The Lives and Opinions of Eminent Philosophers Diogenes Laërtius (first ebook reader .TXT) 📖

one can see the work which is produced by it. Political science, and the science of playing the flute, or the harp, or such things as that, is practical; for one cannot see any visible result which has been produced by them, and yet they are doing something. For one man plays the flute or plays the harp, and another occupies himself with state affairs. Again, geometrical, and harmonic, and astronomical science are all theoretical; for they do nothing, and produce nothing. But the geometrician theorizes as to what relation lines bear to one another, and the harmonist speculates about sounds, and the astronomer about stars and about the world. Accordingly, of sciences some are theoretical, others productive, and a third species is practical.

Of medical science there are five species: one, pharmaceutical; a second, manual; a third, conversant about the regulation of the manner of life and the diet; a fourth, the business of which is to detect diseases; and the fifth is remedial. The pharmaceutical relieves infirmities by means of medicines; the manual heals men by cutting and cauterizing; the one which attends to the diet gets rid of diseases by altering and regulating the diet; the fourth produces its effects by a thorough comprehension of the nature of the disease; and the last relieves men from suffering by bringing prompt assistance at the moment. Medical science, then, is divided into the pharmaceutical, the manual, the dietetic, the diagnostic, and the remedial.

Of law there are two divisions: For there is a written and an unwritten law. The one by which we regulate our constitutions in our cities is the written law; that which arises from custom is the unwritten law. As, for instance, for a man to come naked into the marketplace or to wear woman’s clothes, are actions which are not prohibited by any law, and yet we never do them because they are forbidden by the unwritten law. Law, therefore, is divided into the written and the unwritten law.

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.

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.

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.

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.

The soul is divided into three parts: for one part of it is capable of reason, another is influenced by appetite, the third part is liable to passion. Of these the reasoning part is the cause of deliberating, and reasoning, and understanding, and everything of that kind. The appetite part is that portion of the soul which is the cause of desiring to eat, and to embrace and things of that kind. The passionate part is the cause of men feeling confidence and delight, and grief and anger. The soul therefore is divided into the reasoning part, the appetitive part, and the passionate part.

Of perfect virtue there are four species: One is prudence, one is justice, the third is manly gallantry, and the fourth is temperance. Of these, prudence is the cause of a man acting rightly in affairs; justice is the cause of his acting justly in partnerships and bargains; manly gallantry is the cause of a man’s not being alarmed amid dangers and formidable circumstances, but standing firm; and temperance is the cause of his subduing his appetites, and being enslaved by no pleasure, but living decorously. So that virtue is divided into prudence, justice, manly gallantry, and temperance.

Rule is divided into five parts: One is rule according to law; another is rule according to nature; a third