Flaws: Subjective/Objective Problem

Some flawed LSAT arguments infer a person’s intent from his or her actions (or vice versa).  If I were to accidentally knock a child down, I would not necessarily be guilty of child abuse.

This “subjective/objective” problem shows up periodically on the LSAT, but it is not otherwise common enough to be listed as a major fallacy. It only appears twice in 10 Actual Official LSAT Preptests, Volume VI (once as a correct answer and once as a wrong answer).

  • 72-2-5: Firepower movie (Vol VI, p. 16). 83% identified this as the correct answer to this “medium difficulty” question.
  • 74-4-18: Melatonin (Vol VI, p. 116). 7% chose this wrong answer to this “hardest difficulty” question.

Volume VI Flaws

The following work-in-progress is a hyperlinked list of the ANSWERS to flaw questions in “10 Actual Official LSAT Preptests Volume VI.” This document should immediately increase your accuracy on flaw questions by explaining what each answer means. If you carefully study the different flaws and the words the LSAT authors use to describe it, you should be able to get more right answers in less time in the LSAT logical reasoning section,

I recommend that this document be used as part of the 7Sage “blind review” method. Try to figure out each flaw question on your own, and then, without checking your  answer, look at that question in this document.  If you aren’t familiar with the labels I use  to describe the different flaws, just click the hyperlink to see what Wikipedia or other authors have said about this specific flaw. Then, after you are clear on what each answer actually means, choose your answer. If it is the same answer you originally chose, congratulations! If you changed your answer, congratulations again–you may have just learned something that will help you get into the law school of your choice!

72-2-5: Firepower movie (p. 17)

  1. Ad hominem
  2. Correlation does not imply causation
  3. Fallacy of composition
  4. Overlooked possibility
  5. Subjective/objective problem

72-2-14: Chocolate depression (p. 19)

  1. Reducing cause eliminates effect
  2. Unrepresentative sample
  3. Correlation does not imply causation
  4. Mistaken reversal
  5. Vague conclusion

72-2-16: Too many artworks (p. 20)

  1. Overlooked possibility
  2. Assumption
  3. Assumption
  4. Overlooked possibility
  5. Assumption

72-2-18: Blood samples (p. 20)

  1. Assumption
  2. Overlooked possibility
  3. Overlooked possibility
  4. Overlooked possibility
  5. Assumption

72-2-20: Wild apples (p. 21)

  1. Overlooked possibility
  2. Overlooked possibility
  3. Assumption
  4. Internal contradiction
  5. Circular reasoning

72-2-22: Flawed pattern (p. 22) is a mistaken reversal

72-3-7: Comics and health (p.26)

  1. Overlooked possibility
  2. Overlooked possibility
  3. Assumption
  4. Assumption
  5. Assumption

72-3-11: Hiking trail (p. 27)

  1. Argument from ignorance
  2. Fallacy of composition
  3. Circular reasoning
  4. Hasty generalization
  5. Ad hominem

72-3-14: Wildlife activists (p. 28)

  1. Mistaken negation
  2. Complete rejection of partial solution
  3. Overlooked possibility
  4. Ad hominem
  5. Rejection of one possible solution

72-3-22: Pathogenic microorganisms (p. 30)

  1. Overlooked possibility
  2. Overlooked possibility
  3. Overlooked possibility
  4. Overlooked possibility
  5. Overlooked possibility

72-3-25: Flawed pattern (p. 31) is a false dilemma

73-2-3: Movie rights to video games (p. 56)

  1. Hasty generalization
  2. Mistaken inference
  3. Circular reasoning
  4. Assumption
  5. Mistaken reversal

73-2-5: Primeval atom (p. 57)

  1. Appeal to authority
  2. Equivocation
  3. Correlation does not imply causation
  4. Evidence may support more than one hypothesis
  5. False dilemma

73-2-7: Flawed pattern (p. 58) is ad hominem

73-2-13: Crime rate (p. 59)

  1. Assumption
  2. Overlooked possibility
  3. Overlooked possibility
  4. Assumption
  5. Assumption

73-2-15: Advertising campaign (p. 60)

