 It must be admitted, I think, that when stated in the abstract there is a certain beauty about the structure of Aristotle’s two classificatory schemes. Aristotle’s system, however, begins to look somewhat awkward when his list of highest kinds is scrutinized. Some of the categories are natural, but others seem much less so. As a result, philosophers have proposed changes to Aristotle’s list, arguing that various categories should be eliminated, and scholars have suggested that Aristotle’s categories are not merely the highest kinds but rather represent various complex relations between words and different aspects of the world. A brief discussion of the first four categories, which are the only ones that Aristotle discusses at length, should bring out both the interest of Aristotle’s list as well as some of its peculiarities.