Simulative Inference About Nonmonotonic Reasoners

If one has attributed certain initial beliefs to an agent, it is sometimes possible to reason about further beliefs the agent must hold by observing what conclusions one’s own reasoning mechanism draws when given the initial beliefs as premises. This technique is called simulative inference. In an earlier paper, we described a logic of belief in which the reasoning that generates beliefs is modeled explicitly as a computational process. We used this logic to characterize a class of computational inference mechanisms for which simulative inference is sound, under the assumption that the observer and the observed have similar mechanisms. In this paper, we present a different form of simulative inference, and show that unlike the earlier form, it is sound even for some mechanisms that perform defeasible inference.