The Dilemma.—In this method of refutation you show your opponent has only two arguments to advance, that neither of them is true and that therefore his case falls unproved. No better illustration of the effectiveness of this method can be given than a reference to the historic Lincoln-Douglas debates. You will remember that Douglas declared he believed both in squatter sovereignty and in the Dred Scott decision. The one said that the people of any territory had the right to decide for themselves whether they would or would not exclude slavery, while the Dred Scott decision meant that a slaveholder could recover his slave in any territory into which he might escape. You see the two positions are logically inconsistent. When, therefore, Lincoln asked Douglas as he did in these debates, this question, “Can the people of a territory, prior to the formation of a state constitution, in any lawful way exclude slavery?” Douglas was compelled to face a perfect dilemma. If he answered “yes” he would repudiate the Dred Scott decision—he wanted the support of the South. If he answered “no,” he would repudiate the doctrine of squatter sovereignty and offend the North. In endeavoring to meet the difficulty, he maintained that while a territory could not exclude slavery it could legally enact such unfriendly legislation that it would be impossible for slavery to remain. Lincoln practically had Douglas defeated before the judges of that debate—the American people—when he showed the absurdity of Douglas’ attempted escape from his dilemma. Lincoln showed that in effect Douglas said that slavery could lawfully be excluded from a place where it had a lawful right to be. The debate—and this famous “dilemma” was the spectacular part of it—made Lincoln president.
Residues.—This method is simply an enlargement of the difficulties of the dilemma. When more than two possibilities are presented and you demolish one after the other of them your hope is that nothing may be left of his case—that the residuum may be zero.
Analyze Your Opponent’s Case.—As your opponent is speaking, note his points with care. Apply to them the principles we have discussed in earlier chapters.
Is his reasoning based upon premises which you can disprove?
Has he ignored the real issue?
Are his alleged causes merely coincidences, or are there other contributing causes which lessen the force of his conclusion?
Is his observation of facts faulty and are his generalizations unsound and based upon insufficient and unfair instances?
Apply these tests to his arguments and you will render your task of refutation easier. But in your refutation, be sure you refute. Don’t think for a minute that either heat or violence or sarcasm is a good answer. Neither can the testimony of one witness be rebutted by that of another unless the latter’s knowledge of the matter is shown to be the greater. And the strength of refutation lies in the skill with which you make your audience believe your witnesses are more worthy of belief than those of your opponent, provided always that is the fact.