the work can be
extended.