The Collected Works of Dale Carnegie. Dale Carnegie

common sense, it will lose its terrors. In fact, logic[25] is a fascinating subject, well worth the public speaker's study, for it explains the principles that govern the use of argument and proof.

      Argumentation is the process of producing conviction by means of reasoning. Other ways of producing conviction there are, notably suggestion, as we have just shown, but no means is so high, so worthy of respect, as the adducing of sound reasons in support of a contention.

      Since more than one side of a subject must be considered before we can claim to have deliberated upon it fairly, we ought to think of argumentation under two aspects: building up an argument, and tearing down an argument; that is, you must not only examine into the stability of your structure of argument so that it may both support the proposition you intend to probe and yet be so sound that it cannot be overthrown by opponents, but you must also be so keen to detect defects in argument that you will be able to demolish the weaker arguments of those who argue against you.

      We can consider argumentation only generally, leaving minute and technical discussions to such excellent works as George P. Baker's "The Principles of Argumentation," and George Jacob Holyoake's "Public Speaking and Debate." Any good college rhetoric also will give help on the subject, especially the works of John Franklin Genung and Adams Sherman Hill. The student is urged to familiarize himself with at least one of these texts.

      The following series of questions will, it is hoped, serve a triple purpose: that of suggesting the forms of proof together with the ways in which they may be used; that of helping the speaker to test the strength of his arguments; and that of enabling the speaker to attack his opponent's arguments with both keenness and justice.

      TESTING AN ARGUMENT

       I. The Question Under Discussion

       1. Is it clearly stated? (a) Do the terms of statement mean the same to each disputant? (For example, the meaning of the term "gentleman" may not be mutually agreed upon.) (b) Is confusion likely to arise as to its purpose? 2. Is it fairly stated? (a) Does it include enough? (b) Does it include too much? (c) Is it stated so as to contain a trap? 3. Is it a debatable question? 4. What is the pivotal point in the whole question? 5. What are the subordinate points? II. The Evidence 1. The witnesses as to facts (a) Is each witness impartial? What is his relation to the subject at issue? (b) Is he mentally competent? (c) Is he morally credible? (d) Is he in a position to know the facts? Is he an eye-witness? (e) Is he a willing witness? (f) Is his testimony contradicted? (g) Is his testimony corroborated? (h) Is his testimony contrary to well-known facts or general principles? (i) Is it probable? 2. The authorities cited as evidence (a) Is the authority well-recognized as such? (b) What constitutes him an authority? (c) Is his interest in the case an impartial one? (d) Does he state his opinion positively and clearly? (e) Are the non-personal authorities cited (books, etc.) reliable and unprejudiced? 3. The facts adduced as evidence (a) Are they sufficient in number to constitute proof? (b) Are they weighty enough in character? (c) Are they in harmony with reason? (d) Are they mutually harmonious or contradictory? (e) Are they admitted, doubted, or disputed? 4. The principles adduced as evidence (a) Are they axiomatic? (b) Are they truths of general experience? (c) Are they truths of special experience? (d) Are they truths arrived at by experiment? Were such experiments special or general? Were the experiments authoritative and conclusive? III. The Reasoning 1. Inductions (a) Are the facts numerous enough to warrant accepting the generalization as being conclusive? (b) Do the facts agree only when considered in the light of this explanation as a conclusion? (c) Have you overlooked any contradictory facts? (d) Are the contradictory facts sufficiently explained when this inference is accepted as true? (e) Are all contrary positions shown to be relatively untenable? (f) Have you accepted mere opinions as facts? 2. Deductions (a) Is the law or general principle a well-established one? (b) Does the law or principle clearly include the fact you wish to deduce from it, or have you strained the inference? (c) Does the importance of the law or principle warrant so important an inference? (d) Can the deduction be shown to prove too much? 3. Parallel cases (a) Are the cases parallel at enough points to warrant an inference of similar cause or effect? (b) Are the cases parallel at the vital point at issue? (c) Has the parallelism been strained? (d) Are there no other parallels that would point to a stronger contrary conclusion? 4. Inferences (a) Are the antecedent conditions such as would make the allegation probable? (Character and opportunities of the accused, for example.) (b) Are the signs that point to the inference either clear or numerous enough to warrant its acceptance as fact? (c) Are the signs cumulative, and agreeable one with the other? (d) Could the signs be made to point to a contrary conclusion? 5. Syllogisms (a) Have any steps been omitted in the syllogisms? (Such as in a syllogism in enthymeme.) If so, test any such by filling out the syllogisms. (b) Have you been guilty of stating a conclusion that really does not follow? (A non sequitur.) (c) Can your syllogism be reduced to an absurdity? (Reductio ad absurdum.)

      QUESTIONS AND EXERCISES

      1. Show why an unsupported assertion is not an argument.

      2. Illustrate how an irrelevant fact may be made to seem to support an argument.

      3. What inferences may justly be made from the following?

      During the Boer War it was found that the average Englishman did not measure up to the standards of recruiting and the average soldier in the field manifested a low plane of vitality and endurance. Parliament, alarmed by the disastrous consequences, instituted an investigation. The commission appointed brought in a finding that alcoholic poisoning was the great cause of the national degeneracy. The investigations of the commission have been supplemented by investigations of scientific bodies and individual scientists, all arriving at the same conclusion. As a consequence, the British Government has placarded the streets of a hundred cities with billboards setting forth the destructive and degenerating nature of alcohol and appealing to the people in the name of the nation to desist from drinking alcoholic beverages. Under efforts directed by the Government the British Army is fast becoming an army of total abstainers.

      The Governments of continental Europe followed the lead of the British Government. The French Government has placarded France with appeals to the people, attributing the decline of the birth rate and increase in the death rate to the widespread use of alcoholic beverages. The experience of the German Government has been the same. The German Emperor has clearly stated that leadership in war and in peace will be held by the nation that roots out alcohol. He has undertaken to eliminate even the drinking of beer, so far as possible, from the German Army and Navy.—Richmond Pearson Hobson, Before the U.S. Congress.

      4. Since the burden of proof lies on him who attacks a position, or argues for a change in affairs, how would his opponent be likely to conduct his own part of a debate?

      5. Define (a) syllogism; (b) rebuttal; (c) "begging the question;" (d) premise; (e) rejoinder; (f) sur-rejoinder; (g) dilemma; (h) induction; (i) deduction; (j) a priori; (k) a posteriori; (l) inference.

      6. Criticise this reasoning:

      Men ought not to smoke tobacco, because to do so is contrary to best medical opinion. My physician has expressly condemned the practise, and is a medical authority in this country.

      7. Criticise this reasoning:

      Men ought not to swear profanely, because it is wrong. It is wrong for the reason that it is contrary to the Moral Law, and it is contrary to the Moral Law because it is contrary to the Scriptures. It is contrary to the Scriptures because it is contrary to the