 The distinction between heterogeneous and homogeneous parts is bequeathed to medieval philosophers by Aristotle and Boethius. Aristotle imposes a loose hierarchy on these types of parts, claiming that the heterogeneous parts are composed out of homogeneous parts (History of Animals 486a13–14). This in turn suggests that the division of a whole into its parts is best initiated by dividing it into its heterogeneous parts, and only then into its homogeneous parts. Boethius is less explicit, suggesting that there may be many equally acceptable ways to begin to divide up a thing into its parts (On Division 888a-b). 