Legal Technique and Logic

LEGAL TECHNIQUE AND LOGIC

finding justice

A. Basics of logic and its application to legal thinking and legal argument Deductive Reasoning  based on the act of proving a conclusion by means of two other propositions.  reasoning in which a conclusion is compelled by known facts  syllogism Syllogism  powerful tool because of its rigid flexibility  Three Parts: a. Major Premise: states a broad and generally applicable truth. b. Minor Premise: states a specific and usually more narrowly applicable truth. c. Conclusion: drawn from the two premises that offers a new insight that is known to be true based on the premises.  Principle: “What is true of the universal is true of the particular.” Inductive Reasoning  anthitesis of deductive  specific conclusions are generalized to general conclusions  multiple particular to general  Principle: “The world is sufficiently regular to permit the discovery of general rules.” B. Civil Law Tradition vs. Common Law Tradition Civil Law Tradition  the law is almost entirely codified, highly systemized and structured and that it relies on broad, general principles, without necessarily setting out the details.  basis of private law; quantified  appear for the most part in reported usually judgments rendered by higher courts. Common Law Tradition  known for its jurisprudence, for a system of legal precepts that emerge from court decisions Differences Sources of Law Principle of precedent & stare decisis Method of legal thinking &

CIVIL LAW Codified Bound to codes & reason

COMMON LAW Judge-made case law Subject to these two principles

Develop abstract

Dominated on focusing on

Function of Doctrine

Appointment of Judges

Procedural

principle & apply to the facts by subsuming Provide all practitioners w/ a guideline for handling & deciding on specific future cases by developing basic rules Appoint young highly skilled but inexperienced graduates Focus on settlement of the dispute

each case Find differences& similarities in decided cases to extract specific rules from decided cases Selected & appointed only from among experienced practicing lawyers Adversarial

“Nullum Crimen Nulla Poena Sine Lege”  there is no crime when there is no law punishing it Precedent  basic ingredient of the common law  narrow rule that emerges from a specific fact situation Stare Decisis  “stare decisis et non quieta movere”  things that are settles should not be disturbed II. Legal Thinking A. Moral, Aesthetic and Legal reasoning 1. Moral reasoning and Moral deliberation Moral Relativism  nobody is objectively right or wrong  culture- based Moral Subjectvism  our own mental activity is the only unquestionable fact of our own experience. Utilitarianism  achieving greatest happiness for the general welfare Duty Theory or Deontologism  moral duty  duty ethics, place the emphasis on adhering to ethical principles or duties

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postulate the existence of moral absolutes that make an action moral

Virtue Ethics  focuses on how to live  how to develop a good character Divine Command Theory  different divine authorities 2. Aesthetic Reasoning  judgments about beauty and art  rely on conceptual frameworks that integrate fact and value Principles: a. Objects are aesthetically valuable if they have a meaning or teach something true.  identifies value in art that fulfills a cultural or social function by teaching that non-art cannot provide. e.g. More happens in one episode of teleserye than what happens to me in one year. b. Objects are aesthetically valuable if they express the values of the culture they arise in, or the artists who make them.  value in art that fulfills cultural or social function. e.g. Homer’s Iliad makes a warrior’s value vivid. c. Objects are aesthetically valuable if they can lead to social change.  social change is an improvement e.g. Noli Me Tangere & El Filibusterismo d. Objects are aesthetically valuable if they give their audience pleasure.  contributes to our happiness, connecting value with a thjng’ s ability to produce a type of psychological experience, aesthetic hedonism. e.g. Fifty Shades of Grey e. Objects are aesthetically valuable if they give their audience certain emotions.  emotions are not daily occurrences e.g. The Lincoln Memorial is awesome. f. Objects are aesthetically valuable if they produce a special nonemotional experience that comes only from art, such as autonomy, or, the willing suspension of disbelief.  comes down to the production of a certain subjective state e.g. Ansel Adam’s photo of Yosemite Valley are breathtaking. g. Objects are aesthetically valuable if they possess a special aesthetic(formal) property, such as beauty, unity, or organization.

