Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
What is not a property will be a difference: it is, for instance, one thing to be a slave, and another to be in a state of servitude; hence the distinction raised in connexion with persons assigned to their creditors for debt: A slave, if he is manumitted becomes a freedman, but this is not the case with one who is assigned. There are also other points of difference which are dealt with elsewhere. [*](VII. iii. 26. Also III vi. 25.)
Again, the term difference is applied in cases when the genus is divided into species and one species is subdivided. Animal, for instance, is a genus, mortal a species, while terrestrial or biped is a difference: for they are not actually properties, but serve to show
which latter he calls form, from definition and includes them under relation. For example, if a person to whom another man has left all his silver should claim all his silver money as well, he would base his claim upon genus; on the other hand if when a legacy has been left to a married woman holding the position of materfamilias, it should be maintained that the legacy is not due to a woman who never came into the power of her husband, the argument is based on species, since there are two kinds of marriage. [*]( There was the formal marriage per coemptionem, bringing the woman under the power ( in manum )of her husband and giving her the title of materfamilias, and the informal marriage based on cohabitation without involving the wife's coming in manum mariti. ) Cicero [*]( Cic. Top. )
further shows that definition is assisted by division, which he distinguishes from partition, making the latter the dissection of a whole into its parts and the former the division of a genus into its forms or species. The number of parts he regards as being uncertain, as for instance the elements of which a state consists; the forms or species are, however, certain, as for instance the number of forms of government, which we are told are three, democracy, oligarchy, and monarchy. It is true that he does not use these illustrations,
since, as he was writing to Trebatius, [*]( A famous lawyer, cp. III. xi. 18. v. 17. ) he preferred to draw his examples from law. I have chosen my illustrations as being more obvious. Properties have relation to questions of fact as well; for instance, it is the property of a good man to act rightly, of an angry man to be violent in speech or action, and consequently we believe that such acts are committed by persons of the appropriate character, or
In a similar way division is valuable both for proof and refutation. For proof, it is sometimes enough to establish one thing.
To be a citizen, a man must either have been born or made such.For refutation, both points must be disproved:
he was neither born nor made a citizen.
This may be done in many ways, and constitutes a form of argument by elimination, whereby we show sometimes that the whole is false, sometimes that only that which remains alter the process of elimination is true. An example of the first of these two cases would be:
You say that you lent him money. Either you possessed it yourself, received it from another, found it or stole it. If you did not possess it, receive it from another, find or steal it, you did not lend it to him.
The residue after elimination is shown to be true as follows:
This slave whom you claim was either born in your house or bought or given you or left you by will or captured from the enemy or belongs to another.By the elimination of the previous suppositions he is shown to belong to another. This form of argument is risky and must be employed with care; for if, in setting forth the alternatives, we chance to omit one, our whole case will fail, and our audience will be moved to laughter. It is safer to do what Cicero [*](pro Caec. xiii. 37. )
does in the pro Caecina, when he asks,
If this is not the point at issue, what is?For thus all other points are eliminated at one swoop. Or again two contrary propositions may be advanced, either of which if established would suffice
There can be no one so hostile to Cluentius as not to grant me one thing: if it be a fact that the verdict then given was the result of bribery, the bribes must have proceeded either from Habitus or Oppianicus: if I show that they did not proceed from Habitus I prove that they proceeded from Oppianicus: if I demonstrate that they were given by Oppianicus, I clear Habitus.