Logical Reasoning · Weaken

PrepTest 137 · Section 3 · Question 13

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

Step 1 · Pre-Question Guidance · read this first

Question type

Weaken

The one idea it tests

If the argument says surroundings have no influence, show a case where surroundings clearly shape the outcome.

The basic logic

Patty: same starting code, different surroundings, same results. Top bun: results come from the code, not surroundings. To pop it, show surroundings do push results around, for example when two with the same code share surroundings and turn out different on purpose.

Tiny words that decide it

“must”
“not subject”
“many”

Playground logic

Marcus's patty: two kids read the same rulebook at different schools and play the game the same way. His top bun: play style comes from the rulebook, not from classmates. Pop it: kids with the same rulebook in the same class deliberately play differently to stand out, so classmates do shape style.

Step 2 · The kid story

The Rulebook Theory

Marcus had a theory about Galaxy Ball. "Nadia learned it from the rulebook at our school. My cousin learned it from the same rulebook in another state. They both play super defensive. So how you play comes from the rulebook. Classmates have nothing to do with it!" Owen scratched his head. Priya sipped her juice box. "What about Nadia and Owen? Same rulebook, same class." Owen grinned. "Nadia plays defense, so I play all offense. I don't want to be her copy." Lulu wrote: Same rulebook, same class, different style ON PURPOSE. Marcus frowned. If the people around you push you to play differently, then the people around you clearly matter. His big theory had a leak.

Step 3 · Try the model question

Nadia and Marcus's cousin learned Galaxy Ball from the same rulebook in different schools, and they play exactly alike. So how a kid plays must come from the rulebook and cannot be shaped by classmates.

Which fact, if true, would most hurt Marcus's argument?

Step 4 · The courtroom tale

Two Bakeries, One Recipe

Prosecutor Lane argued, "Your Honor, two bakeries in two cities bought the same secret recipe book, and both make dense, sweet bread. So the bread comes from the book alone. The local flour mill cannot have influenced it, so the mill's ads were false." Mr. Whitfield rose, suspenders shining. "Then explain the twin bakeries on Elm Street. Same book, same street. One went fluffy on purpose to stand out from the other." The judge raised an eyebrow. "So the neighborhood shaped the bread?" "Exactly, Your Honor. Surroundings do matter." The prosecutor flipped through his notes, looking for crumbs of an answer.

Step 5 · Work the real question

Open PrepTest 137, Section 3, Question 13 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Spot the strong conclusion: the trait comes from the shared starting point and not from surroundings. The evidence is sameness across different surroundings. To weaken, find a choice showing surroundings do shape the trait. Prefer a fact that clearly points to an outside influence. Skip choices about tiny differences, unrelated groups, or facts that fit the argument.