 the art object is valuable for itself e.g. Monet’s “waterlilies” series of oil paintings beautifully displaying his obsession with color and design h. Objects are aesthetically valuable because of features that no reasons can determine and no argument can establish.  moral subjectivism; an object is aesthetically valuable if someone values it e.g. She loves the look of her antique bathtub. 3. Legal Reasoning  addresses itself both to the foundation of law in general and to the interpretation of specific laws.  Resembles moral reasoning  Note: Both involve value judgments, though the commands of law come with clear social enforcement behind them Legal Principles: a. Legal Moralism  position that the law should prohibit anything immoral e.g. prostitution should be illegal because it is immoral b. Harm Principle  the law should only prohibit activities that harm others e.g. prostitution would be outlawed because those engaging in it could spread diseases to their unwary partners c. Legal Paternalism  we stop people from behaving a certain way for their own good  prohibits harm to himself/ herself e.g. laws that limit the hours in which bars may open d. Offense Principle  gives a society the right to ban activities that are generally found offensive e.g. Spitting in the streets in Singapore  

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Legal interpretation thus addresses itself to issues of vagueness Many important legal arguments involve an appeal to precedent, in which one uses an established judicial decision to interpret a new case Based on the desire for consistency, the similar treatment of similar situations.

III. The Language of Logic A. Basic Expressions of Logic Case Method Study  study the decisions of the Court because the justices interpret the law  study of the logical method and principles which is used to make decisions

IV. Introduction to Deductive Reasoning and Inductive Reasoning A. 

Socratic Method  dialectical method of teaching Logical Thought  same as reflective thinking  works without emotion  works by comparison, yes or no, either/ or.  Seeks conclusion, decision between two opposing choices  Process that requires some attention to be directed to each step of the process Reflective Thinking  refers to processes of analyzing and making judgments about what has happened Proposition  refers to the content or meaning of a meaningful declarative sentence  includes having the quality or property of being either true or false Term 

part of speech representing something, but which is not true or false in its own right e.g. man, mortal

Deductive Reasoning Two propositions which imply the third proposition, the conclusion, are called premises. The broad proposition that forms the starting point of deduction is called the major premise; the second proposition is called the minor premise. The major premise represents the all; the minor premise, something or someone included in the all.

B.

Inductive Reasoning

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In law, as in general logic, there are fundamental differences between the two types of reasoning:

Deductive Reasoning The connection between a given piece of information and another piece of information concluded from it is a necessary connection. A deductive argument is one whose conclusion is claimed to follow from its premises with absolute necessity. If the premises are valid, the conclusion is valid. If the conclusion is valid, the premises are valid.

Inference  conclusion inferred from the data Implication  the data implies the conclusion Conclusion * it offers a new insight that is known to be true based on the premises. B. Conclusion Testing  a conclusion can be true only when (1) the other proposition are true (2) these propositions imply the conclusion  not all means of persuasion are based on reflective thinking or formal logic  some forms of persuasion are not qualify i.e. rhetoric

In a valid deductive argument, if the premises are true, the conclusion must be true.

Moves by inference from the general (universal) ultimately to the particular.

Inductive Reasoning The connection between given pieces of information and another piece inferred from them is not a logically necessary connection. An inductive argument is one whose conclusion is claimed to follow from its premises only with probability and not absolute necessity. All that is represented is that the conclusion is more probable than not. Its premises do not provide conclusive support for the conclusion; they provide only some support for it. In a valid inductive argument, the conclusion is not necessarily an absolute truth; by induction, we reach a conclusion that is only more probably true than not. Moves from the particular to the general (universal) (induced generalization by enumeration of instances), or from the particular to the particular (analogy).

