Reference · Appendix B
This is the master list of every named wrong-answer pattern used in the book. The LSAT builds the same handful of traps over and over. Once you can name a trap, you can kill it on sight, which is the whole game (about 80 percent of all answer choices are wrong, so elimination is your primary skill).
How to use this appendix: when you keep falling for a particular kind of wrong answer, look it up here, reread the tell, then reread the chapter where it is taught in full. The patterns are grouped into LR traps and RC traps. Within each group they run roughly alphabetically by the short name we use in the chapters.
A note on overlap: some traps appear under both LR and RC because the test reuses them (too strong, out of scope, wrong-person attribution). The cross-references tell you where each is drilled hardest.
| Pattern | What it is (the tell) | Shows up in |
|---|---|---|
| Could-be-true (not must) | The answer is consistent with the stimulus and could be true, but the text does not force it to be true. On a “must be true” stem, possible is not enough: only what is locked down survives. Calibrate to the stem (a “most strongly supported” stem allows a small leap; “must be true” does not). | Must Be True / Inference (Ch. 8); Cannot Be True (Ch. 10, mirror) |
| Too strong / exaggerated | The answer overstates what the text supports: it turns some into all, a cause into the cause, evidence against into disproof, likely into certain. The idea is right but the force is too high. The most common single tell across the test. Everyday tell: when a friend insists they ‘never’ run late or that ‘everyone’ agrees with them, the absolute word (never, always, everyone) is usually the overstatement to flag, not the literal truth. | Must Be True (Ch. 8); Method/Role (Ch. 18); Main Conclusion (Ch. 9); appears everywhere |
| New information / out of scope | The answer introduces a term, group, or fact not present in the stimulus, and the stimulus does not license it. On Read-It types this is fatal (you cannot point to it). On Fix-or-Break-It types it is a softer red flag: new info is allowed there, but only if it actually connects to the link. | Must Be True (Ch. 8); Necessary Assumption (Ch. 11); Strengthen (Ch. 13); Weaken (Ch. 14) |
| Concept swap | The answer reuses a key term from the stimulus but quietly shifts its meaning, or swaps one of the argument’s concepts for a near-synonym that is not the same thing (likelihood for amount, popularity for quality). Looks like a match; is not. | Must Be True (Ch. 8); Necessary Assumption (Ch. 11); Flaw (Ch. 17) |
| Opposite answer | The answer does the exact reverse of the task: it weakens on a Strengthen stem, strengthens on a Weaken stem, deepens the puzzle on a Paradox stem. Tempting because it is clearly relevant. Always confirm the direction of your task before you pick. | Strengthen (Ch. 13); Weaken (Ch. 14); Resolve the Paradox (Ch. 16); Necessary Assumption (Ch. 11) |
| Reversed logic | For a conditional you need (A → B), the answer gives the reverse (B → A): a Mistaken Reversal dressed as the credited answer. Common where a bridge assumption is required. Check the arrow direction. | Necessary Assumption (Ch. 11); Sufficient Assumption (Ch. 12); Method/Role (Ch. 18) |
| Half-right / half-wrong | The answer starts accurate and finishes false (or vice versa). The correct opening sentence makes you commit before the wrong second clause lands. Read every word of the answer; one bad clause kills the whole choice. Everyday tell: directions that nail the first three turns then blow the last one are right at the start and wrong at the finish, which still leaves you lost. | Method/Role (Ch. 18); Parallel Reasoning (Ch. 19); Flaw (Ch. 17) |
| Premise booster | The answer supports or proves one of the argument’s premises. On Assumption and Strengthen stems this feels productive but is not the job: shoring up a premise the author already asserted does nothing for the premise-to-conclusion gap. | Necessary Assumption (Ch. 11); Strengthen (Ch. 13) |
| Conclusion restatement | The answer simply re-says the conclusion (sometimes in fresh words) instead of providing the assumption that links to it or the support that backs it. Restating the claim is not the same as supporting it. | Necessary Assumption (Ch. 11); Sufficient Assumption (Ch. 12); Strengthen (Ch. 13) |
| “Primary / most important factor” | An answer that calls something the primary, main, or most important cause or consideration. These are usually wrong: the argument almost never needs (or earns) a claim that one factor outranks all others. Treat the words “primary” and “most important” as a red flag. | Necessary Assumption (Ch. 11); Strengthen (Ch. 13) |
| Straw man | The answer attacks (or defends) a more extreme, more categorical version of the conclusion than the author actually drew. It weakens “X reduces harm” by refuting “X eliminates all harm.” Match the answer to the exact claim, not an inflated cousin. | Weaken (Ch. 14); Flaw (Ch. 17, as a named flaw) |
| Circular-reasoning bait | An answer choice that says the argument “assumes what it sets out to prove” or “begs the question.” Real circular reasoning occurs in under 5 percent of arguments, yet this phrasing is one of the most common wrong answers. Apply a strong presumption against picking it; only choose it if you can point to the conclusion literally reused as a premise. | Flaw (Ch. 17); Method/Role (Ch. 18) |
| Inapplicable flaw | The answer names a real, recognizable flaw type that the argument did not actually commit. Several genuine fallacies appear as choices; only one fits. Pinpoint where the error occurs in the stimulus before you match. | Flaw (Ch. 17); Method/Role (Ch. 18) |
| Describes-a-non-flaw | The answer describes a feature of the argument that is legitimate reasoning, then calls it an error (for example, “rejects a view because it was inadequately supported,” or “concedes a point and shows the conclusion still holds”). Normal moves are not flaws. Only pick a flaw you genuinely agree is faulty. | Flaw (Ch. 17) |