  1. Assumption
  2. Overlooked possibility
  3. Assumption
  4. Assumption
  5. Mistaken reversal

73-2-18: Planimetric art (p.61)

  1. Ad hominem
  2. Equivocation
  3. Mistaken reversal
  4. Internal contradiction
  5. Argument from ignorance

73-4-3: Sunscreen lotions (p. 73)

  1. Assumption
  2. Overlooked distinction
  3. Overlooked possibility
  4. Statistical error
  5. Overlooked possibility

73-4-10: Vacuum cleaner (p. 74)

  1. Overlooked possibility
  2. Assumption
  3. Assumption
  4. Overlooked possibility
  5. Overlooked possibility

73-4-18: Flawed pattern (p. 77) is the gambler’s fallacy

73-4-25: Roberta is irritable  (p. 79)

  1. Correlation does not imply causation
  2. Circular reasoning
  3. Hasty generalization
  4. Mistaken reversal
  5. Mistaken reversal

74-1-5: Children’s television (p. 89)

  1. Mistaken reversal
  2. Argument from ignorance
  3. Ad hominem
  4. Appeal to authority
  5. Internal contradiction

74-1-16: Pedagogical practice (p. 92)

  1. Concedes opponent’s assumption
  2. Assumption
  3. Overlooked possibility
  4. Equivocation
  5. Assumption

74-1-18: Sleep deprivation (p. 93)

  1. Alternate cause
  2. Alternate cause
  3. Mistaken reversal
  4. Assumption
  5. Overlooked possibility

74-1-25: Flawed pattern (p. 95) is mistaken reversal

74-4-8: Kodiak bear (p. 114)

  1. Hasty generalization
  2. Overlooked possibility
  3. Equivocation
  4. False dilemma / Assumption
  5. Appeal to authority

74-4-15: Interest rates (p. 115)

  1. Relies on experts
  2. Confuses terms
  3. Assumption
  4. Mistaken negation
  5. Unwarranted inference

74-4-18: Melatonin (p. 116)

  1. Subjective/objective problem
  2. Bias
  3. Equivocation
  4. Reverse cause
  5. Unrepresentative sample

74-4-20: Global recessions (p. 117)

  1. Circular reasoning
  2. Fails to establish claim
  3. Circular reasoning
  4. Overlooked possibility
  5. Possibility v. Certainty

74-4-22: Fish with teeth (p. 117)

  1. Correlation does not imply causation
  2. Argument from ignorance
  3. Mistaken negation
  4. Possibility v. Certainty
  5. Appeal to authority

74-4-25: Flawed pattern (p. 119) is a mistaken most

75-1-7: Sherwood opposes higher taxes (p. 130)

  1. Unrepresentative sample
  2. Overlooked possibility
  3. Mistaken negation
  4. Ad hominem
  5. Fallacy of division

75-1-12: Duke of Acredia (p. 131)

  1. Overlooked possibility
  2. Contrapositive (not a flaw)
  3. Unreliable evidence
  4. Correlation does not imply causation
  5. Assumption

75-1-18: Police graft (p. 132)

  1. Hasty generalization
  2. Overlooked possibility
  3. Appeal to character
  4. Assumption
  5. Internal contradiction

75-1-22: Flawed pattern (p. 134) is mistaken most

75-3-7: Profit projections (p. 145)

  1. Assumption
  2. Overlooked distinction
  3. Overlooked possibility
  4. Hasty generalization
  5. Equivocation

75-3-10: Television host (p. 146)

  1. Argument from ignorance
  2. Circular reasoning
  3. Appeal to authority
  4. Confuses standards
  5. Questions conclusion merely because it was reached quickly

75-3-14: Flawed pattern (p. 147) is unique

75-3-16: Planned locomotion (p. 148)

  1. Mistaken reversal
  2. Assumption
  3. Assumption
  4. Assumption
  5. Assumption

74-3-18: Consumer advocate (p. 149)

  1. Mistaken reversal
  2. Overlooked possibility
  3. Unrepresentative sample
  4. Assumption
  5. Assumption

76-2-1: Reptile hormones (p. 176)