The core of the difference lies in the strength of the claim that is made about the premises and its conclusion. 1. Inductive Generalization  Formulating a generalization in the law – enumerating a series of tight holdings of cases (legal rules) to create a generalized legal precept (legal principle) – is at best a logic of probabilities. 2. Analogy  Pursuant to the method of analogy, the courts do not generalize certain relevant resemblances and differences between the case at bar and another single case or a relatively small group of cases. V. Deductive Reasoning A. Categorical Syllogism  deductive argument which consists of three categorical propositions, consisting exactly three terms, in which each of the three terms occurs in exactly two of the propositions. 1. Terms a. MAJOR TERM: predicate of the major premise and the conclusion. b. MINOR TERM: predicate of minor premise and the conclusion c. MIDDLE TERM: includes in both premises but not in the conclusion 2. Premises a. MAJOR PREMISE: states a broad and generally applicable truth b. MINOR PREMISE: states a specific and usually more narrowly applicable truth 3. Quantity of Propositions or Terms I. Propositions: a. UNIVERSAL: broad or general b. PARTICULAR: narrow or specific II. Terms a. DISTRIBUTED: broad or general b. UNDISTRIBUTED: narrow or specific 4. Relationship of Classes a. CONTAINMENT: every member of one class is said to be a member of another class b. NO RELATIONSHIP: no member of one class is said to be a member of a second class c. PARTIAL CONTAINMENT: Some, but perhaps not all, members of one class are all said to be members of another class

d. PARTIAL NON- CONTAINMENT: Some, but perhaps not all, members of one class are said not to be members of another class STANDARD FORMS OF CATEGORICAL PROPOSITIONS A: Universal Affirmative E: Universal Negative I: Particular Affirmative O: Particular Negative PROPOSITIO N A E I O

SUBJECT

PREDICATE

D D U U

U D U D

Case: MacPherson v. Buick Motor Co., 227 N.Y. 382, 111 N.E. 1050 (1916) – include Chief Judge Bartlett’s dissenting opinion Enthymeme  an informally stated syllogism with an unstated presumption that must be true for the premises to lead the conclusion a. unstated premise b. unstated conclusion Case: Leliefield v Johnson Polysyllogism  string of any number of propositions forming together a sequence of syllogisms such that the conclusion of each syllogism, together with the next proposition, is a premise for the next, and so on. a. Prosyllogism: the conclusion of which is used as a premise of another syllogism except the last b. Episyllogism: one of the premise of which is the conclusion of a preceding syllogism; validity deals only with form. e.g. It is raining. If we go out while it is raining we will get wet. Therefore, if we go out we will get wet. If we go out we will get wet. If we get wet, we will get cold. Therefore, if we go out we will get cold. SIX RULES OF CATEGORICAL SYLLOGISM 1. A valid CS must contain exactly three terms, each of which is used in the same sense throughout the argument. 2. In a valid CS, the middle term must be distributed in at least one premise.

3. In a valid CS, no term can be distributed in the conclusion which is not distributed in the premise. 4. No CS is valid which has two negative premises. 5. If either premise of a valid CS is negative, the conclusion must be negative. 6. No valid CS with a particular conclusion can have two universal premises. Cases: Morales Development Co., Inc. v. Court of Appeals, et al., G.R. No. L-26572, 28 March 1969 Tavora v. Gavina, G.R. No. L-1257, 30 October 1947, including Resolution dated 11 December 1947 VI. INDUCTIVE REASONING  critical in the common- law tradition; undergirds the doctrine of precedent; like things must be treated alike A. Inductive Generalization (induction by enumeration)  Underlies the development of the common law; from many specific case holdings, a generalized proposition is reached. B.

Analogy  Does not seek proof of an identity of one thing with another, but only a comparison of resemblances. Unlike the technique of enumeration, analogy does not depend upon the quantity of instances, but upon the quality of resemblances between things.  In the law, points of unlikeness are as important as likeness in the cases examined.

Criteria in the appraisal of analogical arguments: 1. The acceptability of the analogy will vary proportionally with the number of circumstances that have been analyzed. 2. The acceptability will depend upon the number of positive resemblances (similarities) and negative resemblances (dissimilarities). 3. The acceptability will be influenced by the relevance of the purported analogies. An argument based on a single relevant analogy connected with a single instance will be more cogent than one which points out a dozen irrelevant resemblances. Cases: MacPherson v. Buick Motor Co., 227 N.Y. 382, 111 N.E. 1050 (1916)

Nielson and Co., Inc. v. Lepanto Consolidated Mining Co., G.R. No. L-21601, 17 December 1966 VIII.