| Same-topic bait | On Parallel questions, an answer that matches the subject matter of the stimulus (both about economics, both about medicine) but not its logical structure. Topic is the decoy; you match form. Strip to a topic-free skeleton and ignore the content. | Parallel Reasoning / Flaw (Ch. 19) |
| Mismatched validity / force | On Parallel, an answer with the right general shape but a different validity (one argument is valid, the other is not) or a different conclusion force or quantity (must vs. probably, all vs. some, positive vs. negative). Match the conclusion’s certainty and quantity, and match valid-to-valid. | Parallel Reasoning / Flaw (Ch. 19) |
| Explains-only-one-side / deepens-the-paradox | On Paradox, an answer that accounts for only one of the two facts in tension, or one that makes the surprise worse rather than dissolving it (the deepens-the-paradox form is the Opposite trap for this type). The credited answer must let both stated facts be true and explain the surprise. | Resolve the Paradox (Ch. 16) |
| Affects-both-sides-equally | On Paradox, an answer that applies to both sides of the puzzle equally, so it cannot explain why they came out different. Also includes answers that introduce an irrelevant third category or draw a distinction within one side only. The right answer must hit the two sides differently. | Resolve the Paradox (Ch. 16) |
| No-variance | On Evaluate, an answer whose question, answered either way at its two extremes, leaves the conclusion unchanged. Run the Variance Test: plug in two opposite extreme answers; if the conclusion does not move in different directions, the choice is irrelevant and wrong. | Evaluate (Ch. 15) |
| Self-interest / ulterior-motive temptation | An answer that discredits a claim by pointing out the claimant has a motive or stands to benefit. Having a motive does not make a claim false; this is an ad hominem in disguise. Tempting on Flaw and Weaken; almost never the credited answer. Everyday tell: your neighbor clearly gains from selling you his old mower, but that motive alone does not prove the mower is junk. | Flaw (Ch. 17); Weaken (Ch. 14) |
| Pattern | What it is (the tell) | Shows up in |
|---|---|---|
| Too broad / outside scope | The answer covers more than the passage does: a new or related topic, a comparison the passage never makes, a generalization wider than the text supports. The most common Main Idea trap. Watch the word only, which often smuggles in an all-the-world claim. | Main Idea / Primary Purpose (Ch. 25); Detail / Inference (Ch. 25) |
| Too narrow (one paragraph) | The answer states the main point of a single paragraph as though it were the point of the whole passage. True but undersized. The credited Main Idea answer must cover the passage’s overall claim, not one stop along the way. | Main Idea / Primary Purpose (Ch. 25); Comparative two-passage Main Idea (Ch. 26) |
| Too strong (passages are cautious) | The answer is the right idea pushed past what the cautious, qualified academic prose actually says: “two shortcomings” becomes “no value,” “unlikely” becomes “impossible,” a measured view becomes a categorical one. RC passages hedge; match the hedge. | Detail / Inference (Ch. 25); Main Idea (Ch. 25); Tone (Ch. 25) |
| Contradicts the passage | The answer says the reverse of what the text says, often quoting the passage’s own vocabulary so it sounds grounded. Familiar words are not the same as a faithful claim. Go back and check the direction against the line. | Detail / Inference (Ch. 25) |
| Wrong-person attribution | The answer states a real view from the passage but assigns it to the wrong party. Passages routinely recount several parties’ positions (“behavioral economists hold X; classical economists hold Y; the author holds Z”); the trap hands you X but credits it to the author. Track who said what. | Detail / Inference (Ch. 25); Comparative passages (Ch. 26) |
| Second-meaning-of-a-word | On a word-in-context question, the answer gives a legitimate dictionary meaning of the cited word that is not the meaning it carries here. Read the line window (the sentence before, the line itself, and especially the sentence after) to fix the in-context sense. | Line / Function (Ch. 25) |
| Idea-from-elsewhere-in-the-passage | On a Line/Function question, the answer lifts a real idea from a different part of the passage than the one cited. Tempting to readers answering from memory rather than from the cited window. Retrieve from the exact lines named. | Line / Function (Ch. 25) |
| Wrong valence / wrong intensity | On Tone/Attitude, the answer has the wrong sign (positive vs. neutral vs. negative) or the right sign at the wrong strength (“unbridled enthusiasm” when the text is “qualified approval”). Valence is the fastest eliminator; intensity is judged by whether the text carries caveats and caution. | Tone / Attitude (Ch. 25) |
| The “other passage” trap | On a comparative set, an answer that is a perfect, accurate statement of the passage you are not being asked about. Expect roughly one of these on single-passage questions within a dual set. Confirm which passage the question targets before you pick. | Comparative passages (Ch. 26) |
| Only-in-one-passage | On a two-passage retrieval question (where the right answer must appear in both passages), an answer that is true of just one of them, often quoted to look appealing. Method: check Passage A first, eliminate anything not in A, then test survivors against B. | Comparative passages (Ch. 26) |
A few of these patterns are easy to confuse with each other. Keep the distinctions straight:
B → A for A → B). One is about the question’s direction; the other is about the arrow’s direction.For the full method behind catching each trap, see the chapter cited in its row. For matching stem language to a question type, see Appendix C, The Stem-to-Type Decoder. For the formal-logic moves behind reversed logic and conditional traps, see Appendix A.