Logical Reasoning · Principle (Justify)

PrepTest 116 · Section 4 · Question 2

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

Step 1 · Pre-Question Guidance · read this first

Question type

Principle (Justify)

The one idea it tests

Find the rule that bridges the gap between what the premises are about and the new action the conclusion talks about.

The basic logic

The premises show doing X is wrong. The conclusion says something next door to X (saying or planning X) is wrong. The principle you want connects the two: if doing it is wrong, then that neighbor action is wrong too.

Tiny words that decide it

“immoral”
“since”
“even when”
“also”

Playground logic

Lulu proves that taking a classmate's snack breaks the rule (patty), then jumps to planning it breaks the rule too (top bun). The secret sauce is a bridge: whatever is against the rules to do is against the rules to plan.

Step 2 · The kid story

Lulu's Snack Law

At lunch, Lulu taps her clipboard. "Rule one: it's against the rules to take anything that belongs to another kid." Tommy is staring at Owen's pudding cup. "Grabbing Owen's pudding would take his stuff," Lulu goes on. "So it's also against the rules to even plan to grab it. Even if you only plan it to get back at him for eating your crackers." Tommy groans. "I didn't DO anything!" Priya leans in. "Lulu, your rule talks about doing. Your conclusion talks about planning. You need one more line on that clipboard." Lulu writes it in purple marker: "If something is against the rules to do, it's against the rules to plan." Now the argument clicks shut. Tommy sighs and eats his apple.

Step 3 · Try the model question

Lulu: It is against the rules to take anything that belongs to another kid. Grabbing Owen's pudding would take something of his. So it is also against the rules to plan to grab it, even as payback.

Which rule, if accepted, does the most to back up Lulu's reasoning?

Step 4 · The courtroom tale

The Case of the Drawn Map

A town rule forbade climbing the old water tower. Young Felix was hauled in for drawing a map of how to climb it. Prosecutor Grimsby argued: "Climbing is forbidden. Felix's map shows a climb. So drawing the map is forbidden too." Judge Okafor tapped her pen. "Your rule speaks of climbing, counselor. Felix only drew." Mr. Whitfield rose. "Your Honor, the prosecutor needs another rule, something like: whatever is forbidden to do is forbidden to plan. That law is not on the books." Grimsby flipped pages for a long time. "Then my argument has a hole," he admitted. The judge nodded. "Felix may keep his crayons."

Step 5 · Work the real question

Open PrepTest 116, Section 4, Question 2 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Split the argument into the premise about doing something and the conclusion about a related act. Name the exact gap between them in one sentence. Then test each principle: if it were true, would the conclusion now follow? The winner links the two acts directly, in the right direction. A principle that runs the link the other way, talks about something else, or only hedges will not close the gap.