7. Another line of proof is secured by defining your terms. Thus, 'What is the supernatural? Surely it is either a god or the work of a god. Well, any one who believes that the work of a god exists, cannot help also believing that gods exist.' Or take the argument of Iphicrates, 'Goodness is true nobility; neither Harmodius nor Aristogeiton had any nobility before they did a noble deed'. He also argued that he himself was more akin to Harmodius and Aristogeiton than his opponent was. 'At any rate, my deeds are more akin to those of Harmodius and Aristogeiton than yours are'. Another example may be found in the Alexander. 'Every one will agree that by incontinent people we mean those who are not satisfied with the enjoyment of one love.' A further example is to be found in the reason given by Socrates for not going to the court of Archelaus. He said that 'one is insulted by being unable to requite benefits, as well as by being unable to requite injuries'. All the persons mentioned define their term and get at its essential meaning, and then use the result when reasoning on the point at issue.
8. Another line of argument is founded upon the various senses of a word. Such a word is 'rightly', as has been explained in the Topics.
Another line is based upon logical division. Thus, 'All men do wrong from one of three motives, A, B, or C: in my case A and B are out of the question, and even the accusers do not allege C'.
10. Another line is based upon induction. Thus from the case of the woman of Peparethus it might be argued that women everywhere can settle correctly the facts about their children. Another example of this occurred at Athens in the case between the orator Mantias and his son, when the boy's mother revealed the true facts: and yet another at Thebes, in the case between Ismenias and Stilbon, when Dodonis proved that it was Ismenias who was the father of her son Thettaliscus, and he was in consequence always regarded as being so. A further instance of induction may be taken from the Law of Theodectes:
'If we do not hand over our horses to the care of men who have mishandled other people's horses, nor ships to those who have wrecked other people's ships, and if this is true of everything else alike, then men who have failed to secure other people's safety are not to be employed to secure our own.' Another instance is the argument of Alcidamas: 'Every one honours the wise'. Thus the Parians have honoured Archilochus, in spite of his bitter tongue; the Chians Homer, though he was not their countryman; the Mytilenaeans Sappho, though she was a woman; the Lacedaemonians actually made Chilon a member of their senate, though they are the least literary of men; the Italian Greeks honoured Pythagoras; the inhabitants of Lampsacus gave public burial to Anaxagoras, though he was an alien, and honour him even to this day. (It may be argued that peoples for whom philosophers legislate are always prosperous) on the ground that the Athenians became prosperous under Solon's laws and the Lacedaemonians under those of Lycurgus, while at Thebes no sooner did the leading men become philosophers than the country began to prosper.
11. Another line of argument is founded upon some decision already pronounced, whether on the same subject or on one like it or contrary to it. Such a proof is most effective if every one has always decided thus; but if not every one, then at any rate most people; or if all, or most, wise or good men have thus decided, or the actual judges of the present question, or those whose authority they accept, or any one whose decision they cannot gainsay because he has complete control over them, or those whom it is not seemly to gainsay, as the gods, or one's father, or one's teachers. Thus Autocles said, when attacking Mixidemides, that it was a strange thing that the Dread Goddesses could without loss of dignity submit to the judgement of the Areopagus, and yet Mixidemides could not. Or as Sappho said, 'Death is an evil thing; the gods have so judged it, or they would die'. Or again as Aristippus said in reply to Plato when he spoke somewhat too dogmatically, as Aristippus thought: 'Well, anyhow, our friend', meaning Socrates, 'never spoke like that'. And Hegesippus, having previously consulted Zeus at Olympia, asked Apollo at Delphi 'whether his opinion was the same as his father's', implying that it would be shameful for him to contradict his father. Thus too Isocrates argued that Helen must have been a good woman, because Theseus decided that she was; and Paris a good man, because the goddesses chose him before all others; and Evagoras also, says Isocrates, was good, since when Conon met with his misfortune he betook himself to Evagoras without trying any one else on the way.
12. Another line of argument consists in taking separately the parts of a subject. Such is that given in the Topics: 'What sort of motion is the soul? for it must be this or that.' The Socrates of Theodectes provides an example: 'What temple has he profaned? What gods recognized by the state has he not honoured?'
13. Since it happens that any given thing usually has both good and bad consequences, another line of argument consists in using those consequences as a reason for urging that a thing should or should not be done, for prosecuting or defending any one, for eulogy or censure. E.g. education leads both to unpopularity, which is bad, and to wisdom, which is good. Hence you either argue, 'It is therefore not well to be educated, since it is not well to be unpopular': or you answer, 'No, it is well to be educated, since it is well to be wise'. The Art of Rhetoric of Callippus is made up of this line of argument, with the addition of those of Possibility and the others of that kind already described.
14. Another line of argument is used when we have to urge or discourage a course of action that may be done in either of two opposite ways, and have to apply the method just mentioned to both.
