PrepTest 113 · Section 3 · Question 23 (Parallel Reasoning)

Step 1 · Pre-Question Guidance · read this first

Question type

Parallel Reasoning

The one idea it tests

A rule exists to prevent a harm; the target does cause that harm, but using the rule against it would trigger a bigger harm elsewhere, so do not use it.

The basic logic

X-Ray the skeleton: purpose of a tool is to cut harm; the target really is harmful; using the tool would push things toward something worse; so do not use the tool here. The match needs the admission that the target is harmful and the backfire comparison.

Tiny words that decide it

“only reason”
“but”
“more”
“should not”

Playground logic

Mom's candy limit is meant to protect Tommy's teeth. Candy really is bad for teeth, but banning it at home would push Tommy to sneak candy at night without brushing, which is worse. So the burger ends: no ban.

Step 2 · The kid story

Tommy's Candy Defense

Mom was thinking about a total candy ban. Tommy, who hides candy in his sock drawer, gave a speech. 'The only reason for a candy rule would be to protect my teeth. And yes, candy is bad for teeth. I admit it. But if you ban candy at home, I will just eat it at night under my blanket, and I will not brush afterward because I will be hiding. That is way worse for my teeth than eating it after dinner and brushing.' Lulu wrote on her clipboard: 'Admits the harm. Shows the ban backfires.' Mom raised an eyebrow. 'You are admitting you would sneak candy?' Tommy froze. 'That was hypothetical,' he said. Mr. Whiskers knocked a lollipop off the dresser.

Step 3 · Try the model question

The only reason for a candy ban would be to protect Tommy's teeth. Candy does harm teeth. But if candy is banned at home, Tommy will eat it in secret without brushing, which harms teeth even more. So candy should not be banned at home.

Which one of the following reasons in a way most like Tommy's argument?

Step 4 · The courtroom tale

The Case of the Library Snack Ban

The library board proposed banning snacks to protect the books. Mr. Whitfield represented the readers. 'Your Honor, the only reason for this rule is to protect books from crumbs. Fine, snacks do make crumbs. But if snacks are banned, readers will sneak books to the cafe next door, where coffee spills are common. Coffee ruins books far worse than crumbs.' Judge Priscilla Vance tapped her gavel thoughtfully. 'So the rule would trade a small harm for a bigger one.' 'Precisely, Your Honor.' The judge declined to approve the ban. A librarian quietly hid a granola bar.

Step 5 · Work the real question

Open PrepTest 113, Section 3, Question 23 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

X-Ray the original into four parts: the rule's only purpose, the admission that the target is harmful, the backfire showing the rule leads to a worse version of that harm, and the 'do not do it' conclusion. Check each answer for all four with the ideas lined up alike. Cross off answers where the target is harmless, where there is no backfire, or where the conclusion favors the rule.