Formal Fallacies

A. Fallacies in Categorical Syllogism 1. The Fallacy of Four Terms (Quaternio Terminorum)  Logical quadruped – argument has more than three terms  When it consists of four terms rather than three because one of the terms is used with two different meanings.  If a term is used in more than one sense, it also violates Rule One; it also constitutes the material fallacy of equivocation (infra).  E.g. A ruler is twelve inches long. King Juan Carlos of Spain is a ruler. Therefore, King Juan Carlos of Spain is twelve inches long. 2. The Fallacy of Undistributed Middle  In order to effectively establish the presence of a genuine connection between the major and minor terms, the premises of a syllogism must provide some information about the entire class designated by the middle term. If the middle term were undistributed in both premises, then the two portions of the designated class of which they speak might be completely unrelated to each other.  E.g. All priests are men. Joey is a man. Joey is a priest 3. The Fallacy of the Illicit Process of the Major Term and Minor Term a. Illicit Major o Major term in the major premise is undistributed but it is distributed in the conclusion; the term is applied to all members of a class in the conclusion even though it was limited to some members of the class in the major premise o E.g. All poets have a creative imagination. No poets are good business people. Therefore, no good business people have a creative imagination. b. Illicit Minor o Minor term in the minor premise is undistributed by is distributed in the conclusion. o E.g. No Negroes are white. Some men are Negroes. Therefore, no men are white.

Case: Suñga, et al. v. Lacson, et al., G.R. No. L26055, 29 April 1968

Fallacy of affirming the consequent b.

4. The Fallacy of Negative Premises/ Exclusive Premises  In an argument consisting of two negative propositions, the middle term is excluded from both the major term and the minor term, and thus there is no connection between the two and no inference can be drawn.  e.g. No dogs are cold-blooded. No coldblooded things are capable of barking. Therefore, no dogs are capable of barking. 5. The Fallacy of Particular Premises (Drawing an affirmative conclusion from a negative premise, or drawing a negative conclusion from an affirmative premise)  An affirmative proposition asserts that one class is included in some way in another class, but a negative proposition that asserts exclusion cannot imply anything about inclusion. For this reason an argument with a negative proposition cannot have an affirmative conclusion. 6. Existential Fallacy  Because we do not assume the existential import of universal propositions, they cannot be used as premises to establish the existential import that is part of any particular proposition. B. Fallacies in Hypothetical Syllogism  Hypothetical Syllogism – this does not directly assert the existence of a fact; instead, it contains a condition, “if”, “unless”, “granted”, “supposing”, etc.  Hypothetical proposition – conditional “ifthen” statement; compound proposition in that every such proposition consists of two component propositions: a. b.

Antecedent – component proposition following “if” Consequent –component proposition following “then”

Forms and fallacies: a. Modus ponens – valid if and only if: i. the categorical premise affirms the antecedent of the conditional premise; and ii. the conclusion affirms the consequent of the conditional premise iii. e.g. If A, then B. A. Therefore, B.

Modus tollens – valid if and only if: i. the categorical premise denies the consequent of the conditional premise; and ii. the conclusion denies the antecedent of the conditional premise iii. e.g If the dogs are noisy then there are intruders in the compound. There are no intruders in the compound. Therefore, the dogs are not noisy. Fallacy of denying the antecedent

C. Fallacies in Disjunctive Syllogism  Disjunctive Syllogism – one premise takes the form of a disjunctive proposition and the other premise and the conclusion are categorical propositions which either deny or affirm part of the disjunctive proposition  Moods of disjunctive syllogism: 1. Mood Which By Denying Affirms – this does not assume that the disjunction asserts two mutually exclusive disjuncts; the disjunctive proposition is not taken to affirm categorically that only one disjunct is true; it says only that at least one disjunct is true, leaving open the possibility that both may be true; not mutually exclusive of one another 2. Mood Which By Affirming Denies – this assumes that the disjunction asserts two mutually exclusive disjuncts; the disjunctive proposition is taken to affirm categorically that only one disjunct is true; mutually exclusive  Fallacies: 1. Fallacy of Missing Disjunctfailure to include all possibilities or alternatives in the major premise; e.g. the jury will either convict or acquit. 2. Fallacy of Nonexclusivity – applies only to the second mood; occurs whenever one assumes that affirming one disjunct shows the other to be false, when in fact it is possible for both to be true IX.

