Causality As a Key to the Frame Problem

Even we human cannot solve the frame problem, that is, we cannot completely describe conditions for a certain action to succeed, nor can we completely predict what will happen as the result of an action. Nevertheless, in daily life we can act as if there were no such problem, because we use some heuristics to bypass it. In this paper, we propose that the concept of causality is the heuristics. We also claim that temporal ordering in causal relation is not essential. Any partial ordering su ces but once the order is xed, it should be followed even in reverse order reasoning such as inferring past from future. We formalize causal reasoning and apply it to YSP. We observe that there are two kinds of non-monotonicity in the reasoning of changes: one due to lack of information, the other due to change itself. Traditionally, situation calculus with non-monotonic logics of various kind are used to attack the frame problem. Two kinds of monotonicity are mixed in those formalisms. It is mainly due to the framework of situation calculus, which is essentially a schema to map dynamic changes into static logical framework. Nonmonotonicity due to change was then mapped into non-monotonicity due to lack of information. In our formalism, we separate them. Non-monotonic reasoning is used for change of information, causality is used to change of states. For the non-monotonic reasoning part, we have few to add.