THE ROLE OF REASONING IN CONSTRUCTING A PERSUASIVE ARGUMENT

RICHARD R. ORSINGER

[email protected] http://www.orsinger.com McCurley, Orsinger, McCurley, Nelson & Downing, L.L.P.

San Antonio Office: 1717 Tower Life Building San Antonio, Texas 78205 (210) 225-5567 http://www.orsinger.com and Dallas Office: 5950 Sherry Lane, Suite 800 Dallas, Texas 75225 (214) 273-2400 http://www.momnd.com

State Bar of Texas 37TH ANNUAL ADVANCED FAMILY LAW COURSE August 1-4, 2011 San Antonio

CHAPTER 11

The Role of Reasoning in Constructing a Persuasive Argument Chapter 11

Table of Contents

I. THE IMPORTANCE OF PERSUASION...... 1 II. PERSUASION IN ARGUMENTATION...... 1 III. BACKGROUND...... 2 IV. USER’S GUIDE FOR THIS ARTICLE...... 2 V. ARISTOTLE’S THREE COMPONENTS OF A PERSUASIVE SPEECH...... 3 A. ETHOS...... 3 B. PATHOS...... 4 C. LOGOS...... 4 1. Syllogism...... 4 2. Implication...... 4 3. Enthymeme...... 4 (a) Advantages and Disadvantages of Commonplaces...... 5 (b) Selection of Commonplaces...... 5 VI. ARGUMENT MODELS (OVERVIEW)...... 5 A. LOGIC-BASED ARGUMENTS...... 5 1. Deductive Logic...... 5 2. Inductive Logic...... 6 3. Reasoning by Analogy...... 7 B. DEFEASIBLE ARGUMENTS...... 7 C. THE TOULMIN ARGUMENTATION MODEL...... 7 D. FALLACIOUS ARGUMENTS...... 8 E. ARGUMENTATION SCHEMES...... 8 VII. LOGICAL REASONING (DETAILED ANALYSIS)...... 8 A. DEDUCTIVE REASONING...... 8 1. The Categorical Syllogism...... 8 a. Graphically Depicting the Simple Categorical Syllogism...... 9 b. A Legal Dispute as a Simple Syllogism...... 9 c. Disputed Facts; Disputed Law...... 9 2. The Hypothetical Syllogism...... 10 a. The Conditional Syllogism...... 10 b. The Conjunctive Syllogism...... 10 c. The Disjunctive Syllogism...... 10 3. The Dilemma...... 10 4. Implication...... 10 a. Antecedent/Consequent...... 11 b. Two Rules of Implication and Three Points to Remember...... 11 c. Affirming the Antecedent (Modus Ponens)...... 12 d. Denying the Consequent (Modus Tollens)...... 12 e. Chaining Conditional Propositions...... 12 f. Enthymemes...... 13 g. Proof by Contradiction...... 13 h. Proof by Contrapositive...... 14 i. Disproof by Counterexample...... 14

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j. Attacking a Conditional Proposition...... 14 k. Refuting a Deductive Argument...... 14 l. Refuting an Argument for Change...... 15 m. Refuting an Argument Over Trust Income...... 15 B. INDUCTIVE REASONING...... 15 1. Generalization...... 15 2. Simple Induction...... 15 3. Correlation and Causation...... 15 4. Statistical Syllogism...... 15 5. Statistical Prediction...... 16 6. The Counting Marbles Example...... 16 7. Counterexamples in Inductive Reasoning...... 16 8. Cognitive Studies of Inductive Reasoning...... 16 9. Generating Rules to Resolve Legal Cases...... 16 C. REASONING BY ANALOGY...... 17 1. Terms of Analogical Reasoning...... 18 2. Comparing Deductive, Inductive and Analogical Reasoning...... 19 3. The Process of Analogical Reasoning...... 20 a. Retrieval...... 20 b. Mapping...... 20 c. Projection...... 21 d. Evaluating the Analogy...... 21 4. The Use of Examples...... 21 5. Arguments by Analogy...... 21 6. Judging the Validity of an Analogy...... 22 7. Using Analogical Reasoning With Case Law...... 23 8. Analogies are More Than Just Words...... 23 9. The Power of Metaphors In the Law...... 24 VIII. DEFEASIBLE ARGUMENTS (DETAILED ANALYSIS)...... 25 A. NOT TRUTH, BUT PRIMA FACIE ACCEPTABILITY...... 26 B. DEFEASIBLE ARGUMENTS IN LAW...... 26 IX. THE TOULMIN ARGUMENTATION MODEL (DETAILED ANALYSIS)...... 28 A. THE MAN AND THE TIMES...... 28 B. OVERVIEW OF TOULMIN’S MODEL...... 29 C. THE COMPONENTS OF THE TOULMIN MODEL...... 30 1. Claims...... 30 2. Grounds...... 31 3. Warrants...... 31 4. Backing...... 31 5. Qualifiers...... 31 6. Rebuttals...... 31 D. THE TOULMIN ARGUMENTATION MODEL...... 32 E. ARGUMENTATION IS A PROCESS...... 32 X. FALLACIOUS ARGUMENTS (DETAILED ANALYSIS)...... 32 A. FALLACIES OF DEDUCTIVE REASONING...... 32

