[jerf]

It's kinda hard to sit down and formulate a "rational actor" that has no emotions or drives or goals, and put that into any sort of useful theory of the world. You end up calling rocks rational actors when they, having no goals or negative stimuli, "rationally" sit there and do nothing. (Which may be "true" in some sense, but isn't a terribly useful definition.)

Rationality is more about how goals are obtained than what those goals are. The latter can still play a part (e.g., are the goals coherent? that's a proper question for rationality), but it's lesser.