LII. Discourse is divided into five heads; one of which heads is that which statesmen employ when they speak in the public assemblies; and this is called political. Another division is that which orators use in their written harangues, and bring forward for the sake of display in panegyrics or reproaches, or impeachments. And such a description of discourse as this is the rhetorical. A third class is that which private individuals use when conversing with one another. This is called private discourse. Another kind is that which is employed when men converse by means of putting short questions and giving brief answers to those who question them. This is called the dialectic kind of discourse. The fifth division is that which artists adopt when conversing on their own particular art, and this is called professional discourse. Thus discourse, then, is divided into political, rhetorical, private, dialectic, and professional. LIII. Music again is divided into three species. For there is the music of the mouth alone, such as song; secondly, there is the music which is performed by the hands and mouth together, such as singing to the harp; thirdly, there is that which is executed by the hands alone, such as harp playing. Music, therefore, is divided into music of the mouth, music of the mouth and hands, and music of the hands. LIV. Nobleness of birth is divided into four species; the first is when one’s ancestors are noble, and valiant, and just; in which case they say that their posterity are nobly born. The second kind is when one’s ancestors have been princes and rulers of nations, and their posterity also we call noble. Another kind is when one’s ancestors have been distinguished for personal renown, such, for instance, as is gained by generalship or by victory at the games. For their offspring also we address as nobly born. And the last kind is when a man is himself noble in his spirit, and magnanimous. For that man also we call noble, and this is the last kind of nobility. There is, therefore, nobility arising from virtuous ancestors, from royal ancestors, from illustrious ancestors, and from one’s own excellent qualities. LV. Beauty also is divided into three kinds. For there is one kind which is praiseworthy, as that of a beautiful face. Another which is useful, as an instrument or a house, and things of that kind which are beautiful, with reference to our use of them. There is also a beauty with reference to laws, and habits, and things of that kind, which is likewise beautiful, because of its utility. So that beauty again is looked at in three ways, with reference to its praise, its utility, and to our use of it.