Of means of persuading by speaking there are three species: some consist in the character of the speaker; others in the disposing the hearer a certain way; others in the thing itself which is said, by reason of its proving, or appearing to prove the point.
For the real difference between humans and other animals is that humans alone have perception of good and evil, just and unjust, etc. It is the sharing of a common view in these matters that makes a household and a state.
The beginning of reform is not so much to equalize property as to train the noble sort of natures not to desire more, and to prevent the lower from getting more.
Now the greatest external good we should assume to be the thing which we offer as a tribute to the gods, and which is most coveted by men of high station, and is the prize awarded for the noblest deeds; and such a thing is honor, for honor is clearly the greatest of external goods.
But a man's best friend is the one who not only wishes him well but wishes it for his own sake (even though nobody will ever know it): and this condition is best fulfilled by his attitude towards himself - and similarly with all the other attributes that go to define a friend. For we have said before that all friendly feelings for others are extensions of a man's feelings for himself.
Plants, again, inasmuch as they are without locomotion, present no great variety in their heterogeneous pacts. For, when the functions are but few, few also are the organs required to effect them. ... Animals, however, that not only live but perceive, present a great multiformity of pacts, and this diversity is greater in some animals than in others, being most varied in those to whose share has fallen not mere life but life of high degree. Now such an animal is man.
Again, the male is by nature superior, and the female inferior; and the one rules, and the other is ruled; this principle, of necessity, extends to all mankind.
The same thing may have all the kinds of causes, e.g. the moving cause of a house is the art or the builder, the final cause is the function it fulfils, the matter is earth and stones, and the form is the definitory formula.
Tools may be animate as well as inanimate; for instance, a ship's captain uses a lifeless rudder, but a living man for watch; for a servant is, from the point of view of his craft, categorized as one of its tools. So any piece of property can be regarded as a tool enabling a man to live, and his property is an assemblage of such tools; a slave is a sort of living piece of property; and like any other servant is a tool in charge of other tools.