Non-Monotonic Temporal Logics That Facilitate Elaboration Tolerant Revision of Goals

Abstract

Temporal logics are widely used in specifying goals of agents. We noticed that when directing agents, humans of-ten revise their requirements for the agent, especially as they gather more knowledge about the domain. However, all ex-isting temporal logics, except one, do not focus on the revi-sion of goals in an elaboration tolerant manner. Thus formal temporal logics that can allow elaboration tolerant revision of goals are needed. As non-monotonic languages are often used for elaboration tolerant specification, we propose to ex-plore non-monotonic temporal logics for goal specification. Recently, a non-monotonic temporal logic, N-LTL, was pro-posed with similar aims. In N-LTL, goal specifications could be changed via strong and weak exceptions. However, in N-LTL, one had to a-priori declare whether exceptions will be weak or strong exceptions. We propose a new non-monotonic temporal logic, that not only overcomes this, but is also able to express exception to exceptions, strengthen and weaken preconditions, and revise and replace consequents; all in an elaboration tolerant manner.