Logical reasoning PrepTest 135 · Section 2 · Question 25

Correct. Argument or Facts:
Facts

Question Type:
Illustration (Principle)

Stimulus Summary:
Incorrect belief - We can't directly access the past, so we can't learn about it
Counterexamples - Multiple disciplines study "current" information to teach us about the past
Caveat - The farther back you're trying to learn about, the less useful the present is

Answer Anticipation:
This Illustration (Principle) question requires us to derive a principle from the stimulus and then find an answer that conforms to it. So let's start by finding that principle!

Here, a mistaken belief is introduced, which won't play a role in the principle since the argument rebuts it. However, we do get an example and a pivot that serves as a caveat or qualification on those examples, so we need a principle that reflects both of those pieces.

It's easy to miss the specifics here, but we can focus on something that we know to be important on the LSAT—the timeline. The stimulus notes that certain disciplines study the present in order to learn about the past ("current [studies are] rich in clues about. . . history"). However, the caveat is that this is less useful as you try to study periods farther back in time. So the principle is something akin to:
We can learn about the past by studying the present, but it becomes less useful the farther back you're trying to learn about.

The correct answer should show examples of a group learning about the past by studying the present and note that it gets less useful as the time period being learned about is farther back in time.

Answer Explanation:
This answer sees astronomers learning about the "earlier years" of the solar system by studying "recently collected" data—in other words, they're using information about the present to learn about the past. Good so far. This answer then goes on to say that they've learned "comparatively little" about the earliest years of the solar system—so they've learned less about something that's the farthest back in time. That lines up with the caveat/qualification on the principle, so this is the correct answer.

Key Takeaway:
Timeline issues are generally important in finding the correct answer when they show up in the stimulus! If you see an argument talking about different time periods, track those shifts.

Incorrect. This answer is about how extensively something has been studied, lacking the timeline aspect from the stimulus.

Incorrect. This answer is about how different world views between two people are, which doesn't necessarily involve the timeline aspect from the stimulus.

Incorrect. There's no timeline issue here, and it's about forming a "rash" judgment, not having something be less useful.

Incorrect. This answer deals with learning about one aspect of the past by studying something that exists in the present, but also in the past. There's no "farther back" because there's only one thing about the past focused on, so this answer is incorrect.