  1. Provides no explanation for other abnormalities
  2. Overlooked possibility (resolves the mistaken reversal in the stimulus)
  3. Overlooked possibility
  4. Overlooked possibility
  5. Unrepresentative sample

76-2-4: Chameleon behavior (p. 177)

  1. Hasty generalization
  2. Fails to explain
  3. Appeal to authority
  4. Fails to demonstrate
  5. Holds critics to a higher standard

76-2-16: Legislature survey (p. 180)

  1. Is/ought problem
  2. Circular reasoning
  3. Fallacy of composition
  4. Survey error
  5. Rough estimates yield precise conclusion

76-2-19: Union leaders (p. 181)

  1. Genetic fallacy
  2. Assumption
  3. Genetic fallacy
  4. Assumption
  5. Assumption

76-2-21: Flawed pattern (p. 182) is multiple causes

76-4-5: Traditional rituals (p. 193)

  1. Assumption
  2. Assumption
  3. Assumption
  4. Assumption
  5. Assumption

76-4-6: Flawed pattern (p. 193) is affirming a disjunct

76-4-13: Government statistics (p. 195)

  1. Equivocation
  2. Overlooked possibility
  3. Overlooked possibility
  4. Overlooked possibility
  5. Assumption

76-4-15: Nutritional supplements (p. 195)

  1. Equivocation
  2. Appeal to authority
  3. Appeal to emotion
  4. Ad hominem
  5. Assumption

77-2-5: Flawed pattern (p. 217) is unique.

77-2-14: Cancer and pollutants (p. 220)

  1. Overlooked possibility
  2. Overlooked possibility
  3. Assumption
  4. Overlooked possibility
  5. Overlooked possibility

77-2-18: Shakespeare snobs (p. 221)

  1. Assumption/Ad hominem
  2. Assumption
  3. Overlooked possibility
  4. Overlooked possibility
  5. Circular reasoning

77-2-22: More than one newspaper (p. 222)

  1. Confuses inabilities
  2. Overlooked possibility
  3. Is/ought problem
  4. Assumption
  5. Concerned only with important stories

77-4-6: Popular sports (p. 233)

  1. Correlation does not imply causation
  2. Hasty generalization
  3. Equivocation
  4. Circular reasoning
  5. Ad hominem

77-4-9: Joshi campaign (p. 234)

  1. Correlation does not imply causation
  2. Mistaken reversal
  3. Is/ought problem
  4. Reverse causation
  5. Circular reasoning

77-4-12: Movie critics (p.235)

  1. Argument from ignorance
  2. Overlooked possibility
  3. Unrepresentative sample
  4. Ad hominem
  5. Overlooked possibility

77-4-15: Flawed pattern (p. 239) is hasty generalization

78-1-7: Air traffic (p. 249)

  1. Hasty generalization
  2. Overlooked possibility
  3. Overlooked possibility
  4. Argument from ignorance
  5. Overlooked possibility

78-1-9: Prairie plants (p. 250)

  1. Reverse causation
  2. Fails to describe mechanism
  3. Assumption
  4. Unrepresentative sample
  5. Numbers v. Percents

78-1-21: Flawed pattern (p. 254) is “‘or’ does not equal ‘and’.” (This is an especially difficult question because the phrase “sand or organic material, or both” sounds so plausible. If you replace “organic material” with “pixie dust,” however, the flaw becomes apparent.)

78-1-22: Toxic chemicals (p. 254)

  1. Internal contradiction
  2. Overlooked possibility
  3. Argument from ignorance
  4. Reverse causation
  5. Overlooked possibility

78-3-1: Nonprofit  organization (p. 264)

  1. Unrepresentative sample
  2. Assumption
  3. Survey error
  4. Relies on majority opinion to determine minority opinion
  5. Assumption

78-3-5: Site drainage (p. 265)

  1. Overlooked possibility
  2. Overlooked possibility
  3. Overlooked possibility
  4. Overlooked possibility
  5. Overlooked possibility

78-3-15: Good manager (p. 267)

  1. Confuses qualities
  2. Confuses qualities
  3. Mistaken reversal
  4. Overlooked possibility
  5. Assumption

78-3-25: Flawed pattern (p. 271) is mistaken most.

