Practical Reasoning with Norms for Autonomous Software Agents

Autonomous software agents operating in dynamic environments need to
constantly reason about actions in pursuit of their goals, while taking into
consideration norms which might be imposed on those actions. Normative
practical reasoning supports agents making decisions about what is best for
them to (not) do in a given situation. What makes practical reasoning chal-
lenging is the interplay between goals that agents are pursuing and the norms
that the agents are trying to uphold. We offer a formalisation to allow agents
to plan for multiple goals and norms in the presence of durative actions that
can be executed concurrently. We compare plans based on decision-theoretic
notions (i.e. utility) such that the utility gain of goals and utility loss of norm
violations are the basis for this comparison. The set of optimal plans consists
of plans that maximise the overall utility, each of which can be chosen by the
agent to execute. We provide an implementation of our proposal in Answer
Set Programming, thus allowing us to state the original problem in terms of
a logic program that can be queried for solutions with specific properties.