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1. The Fallacy of Four Terms...... 33 2. The Fallacy of the Undistributed Middle Term...... 33 3. The Fallacy of Illicit Process of the Major or Illicit Minor Term...... 33 4. The Fallacy of Negative Premises...... 34 5. The Fallacy of Drawing Affirmative Conclusions From a Negative Premise...... 34 6. The Existential Fallacy...... 34 7. The Fallacy of Denying the Antecedent...... 34 8. The Fallacy of Affirming the Consequent...... 34 9. The Fallacy of False Dilemma...... 35 10. Accident...... 35 11. Ignorance of Refutation...... 35 12. Inconsistency...... 35 13. Non Sequitur...... 36 14. Slippery Slope...... 36 15. Begging the Question...... 37 16. Circular Reasoning...... 37 17. Changing the Premises...... 37 B. FALLACIES OF INDUCTIVE REASONING...... 37 1. Hasty Generalization...... 37 2. Fallacies of Distribution...... 37 a. Fallacy of Composition...... 37 b. Fallacy of Division...... 37 3. Dicto Simpliciter...... 37 4. False Cause...... 38 5. Suppressed Evidence...... 39 6. Overwhelming Exception...... 39 7. Common Statistical Fallacies...... 39 a. Errors in Generating Statistics...... 39 (1) Sampling Bias...... 39 b. Errors in Interpreting Statistics...... 39 (1) Fallacy of Small Sample...... 39 (2) Base Rate Fallacy...... 39 (3) Ignoring Regression to the Mean...... 39 (4) Conjunction Fallacy...... 39 (5) Gambler’s Fallacy...... 40 (6) Texas Sharpshooter Fallacy...... 40 C. FALLACIES OF ANALOGICAL REASONING...... 40 1. False Analogy...... 40 D. FALLACIES OF ARGUMENTATION...... 40 1. Accent...... 41 2. Ambiguity...... 41 3. Amphiboly...... 41 4. Appeal to Authority (ad Verecundiam)...... 41 5. Appeal to Belief...... 42 6. Appeal to Emotion...... 42

