States versus State Descriptions
A state is a set of formulas that describes a single state of the world
- by convention, we include only positive formulas and assume everything else is false
We also need to represent sets of states
- the goal is to be at B and have half a tank of gas, which describes a set of states
- there might be other formulas that describe the world, but we don’t care what state they are
A state description is a set of formulas that describes a set of states
- both positive and negative formulas are allowed in the set
- any formula not mentioned is a “don’t care”