Logical Reasoning · Method of Argument

PrepTest 104 · Section 4 · Question 21

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

Step 1 · Pre-Question Guidance · read this first

Question type

Method of Argument

The one idea it tests

One way to defeat a counterexample is to shrink the rule until the counterexample falls outside it.

The basic logic

The argument states a rough generalization, admits a case that seems to break it, then offers a tighter version that only covers a certain kind of case. The troublesome case is not that kind, so it no longer counts against the rule. Describe the move, not the content: the rule got narrower.

Tiny words that decide it

“seems”
“however”
“if”
“resolves”

Playground logic

Ms. Rivera's rule says gold stars go to helpers. Kevin got one for reading alone, which seems to break it. So Ms. Rivera narrows the rule to only two-kid activities, and Kevin's solo reading drops out of the picture.

Step 2 · The kid story

The Gold Star Puzzle

Lulu studied the sticker chart. "Every gold star goes to a kid who helped somebody. Nadia helped Owen with fractions. Tommy helped Kevin carry the fish tank. Gold stars." Then she squinted. "But Kevin has a gold star for reading a whole chapter book by himself. He helped nobody. My rule is broken!" Ms. Rivera smiled. "Try this rule instead. When a star is for something two kids do together, like buddy reading or carrying things, the star goes to the one doing the helping." Lulu thought. "Kevin read alone. That is not a two-kid thing." "Exactly," said Ms. Rivera. "So Kevin's star is not about my new rule at all." Lulu crossed out her old rule and wrote the smaller one. "Smaller, but it still works."

Step 3 · Try the model question

Most gold stars seem to go to kids who helped someone. Kevin's star for reading alone seems to be a counterexample. But the puzzle is solved by this rule: when a star is for a two-kid activity, it goes to the kid who did the helping.

How does the argument handle the apparent counterexample?

Step 4 · The courtroom tale

The Shrinking Rule

Counselor Brisk argued for the parking company. "Every ticket in this lot goes to the driver who parked badly. Yet here is Mr. Tuttle, ticketed while his car sat perfectly in the lines!" Mr. Whitfield stood, adjusting his suspenders. "Your Honor, the company's rule is a bit too big. Let me trim it. When a ticket involves two cars in a dispute, it goes to the car that blocked the other." The judge leaned forward. "And Mr. Tuttle's ticket?" "Was for an expired meter. No second car at all," said Mr. Whitfield. "So his ticket is simply outside the trimmed rule." The judge nodded. "The counterexample no longer matters. Proceed."

Step 5 · Work the real question

Open PrepTest 104, Section 4, Question 21 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Map three pieces: the rough rule, the case that seems to break it, and the fix. Ask what the fix does to the rule. Does it add support, dismiss the case, admit an exception, or limit which cases the rule covers? Match that move in abstract terms. Reject answers describing steps the argument never takes, and answers that claim the counterexample was shown to be fake rather than set aside.