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7. Appeal to Fear (ad Baculum)...... 42 8. Appeal to Flattery...... 42 9. Appeal to Novelty...... 42 10. Appeal to Pity (ad Misericordiam)...... 43 11. Appeal to Ridicule...... 43 12. Appeal to Tradition...... 43 13. Argumentum ad Hominem...... 43 14. Argumentum Ad Hominem Tu Quoque...... 43 15. Argument From Fallacy (ad Logicano)...... 43 16. Argument from Ignorance (ad Ignorantiam)...... 43 17. Argument From Popular Appeal (ad Populum)...... 44 18. Argument to Moderation (ad Temperantiam)...... 44 19. Bandwagon Effect...... 44 20. Complex Question...... 44 21. Converse Accident...... 44 22. Equivocation...... 44 23. False Compromise...... 44 24. Genetic Fallacy...... 44 25. Guilt by Association...... 44 26. Insignificance...... 45 27. Irrelevant Conclusion (Ignoratio Elenchi)...... 45 28. Many Questions...... 45 29. Misapplied Burden of Proof...... 45 30. Misleading Vividness...... 45 31. Moving the Goalposts...... 45 32. No-True-Scotsman Fallacy...... 45 33. Poisoning the Well...... 45 34. Questionable Cause...... 45 35. Special Pleading...... 45 36. Red Herring...... 45 37. Relativist Fallacy...... 46 38. Repetition...... 46 39. Silence as Assent...... 46 40. Straw Man...... 46 41. Style Over Substance...... 46 E. OTHER CATEGORIZATIONS OF FALLACIES...... 46 1. Aristotle’s Fallacies...... 46 2. Francis Bacon’s Fallacies...... 47 3. John Stuart Mills’ Fallacies...... 47 XI. ARGUMENTATION SCHEMES (DETAILED ANALYSIS)...... 47 A. THE STRUCTURE OF AN ARGUMENTATION SCHEME...... 48 B. ARGUMENTATION SCHEMES FOR TYPES OF REASONING...... 48 1. Deductive Reasoning...... 48 a. Categorical Syllogism...... 49 b. Disjunctive Syllogism...... 49

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c. Hypothetical Syllogism...... 49 d. Deductive Modus Ponens...... 50 e. Deductive Modus Tollens...... 50 f. Indirect Proof...... 50 g. Reductio ad Absurdum...... 51 2. Inductive Reasoning...... 52 a. Argument from a Random Sample to a Population...... 52 3. Analogical Reasoning...... 52 a. Argument From Analogy...... 52 b. Argument From Precedent...... 53 4. Practical Reasoning...... 53 a. Argument from Consequences...... 53 b. Argument from Waste, or Sunk Costs Argument...... 54 5. Abductive Reasoning...... 54 a. Argument from Sign...... 54 6. Causal Reasoning...... 54 a. Argument from Cause to Effect...... 55 b. Argument from Correlation to Cause...... 55 c. Causal Slippery Slope Argument...... 55 C. SOURCE-BASED ARGUMENTS...... 55 1. Argument From Authority...... 55 2. Argument From Position to Know...... 56 a. Argument From Witness Testimony...... 56 b. Argument From Expert Opinion...... 56 c. Argument From Ignorance...... 59 3. Arguments From Commitment...... 60 a. Argument From Inconsistent Commitment...... 60 4. Arguments Attacking Personal Credibility...... 60 a. Ad Hominem Arguments...... 60 5. Arguments From General Acceptance...... 61 a. Argument From Generally Accepted Opinion...... 61 b. Argument From General Practice...... 62 D. APPLYING RULES TO CASES...... 62 1. Arguments Based on Cases...... 62 a. Argument From Example...... 62 b. Argument From Analogy...... 63 c. Argument From Precedent...... 63 2. Defeasible Rule-Based Arguments...... 63 a. Argument From an Established Rule...... 63 b. Argument from an Exceptional Case...... 63 3. Verbal Classification Arguments...... 63 a. Argument From Verbal Classification...... 63 b. Argument From Vagueness of a Verbal Classification...... 64 c. Argument From Definition to Verbal Classification...... 64 4. Chained Arguments Connecting Rules and Cases...... 64

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a. Argument From Gradualism...... 64 b. Precedent Slippery Slope Argument...... 64 c. Slippery Slope Argument...... 64 XII. PRIMA FACIE EVIDENCE, PRESUMPTIONS, AND THE BURDEN OF PROOF...... 65 1. Understanding Prima Facie Evidence...... 65 2. Presumptions and Burdens of Proof...... 68 a. Presumptions That Fix the Burden of Persuasion...... 68 b. Burden of Producing Evidence...... 69 (1) Special Appearance...... 69 (2) Summary Judgment...... 69 (3) Child Support for Underemployed...... 70 (4) Establishing Privilege...... 70 (5) Spoliation Instruction...... 70 (6) Trespass on Real Property...... 70 3. The California Legislature Shines a Light on the Subject...... 70 4. The Continued Vitality of Prima Facie Evidence as a Control Device...... 71

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