Logical Reasoning · Role of a Statement

PrepTest 154 · Section 2 · Question 18

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

Step 1 · Pre-Question Guidance · read this first

Question type

Role of a Statement

The one idea it tests

A premise can hold up a conclusion that is itself an if-then claim, not a flat fact.

The basic logic

Find the top bun first. Notice whether it says 'if X, then Y' instead of just 'Y'. Then check whether the target statement is a reason ('because') feeding that if-then Boss.

Tiny words that decide it

“if”
“then”
“because”
“by definition”

Playground logic

Marcus builds a burger whose top bun is an if-then: IF a sticker set is just its exact list of stickers, THEN any trade changes the set. The patty is his 'because': under that idea, losing one sticker makes a new set. That patty is a Helper working for a conditional Boss.

Step 2 · The kid story

Kevin's Sticker Set Crisis

Kevin owns a binder of dinosaur stickers and calls it 'The Set.' Frankie and Sharon argue at lunch about whether trading stickers ever changes The Set. Marcus pushes up his detective glasses. "Some people say a set is nothing more than the exact list of stickers inside it," he says. "If that idea is right, then every trade Kevin makes changes The Set, even if it's a tiny change. Why? Because under that idea, taking out any single sticker would make it a different set, by definition." Kevin gasps and hugs his binder. Lulu writes on her clipboard: 'Marcus did not say the idea IS right. He only said what follows IF it is.' Priya sips her juice box. "That last 'because' part is his reason," she says. "It props up the if-then."

Step 3 · Try the model question

Marcus: Some people say a sticker set is just the exact list of stickers in it. If that is correct, then every trade changes the set, because under that idea, removing any sticker would by definition make it a different set.

The claim that, under that idea, removing any sticker would make it a different set serves in Marcus's argument as which one of the following?

Step 4 · The courtroom tale

The Case of the Shrinking Choir

Mr. Whitfield snaps his suspenders. "Your Honor, the club rules say the choir is simply the list of its singers. My client does not claim that rule is wise. I claim only this: if the rule is the true meaning, then every singer who quits changes the choir. Why? Because under that rule, losing any single voice makes it a different group by definition." Judge Pemberton nods slowly. "So your 'because' is the support, and your big claim is an if-then." "Exactly," says Mr. Whitfield. "I am not saying the choir is gone. I am saying what follows if the rule holds." The judge scribbles: Helper statement, conditional Boss.

Step 5 · Work the real question

Open PrepTest 154, Section 2, Question 18 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Find the top bun and check its shape: is it a flat claim or an if-then? Next, locate the target statement and ask what job it does. Look for a 'because' or similar signal linking it to the conclusion. If it supplies the reason the if-then holds, it is a Helper for a conditional Boss. Pick the choice that names that job, and reject choices that call it the conclusion, a definition alone, or something the argument rejects.