Informal Fallacies

A. Fallacies of Irrelevance and Distraction 1.

Fallacy of Irrelevant Evidence (Ignoratio elenchi) or Fallacy of Missing the Point

 Purports to establish a particular conclusion but is instead directed to proving another conclusion 2.

Fallacies of Distraction  Shift attention from reasoned argument to other things that are irrelevant, irrational and often emotional a. Appeal to Pity (Argumentum ad misericordiam)  Evades the pertinent issues and makes a purely emotional appeal Not a fallacy when relevant to the decision, e.g. equity cases and discretionary sentencing; however, if the question under consideration is a factual issue, an appeal to pity is irrelevant, and deflects attention away from the facts. b. Appeal to Prestige (Argumentum ad verecundiam) or Appeal to Inappropriate Authority  Appeal to authority or prestige of parties having no legitimate claim to authority in the matter at hand  Use of pedantic words and phrases, references, quotations, length, detail and specificity  e.g. Pacquiao said: support the RH bill Lawyers who use too much references,

Case: Neill, J., dissenting, Cresap v. Pacific Inland Navigation Co., 478 P.2d 223, 228 78 Wash.2d 563 (1970)  when the support of the law is not significant per se, its effect is only rhetorical. c. Appeal to Ridicule (Argumentum ad hominem)  Shifts an argument from the point being discussed (ad rem) to irrelevant personal characteristics of an opponent, and makes the opponent the issue  However, ad hominem may be allowed in the use of evidence of both bad character and bias for the purpose of attacking a witness’ credibility. Another proper use is in receiving expert witness testimony. See: Rules of Court Sec. 20 Rule 130 (Witnesses; their qualifications) Sec. 51 Rule 130 (Character evidence not generally admissible; exceptions)

Sec. 11 Rule 132 (Impeachment of adverse party’s witness) Sec. 14 Rule 132 (Evidence of good character of witnesses) Cases:Melvin v. Belen, A.M. No. RTJ-08-2119, 30 June 2008 (conduct of an unbecoming of a judge, attacking the law school the lawyer attended) ; Sy, et al. v. Fineza, A.M. No. RTJ-03-1808, 15 October 2003 (judge settlement fee “bakla”) d. Appeal to the Masses(Argumentum ad populum)  Departs from the question under discussion and attempts to win assent to a proposition by making an appeal to the feelings and prejudices of the multitude Approaches: a. Bandwagon Approach “Everybody is doing it.” b. Patriotic Approach "Draping oneself in the flag.” c. Snob Approach - “All the best people are doing it.” 5. Appeal to the Ages or Tradition (Argumentum ad antiquitam)  Holds that determinations and customs of our fathers and forbears must not be changed 6. Appeal to Novelty, Modernity or Youth (Argumentum ad novitatem)  Claims that an idea or proposal is superior exclusively because it is new and modern 7. Appeal to Terror (Argumentum ad terrorem)  Appeal to fear of exaggerated consequences in the event an adversary’s argument prevails 8. Argument from Force (Argumentum ad baculum)  Substitutes veiled threats for logical persuasion or asserts something must be the case because “that’s just the way things are” 9. Argument from Ignorance (Argumentum ad ignoratiam)  Argues that a proposition is true simply on the basis that it has not been proved false, or that it is false because it has not been proved true  Exception: meeting one’s burden of proof in a trial  See:Sec. 2 Rules 133 Rules of Court (Proof beyond reasonable doubt)

10. Straw Man Argument  Includes any lame attempt to “prove” an argument by overstating, exaggerating, or over-simplifying the arguments of the opposing side 11. Fallacy of Stacking the Deck  The speaker “stacks the deck” in his favor by ignoring examples that disprove the point, and listing only those examples that support her case. This fallacy is closely related to hasty generalization, but the term usually implies deliberate deception rather than an accidental logical error.  Deception; using hearsay evidence 12. Hypothesis Contrary to Fact (Argumentum ad speculum)  Trying to prove something in the real world by using imaginary examples alone, or asserting that, if hypothetically X had occurred, Y would have been the result. 13. 

