Book 2
25.1
Next to what has been said we must speak of refutation. An argument may be refuted either by a counter-syllogismIn which the contrary of an opponent's conclusion is proved. or by bringing an objection.
25.2
It is clear that the same topics may furnish counter-syllogisms; for syllogisms are derived from probable materials and many probabilities are contrary to one another.
25.3
An objection is brought, as shown in the Topics, in four ways: it may be derived either from itself,i.e., the opponent's enthymeme. or from what is similar, or from what is contrary, or from what has been decided.
25.4
In the first case, if for instance the enthymeme was intended to prove that love is good, two objections might be made; either the general statement that all wantLove is regarded as a desire, and therefore as bad as any other desire. It is here included under the general head of want. is bad, or in particular, that Caunian loveIncest: Ovid Met. 9.454. would not have become proverbial, unless some forms of love had been bad.
25.5
An objection from what is contrary is brought if, for instance, the enthymeme is that the good man does good to all his friends; it may be objected: But the bad man does not do harm [to all his friends].The contrary of good men do good to all their friends is bad men do harm to all their friends, but this is not always true. Jebb gives the objection as: No, the bad man does not do evil to all his enemies.
