Identifying Resources
 
 
- Use definition on goal specification
- 
- Types not specified in goals are resources
 
- Explicitly specify resources
     (effects (arm-empty <rob>))
       (params  (<rob> ROBOT) (<ob> OBJECT) (<underob> OBJECT))
           (p1  1      (s1  (PUT-DOWN  <rob> <ob>)))
           (p2  4      (s1  (STACK  <rob> <ob> <underob>))))))
     (effects (holding <rob> <ob>))
       (params  (<rob> ROBOT) (<ob> OBJECT) (<underob> OBJECT))
           (p1  1 (s1  (PICK-UP  <rob> <ob>)))
           (p2  4 (s1  (UNSTACK  <rob> <ob> <underob>)))))))