Genetic Fallacy Claims that an idea, product, or person must be untrustworthy because of its racial, geographic, or ethnic origin

B. Fallacies of Context and Content 1. Overzealous Application of a General Rule / Fallacy of Accident (Dicto simpliciter)  Applies a generalization to an individual case that it does not necessarily govern; the mistake often lies in failing to recognize that there may be exceptions to a general rule 2. Hasty Generalization / Fallacy of Selected Instances  Occurs when we construct a general rule from an inadequate number of incidents; results from enumerating instances without obtaining a representative number to establish an inductive generalization Fallacy of Statistical Simplicity  The probability of a sampling error tends to diminish as the size of the sample increases. But size alone is no protection. 3. False cause  Treats as the cause of a thing something that is not really its cause a. No causa pro causa o Mistakes what is not the cause of a given effect as the real cause; the

o

events could be so correlated because they were both caused by a third, unexamined event, although neither caused the other Event C happened immediately prior to Event E. Therefore, C caused E.

b. Post hoc ergo propter hoc o The suggested inference that one event is the cause of another simply because the first occurs earlier than the other; more prevalent in the law o B comes after A (post hoc). Therefore (ergo), B comes because of A (propter hoc). 4. Irrelevant Conclusion (Non sequitur) or Fallacy of the Consequent  Argument that contains a conclusion that does not necessarily follow from the premises or any antecedent statement offered in its support  The difference between the post hoc and the non sequitur fallacies is that the post hoc fallacy lacks a causal connection; the non sequitur fallacy lacks a logical connection.  E.g. when a sick person is treated by a witch doctor or a faith healer then becomes better, superstitious people conclude that the spell or prayer was effective 5. Compound (complex) questions  Arises when: (1) two or more questions are asked at once, and a single answer is required; (2) a question is phrased as to beg another question; (3) the question makes a false presumption or (4) the assertion frames a complex question but demands a simple answer.  See: Relevant rules on Evidence, e.g. laying the basis or predicate for questions in the examination of witnesses  E.g. Have you stopped beating your wife? 6.Circular Argument / Begging the question (Petition principii)  Assumes the truth of what one seeks to prove in the effort to prove it; the conclusion lies buried in the premises used to reached that conclusion  Case: Viray, et al. v. Court of Appeals, G.R. No. 92481, 9 November 1990 7. Tu quoque (appeal to hypocrisy)  A charge of wrongdoing is answered by a rationalization that others have sinned, or might have sinned.  Yet, in the law, tu quoque arguments can sometimes be used as an effective defense,

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e.g. in matters of provocation, in the equitable defense of in pari delicto See:Article 13(4), Revised Penal Code (mitigating circumstance of sufficient provocation or threat of the offended party which immediately preceded the act Case:Bercero v. Capitol Development Corporation, G.R. No. 154765, 29 March 2007 (in pari delicto; you should come to court in clean hands)

B. Linguistic Fallacies 1. Equivocation  Confuse several meanings of a word or phrase in the context of an argument; allow the meaning of a term to shift between the premises of the argument and the conclusion 2. Amphibology  Ambiguity comes from the grammatical structure; the double meaning lies not in the word but in the syntax or grammatical construction of a sentence  Arise in an argument where meaning is muddled by slovenly syntax – bad grammar, poor punctuation, dangling participles, misplaced modifiers 3. Composition

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Mistakenly impute the attributes of a part of a whole to the whole itself stereotyping

4. Division  Mistakenly argue that attributes of a whole must also be present in each part of that whole 5. Vicious Abstraction  Removal of a statement from its context, thereby changing the meaning of an argument 6. Argumentum ad nauseum  Unnecessarily long brief or a windbag oral argument where the advocate seeks to sustain his position by repetition piled upon repetition rather than by succinct, effective proof or logical development