79-1-2: Trusting neighbors (p. 288)

  1. Mistaken negation
  2. Is/ought problem
  3. Internal contradiction
  4. Circular reasoning
  5. Reverse causation

79-1-6: Body size (p. 289)

  1. Alternate causation
  2. Unrepresentative sample
  3. Alternate causation
  4. Fallacy of division
  5. Hasty generalization

79-1-13: Zoo animals (p. 291)

  1. Assumption
  2. Hasty generalization
  3. Straw man
  4. Mistaken reversal
  5. Rejects a claim because its proponent holds an inconsistent view

79-1-15: Success and luck (p. 291)

  1. Mistaken reversal
  2. Appeal to authority
  3. Circular reasoning
  4. Reverse causation
  5. Ad hominem

79-1-26: Flawed pattern (p. 295) is “some dogs are pets but no cats are dogs so no cats are pets.”

79-4-9: Fitness experts (p. 314)

  1. Correlation does not imply causation
  2. Assumption
  3. Infers that a factor that is a contributor is the only contributor
  4. Hasty generalization
  5. Fallacy of division

79-4-16: Flawed pattern (p. 316) is mistaken reversal

79-4-18: High school graduates (p. 316)

  1. Fails to establish
  2. Overlooked possibility
  3. Assumption
  4. Assumption
  5. Assumption

80-1-2: Hair dryers (p. 328)

  1. Numbers v. Percents
  2. Does not provide specific information
  3. Fails to discuss sales figures
  4. Overlooked possibility
  5. Provides no independent evidence

80-1-13: Purpose of laws (p. 331)

  1. Mistaken negation
  2. Correlation does not imply causation
  3. Equivocation
  4. Is/ought problem
  5. Fallacy of division

80-1-16: Commercial flights (p.332)

  1. Assumption
  2. Overlooked possibility
  3. Ad hominem
  4. Assumption
  5. Argument from ignorance

80-1-24: Flawed pattern (p. 335) is mistaken most

80-4-1: Community cleanup (p. 352)

  1. Hasty generalization
  2. Assumption
  3. Mistaken reversal
  4. Overlooked possibility
  5. No true Scotsman

80-4-11: University food vendor (p. 355)

  1. Overlooked possibility
  2. Unrepresentative sample
  3. Overlooked possibility
  4. Overlooked possibility
  5. Argues that a popular position ought to be adopted

80-4-16: Software company logo (p. 356)

  1. Correlation does not imply causation
  2. Mistaken negation
  3. Fallacy of division
  4. Circular reasoning
  5. Hasty generalization

80-4-23: Flawed pattern (p. 358) is roll the dice

80-4-26: Macedonian tombs (p. 359)

  1. Assumption
  2. Assumption
  3. Does not show
  4. Fails to evaluate
  5. Assumption

81-2-8: Employee bonuses (p. 377)

  1. Overlooked possibility
  2. Overlooked possibility
  3. Fails to justify
  4. Fallacy of division
  5. Assumption

81-2-20: Voting records (p. 381)

  1. Faulty comparison
  2. Fails to take into account
  3. Provides evidence but not explanation
  4. Reverse causation
  5. Overlooked possibility

81-2-24: Flawed pattern (p. 383) is argument from ignorance

81-2-25: Technological innovations (p. 383)

  1. Circular reasoning
  2. Argument from ignorance
  3. Stronger evidence than conclusion requires
  4. Mistaken reversal
  5. Hasty generalization

81-3-7: Economic productivity (p. 386)

  1. Assumption
  2. Assumption
  3. Unfairly criticizes politicians in general
  4. Assumption
  5. Fails to address

81-3-9: Brain area (p. 386)

  1. Assumption
  2. Overlooked possibility
  3. Hasty generalization
  4. Overlooked possibility
  5. Assumption

81-3-13: Legislator investment (p. 388)

