Adapting Methods to Novel Tasks in Proof Planning

In this paper we generalize the notion of method for proof planning. While we adopt the general structure of methods introduced by Alan Bundy, we make an essential advancement in that we strictly separate the declarative knowledge from the procedural knowledge. This change of paradigm not only leads to representations easier to understand , it also enables modeling the important activity of formulating meta-methods, that is, operators that adapt the declarative part of existing methods to suit novel situations. Thus this change of representation leads to a considerably strengthened planning mechanism. After presenting our declarative approach towards methods we describe the basic proof planning process with these. Then we deene the notion of meta-method, provide an overview of practical examples and illustrate how meta-methods can be integrated into the planning process.