Logical Reasoning · Flaw

PrepTest 142 · Section 2 · Question 1

Phase 1 (your first ~400 questions): read the guidance, then answer. No clock.

Step 1 · Pre-Question Guidance · read this first

Question type

Flaw

The one idea it tests

A word that carries two meanings can make two claims look like they clash when they do not.

The basic logic

The speaker says the other person contradicts himself. Check whether one key word is used in one sense in the first claim and in a different sense in the second. If so, there is no clash at all.

Tiny words that decide it

“right”
“absurd”
“but also”

Playground logic

Kevin thinks Lulu contradicted herself about his sticker book. But Lulu used the word "allowed" in two ways: once for what the house rules permit, once for what is kind. Kevin's top bun ("you make no sense") only works if the word means the same thing both times. That is a Slippery Word.

Step 2 · The kid story

Kevin and the Sticker Book

Kevin got a dinosaur sticker book from Grandpa. "It's mine," he announced, "so I'm allowed to rip out any page I like." Lulu checked her clipboard. "Yes. Grandpa said it's yours. You're allowed by the rules." Kevin grinned. Then Lulu added, "But Tommy helped you finish that T. rex page all weekend. If you rip it out, he'll be sad. So you're not allowed to rip that page." Kevin threw up his hands. "First you say I'm allowed, then you say I'm not! You make zero sense!" Priya sipped her juice box. "She makes plenty of sense, Kevin. The first 'allowed' was about the rules. The second 'allowed' was about being nice. You can be allowed by the rules and still not be allowed by kindness." Kevin thought about it, then put the T. rex page back.

Step 3 · Try the model question

Kevin to Lulu: You agree that, by the rules, the sticker book is mine and I may rip out any page. Yet you also say that since Tommy will be sad, I may not rip out the T. rex page. Plainly, you are saying two things that cannot both be true.

Which one of the following best describes a weakness in Kevin's reasoning?

Step 4 · The courtroom tale

The Case of the Two Kinds of Free

Mr. Whitfield snapped his suspenders. "Your Honor, the witness says the bakery is free to paint its sign purple. Then she says the bakery is not free to do it, because the neighbors will hate it. She contradicts herself!" The judge peered over her glasses. "Counselor, 'free' in the first sentence means the town code allows it. 'Not free' in the second means good neighbors would not do it. Those are separate sorts of free." Mr. Whitfield blinked. "So she can say both?" "She can," said the judge. "Your argument slipped on a word. Objection overruled." The witness smiled and smoothed her sweater.

Step 5 · Work the real question

Open PrepTest 142, Section 2, Question 1 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Read the speaker's charge: the other person has said two things that supposedly cannot both be true. Find the key word that shows up in both claims. Ask: does it mean the same thing each time? Try one meaning for the first claim and another for the second. If both claims can then be true together, the flaw is a Slippery Word. Pick the answer that names the shift in meaning, not one about evidence, timing, or attacking the person.