  1. Treats a character trait as evidence of a viewpoint
  2. Fails to address the argument
  3. Assumption
  4. Assumption
  5. Overlooked possibility

81-3-15: Car manufacturers (p. 388)

  1. Hasty generalization
  2. Assumption
  3. Overlooked possibility
  4. Assumption
  5. Equivocation

81-3-23: Negotiated legislation (p. 391)

  1. Circular reasoning
  2. Mistaken negation
  3. Equivocation
  4. Assumption
  5. Bases conclusion on a different principle

Formal and Informal Fallacies

“Flaw” questions involve one of three types of errors–faulty assumptions, logical errors (technically known as “formal fallacies”), and other types of faulty reasoning (the “informal fallacies”). Unscrupulous people have exploited these fallacies for so many centuries that most of them have their own Latin names and all of them have their own Wikepedia page. The following is a list of fallacies that have appeared on LSAT preptests, in alphabetical order by Wikipedia entry.

Formal Fallacies

Most logicians use the term “antecedent” for the first term in a conditional statement and “consequent” for the last term. The LSAT never uses these terms, however. All LSAT materials call the “antecedent” the “sufficient term” and the “consequent” the “necessary term.”

Informal Fallacies
  • False dilemma
  • May/Must fallacy (surprisingly, Wikipedia has no entry for this)

Logical Error Flashcards

[qwiz] [i]

Logical errors (more precisely known as “formal fallacies”) involve errors that can be reduced to symbolic logic, regardless of the actual content of the argument.  This quiz identifies all the formal fallacies found in 10 Actual Official LSAT Preptests Volume V, using Wikipedia’s name for each error.

PowerScore has trademarked their names for these errors, so the first few entries take PowerScore’s definitions and match them to the Wikipedia names.

[q multiple_choice=”true”] Take a conditional statement (A->B) and then negate both terms (/A=>/B). This logical error is known as:

[c] A trademarked PowerScore error

[f] Well, yes, but that doesn’t help us much here, does it? You can find what PowerScore calls this in Chapter 6 of the Logical Reasoning Bible.

[c] Denying the Consequent

[f] No, that one isn’t a fallacy. If the “consequent” (which the LSAT refers to as the “necessary term” is false, the “antecedent” (a/k/a the “sufficient term”) must also be false.

[c*] Denying the Antecedent

[f] Good! The “antecedent” is the first term in a conditional, which the LSAT routinely refers to as the “sufficient” term.

[q multiple_choice=”true”] Take a conditional statement (A->B), assume the second term is true, and conclude that the first term must be true as well.

[c] A trademarked PowerScore error

[f] Well, yes, but that doesn’t help us much here, does it? You can find what PowerScore calls this in Chapter 6 of the Logical Reasoning Bible.

[c*] Affirming the Consequent

[f] Good! The “consequent” is the second term in a conditional, which the LSAT routinely refers to as the “necessary” term.

[c] Denying the Consequent

[f] No, that one isn’t a fallacy. If the “consequent” (which the LSAT refers to as the “necessary term” is false, the “antecedent” (a/k/a the “sufficient term”) must also be false.

[q multiple_choice=”true”] Only people in group A were cured. Therefore if anyone wasn’t cured, he must not have been in group A.

[c*]  Denying the Antecedent

[f] Correct! You can’t get from C->A to /C->/A. That would be like going from “If I live in California then I live in America” to “If I don’t live in California I don’t live in America.”

[c] Appeal to probability

[f] No, that would mean mistaking a condition that MIGHT happen for  a condition that MUST happen.

[/qwiz]

 

Flaw Questions

“Flaw” type questions come in three basic forms–assumptions, logical errors, and fallacies. Doing well on flaw questions means doing well on each of these three very different challenges.

Assumptions

Assumptions are easiest for people with no special training in logic. It is easy to spot an assumption type answer, since  it tends to start with a phrase like “fails to consider that” or “takes for granted that.” In a typical assumption scenario, the answer choice will provide a new fact that would make a big difference to the argument. You don’t need to be a logic whiz to figure out how that new fact might change things. Since each assumption-type answer is unique to the facts in that particular argument, there is no easy way to train up to do better on assumption answers.

