Philodemus in On Vices paraphrases and quotes Aristo on the appearances and consequences of arrogance, including several definitions and sketches of character types related to the arrogant man (αυθάδης). Here I shall investigate the tradition of character studies in which Aristo stands, taking into account criteria of form, style, and technique as well as the content of two exemplary sketches. The main focus will be on the purposes of texts that provide what I call “conceptual” and “inferential” definitions.