World-State Orientation and Premature Commitment
In state-space planning, there is close relationship between “states of the world” and “states in the search space”
- in progression planning a search node corresponds to exactly one world state
- in regression planning a search node corresponds to a set of world states
This emphasis on states causes the premature commitment: the planner always needs to know what state(s) it is in, so actions have to be totally ordered, and all variables must be bound