. Function composition operator: .

. The inverse of , *i.e. * the set of states that map
to a given state under (p. ).

. (For a simple projection ).
A generalized inverse. Since only maps certain components of
*S*' to *S*, is *s*' with those components replaced by
their corresponding components in *s* (p. ).

. For a simple reduction from an
environment *E*' to *E*, the function mapping an action *a* from *E*
to the action that implements it in *E*'
(p. ).

. The chain-environment of *n* states (p. ).

*E*. An environment.

. *G* a goal of *E* and *E*' uniformly
reducible to *E*. The existential goal of *G* in *E*': the set of
all *E*'-states that map to a goal state under some binding (p. ).

. The serial product. The Cartesian product of and in which actions from the two environments must be taken separately (p. ).

. The parallel product. The Cartesian product of and in which actions from the two environments must be taken simultaneously (p. ).

. (*E*' an environment uniformly reducible to *E*) The
leftmost-ready binding map from *E*' to *E* (p. ).

*p*. A policy.

. The standard policy for single-material environment
*E* and goal *G* (p. ).

. The singleton environment (the environment with exactly one state). Used to represent a self-resetting tool (p. ).

Wed Apr 2 15:17:20 CST 1997