Formulating problems.
In the preceding section we proposed a formulation of the problem of getting to Bucharest in
terms of the initial state, actions, transition model, goal test, and path cost. This formulation
seems reasonable, but it is still a model—an abstract mathematical description—and not the
real thing. Compare the simple state description we have chosen, In(Arad), to an actual cross country
trip, where the state of the world includes so many things: the traveling companions,
the current radio program, the scenery out of the window, the proximity of law enforcement
officers, the distance to the next rest stop, the condition of the road, the weather, and so on.
All these considerations are left out of our state descriptions because they are irrelevant to the
problem of finding a route to Bucharest. The process of removing detail from a representation
is called abstraction.