Logical Errors

Logical errors, by contrast, do not involve new facts. They are technically known as “formal fallacies,” which means they are wrong because of the “form” of the argument. Any “formal fallacy” can be reduced to symbolic logic so that the actual terms under discussion no longer matter. A stimulus that says “Albion is in Britain” can be rewritten as “A->B.” In a “formal fallacy,” it doesn’t matter whether “B” stands for “Britain” or “Botswana.” For example, if I say “I am in Britain, therefore I am in Albion,” I have committed the logical error that PowerScore refers to as a “mistaken reversal.” To do well on this type of flaw question, you need to do well on conditional logic as a whole. I am working on a flashcard deck for logical errors.

  • Logical error flashcards
Fallacies

The third type of flaw is a specialized version of logical errors that cannot be reduced to symbolic logic. These “informal fallacies” involve a host of tricks and traps for the unwary. Unscrupulous people have been using these fallacies to dupe people for so many centuries that most of them have Latin names. These Latin names never appear on the LSAT, which adds an unintended degree of difficulty to the test. The LSAT answer choices that describe these informal fallacies can be more bewildering than Latin, especially to people who have some familiarity with the traditional names. To address this problem, I am working on two sets of informal fallacy flash cards–one that identifies all the most common and/or recent fallacies by their Wikipedia names, and another which then connects those names to wording that mimics the LSAT answer choices.

  • List of fallacies
  • Fallacy flashcards
  • Flaw answer choices

Informal Fallacy Flashcards

[qwiz] [i]

Informal Fallacies: This quiz identifies all the informal fallacies in 10 Actual Official LSAT Preptests Volume V. Since many fallacies have more than one name, we have chosen the name used by Wikipedia for each fallacy.

[q multiple_choice=”true”] presents a situation in which only limited alternatives are considered, when in fact there is at least one additional option.

[c]  Sampling bias

[f] No, that would involve some kind of survey error.

[c] Begging the question

[f] No, that would mean assuming what you are trying to prove.

[c*] False dilemma

[f] Good! 

[q multiple_choice=”true”]  infers that something is true of the whole from the fact that it is true of some (or even every) part of the whole

[c*] Fallacy of Composition

[f] Good!

[c] Argument from ignorance

[f] No, that would mean using a lack of proof as a way of proving something.

[c] May/Must Fallacy

[f] Wikipedia doesn’t know about this one–it is the error of saying something must be true just because it might be true.

[/qwiz]

 

 

The “Roll the Dice” Flaw

“Find the flaw” LSAT questions are both common and difficult. There are a lot of fallacies, and some of them are quite subtle.  The answer choices use “LSAT jargon” to describe each fallacy, not textbook Latin. That means you have to know the fallacy and the special LSAT terminology for it to answer the question with speed and confidence.

I recently ran across a “find the flaw” question that totally stumped me. I guessed one answer (with no confidence) on a timed test, then came back to blind review and picked another answer–still without any certainty. Both my choices turned out to be wrong, so I looked up the answer and promised to write a blog post about it. (I recommend this same procedure to students who want a 99th percentile score–you haven’t really mastered a question until you either know you got it right  or you write an essay about why you got it wrong.)

The question I had trouble with was PrepTest 65, Secton 4, #26. I won’t violate copyright by printing it here, so here’s a new problem with the same features. (If you own “10 Actual, Official LSAT PrepTests Volume V” you can find the actual question on page 143.

Nikola Tesla Magnet School accepts only the brightest students in our metropolitan region, so it boasts the best science club in the entire Tri-State Area. The best science club is most likely to win the annual robotics competition, so the Nikola Tesla Magnet School will almost certainly bring home the trophy this year.

I read this stimulus and immediately zeroed in on the difference between the best individual students and the best overall team. That’s such a common fallacy that it has a Latin name (“modo hoc“), although it’s not clear whether it applies in this case. But I never got that far because that wasn’t one of my answer choices. Here’s what was offered on the LSAT:

(A) presumes, without presenting relevant evidence, that an entity can be distinguished as the best only on the basis of competition.

