Logical Reasoning · Flaw

PrepTest 129 · Section 2 · Question 4

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

Step 1 · Pre-Question Guidance · read this first

Question type

Flaw

The one idea it tests

One small event is stretched into a sweeping claim about a whole category.

The basic logic

Measure the evidence against the conclusion. The premise describes one incident with a handful of people; the conclusion talks about a huge group 'these days.' That gap is the Tiny Sample flaw.

Tiny words that decide it

“this shows”
“these days”
“several”

Playground logic

Marcus watched two kids at one party cut the cake line while a few others giggled. His top bun: kids these days have no manners at all. His patty is one party and a few kids, which is a Tiny Sample holding up a giant bun.

Step 2 · The kid story

Detective Marcus and the Cake Line

At Nadia's birthday party, the cake came out and everyone lined up. Well, almost everyone. Two kids cut straight to the front, elbows first. A few others laughed and cheered them on. Marcus put on his detective hat, which was a paper party hat. "Case closed," he announced. "This proves that kids these days have no manners. None. Zero." Priya sipped her juice box. "Marcus, there are about twenty-five kids here. Eighteen waited nicely. And this is one party, on one afternoon." "But the cutters!" said Marcus. Lulu tapped her clipboard. "Two kids at one party is not all kids everywhere." Biscuit, who had waited very politely, got a crumb.

Step 3 · Try the model question

Marcus: At one birthday party, two kids cut to the front of the cake line, and a few others cheered them on. This proves that kids these days have no manners.

Which one of these points out the problem with Marcus's reasoning?

Step 4 · The courtroom tale

The Case of the Rude Ice Cream Truck

The prosecutor pointed dramatically. "Your Honor, on Tuesday, one ice cream truck driver honked rudely at a crossing guard. Two passengers laughed. This proves that every driver in this city has become a menace!" Mr. Whitfield rose, adjusting his suspenders. "Your Honor, the city has thousands of drivers. My learned friend has shown us one driver, on one Tuesday, with two giggling passengers." The judge sighed. "That is a very small spoonful to judge the whole carton." "Exactly, Your Honor. One scoop is not the flavor of the entire city." "Objection sustained. And somebody get that crossing guard a sundae."

Step 5 · Work the real question

Open PrepTest 129, Section 2, Question 4 in your official copy from LSAC (for example in LawHub) and read it there.

Your answer

How to apply it

Locate the conclusion and underline how big its group is and whether it covers a whole era or category. Then shrink back to the evidence: how many people or events did the argument actually observe? If the gap is huge, predict 'too little evidence for so big a claim.' Choose the answer describing that gap; reject answers naming moves the argument never makes.