What kind of mental state does the meditation on four elements generate?

In the Maha-satipatthana Sutta (DN22), the mindfulness about the elements is taught: > “There are in this body, the earth element, the water element, the > fire element, the wind element.” > > Just as though, monks, a clever butcher, or a butcher’s apprentice, > after slaughtering a cow, were sitting down at a crossroads after > dividing it into portions; even so, monks, a monk in regard to this > very body, however placed, however disposed, reflects by way of the > elements: > “There are in this body, the earth element, the water element, the > fire element, the wind element.” However I am unable to understand why we have to look at the elements from the clever butcher's point of view. What kind of mental state does the meditation on elements generate? Please explain the analogy in detail.