(B) predicts the success of an entity on the basis of features that are not relevant to the quality of that entity.

(C) predicts the outcome of a competition merely on the basis of a comparison between the parties in that competition.

(D) presumes, without providing warrant, that if an entity is the best among its competitors, then each individual part of that entity must also be the best.

(E) concludes that because an event is the most likely of a set of possible events, that event is more likely to occur than not.

I was trying so hard to find a composition fallacy (that’s modo hoc for you Latin lovers) that I really wanted D to be correct, but it just wouldn’t work. I wound up picking C, then switched to A. B never appealed to me, and I never really understood what E was all about.

That was a mistake.

E is all about rolling dice. If I roll a pair of dice, seven is the most likely outcome. There are six out of thirty-six chances that I will roll a seven, making it more likely than any other roll (there’s a 1/36 chance of rolling two or twelve, a 2/36 chance of rolling three or eleven, etc., etc.). But just because seven is the single most likely roll, it’s not more likely to occur than not. I only roll a seven one out of six times. I’d have to roll it every other time (plus some) for it to be “more likely to occur than not.”

Most likely, but not more likely than not

That was my error. A science club may be “more likely” to win than any other club in the city, but that doesn’t mean it will “probably” win.

I’ve searched the Internet for the Latin name of this fallacy, and haven’t found it yet. You Latin buffs may refer to it as “alea jacta est.” The rest of us can just call it the “roll of the dice fallacy.”

Find the Flaw: A Difficult But Useful Skill

Some things you do to prepare for the LSAT are a waste of time as far as the rest of your life in concerned. Your ability to recognize a “parallel reasoning” question and skip over it until the end of the section is not going to help you be a better lawyer. But that is not true of all LSAT preparation. At least one area where you need to invest some significant time will serve you well throughout your life and legal career. That area is the “find the flaw” logical reasoning question type.

Logicians call these “flaws” fallacies, and diagnose them as carefully as doctors do diseases. If you take an old-fashioned logic class in an academic setting, you may still be expected to learn their Latin names, such as argumentum ad hominem, argumentum ad baculum, argumentum ad misericordiam, etc.

It used to be you couldn’t be a lawyer without knowing quite a bit of Latin, but aspiring lawyers aren’t expected to learn Latin anymore. That’s why the LSAT doesn’t give you Latin names in the answer choices. Unfortunately, the answer choices they do provide might as well be in Latin for all the good they do the brand-new test-taker. “Find the flaw” answer choices are worded in what I call “LSAT jargon,” a unique dialect found nowhere else on earth.

It isn’t that “find the flaw” answer choices aren’t in English, or that they don’t actually mean something. The problem is that an intelligent person can read the answer twelve times in a row and still not get what the test-writer is saying. Sometimes the only way to figure out what these answer choices mean is to look at the answer in the back of the book. Only after you see that “E” is the right answer will the fog clear and understanding set in. But by that time, you’ve already circled “C,” changed it to “A,” and beaten your head against a wall.

That’s the bad news. The good news is that LSAT jargon is no harder to learn than Latin, and the effort you make on this one question type will serve you the rest of your life. You will need to spot flawed reasoning in every contract you review, will you draft, deposition you take, or witness you put on the stand. On the LSAT, you have more than a minute to figure out a “find the flaw” problem. When your opponent is making her pitch to the jury, you have scant seconds; and when you explain your objection to the judge, you need to speak English, not Latin.

You might impress a jury by saying, “Your Honor, the counsel for the prosecution has committed a post hoc, ergo propter hoc fallacy,” but if the judge got his law degree in the last twenty years, you’re more likely to annoy him than persuade him. Try saying, “The State has confused a cause with a correlation, your Honor. Just because one thing happens after another thing does not mean it was caused by that other thing.” That might get your objection sustained and your client out of jail! And when your grateful client hugs you and hands you a check, you can say, “Don’t thank me–thank the LSAT!”