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The Space of Mental Situations

The following axioms allow us to define precisely the space of mental situations. We use variables for blocks (x, y, z, w, ...), for situations (s, tex2html_wrap_inline574 , ...), for actions (a, tex2html_wrap_inline664 , ...), for mental situations (m, tex2html_wrap_inline668 , ...), for mental actions ( tex2html_wrap_inline670 , tex2html_wrap_inline672 , ...), for formulas in the database (f, tex2html_wrap_inline676 , ...), for subgoals -formulas in the goal stack- (g, tex2html_wrap_inline680 , ...), for sequences of actions, (r, tex2html_wrap_inline684 , ...), and for sequences of mental actions (l, tex2html_wrap_inline688 , ...).

We assume uniqueness of names for every function symbol h, and every pair of distinct function symbols h and g. The symbols h and g are syntactical variables ranging over distinct function symbols; the symbols tex2html_wrap_inline700 to tex2html_wrap_inline702 are syntactical variables ranging over block constants. Axiom gif defines the expression tex2html_wrap_inline704 [12], which means that mental situation tex2html_wrap_inline668 can be reached from mental situation m by executing a nonempty sequence of appropriate mental actions ( tex2html_wrap_inline710 is an abbreviation for tex2html_wrap_inline712 ). We include domain closure axioms for blocks, mental situations, actions, and mental actions. Axiom gif of induction allows us to prove that a property holds for all mental situations that are reachable from a given mental situation.


Josefina Sierra
Tue Jul 21 09:26:01 PDT 1998