The seemingly bizarre conclusions that the prime movers are objects of desire for the heavens and that they occupy themselves by contemplating contemplation are consequences of Aristotle’s claim that prime movers themselves are unmoved. Aristotle wants the prime movers to be unmoved for fear of an infinite regress: if they are moved, we can ask what moves them, and then ask what moves their movers, and so on. However, according to Aristotle’s theory of causation, something cannot cause another thing to move unless it imparts movement to that other thing. A person cannot move a box without pushing or pulling on it. The only cause of motion that seems not to require movement is desire. If the prime movers were to push the heavens in their circular movements, they would themselves be moving, but if the heavens move in a circular pattern out of a desire for the perfection of the prime movers, this does not call for any movement on the part of the prime movers. This, of course, raises the question of what makes the prime movers so perfect that the heavens should move for them, and for reasons previously outlined, Aristotle concludes that they engage in the perfect activity of contemplating contemplation.