PrepTest 144
[lcid:3672] Prep Test 144 LSAT — Reading Comp — S1
Reading comp
Passage
. Passage A . Karl Popper's main contribution to the philosophy . of science concerns the power of negative evidence.
Remaining source text redacted.
Passage walkthrough
Passage SummaryTopic: Science
Passage A
Paragraph 1
Paragraph 1
Passage A - Popper's philosophy of science doesn't reflect the reality scientists face, especially with respect to the certainty with which negative evidence can disprove theories.
Passage B - When predicting the orbit of Uranus, scientists were correct in predicting a new planet, but in a similar situation with Mercury, it was actually Newton's laws that were shown to be incorrect.
Key Lines:
Passage A:
Lines 3-5 - An example makes a distinction much clearer
Lines 6-10 - A view is clarified and the Author calls it exaggerated ("hyperbolic")
Lines 17-19 - The Author criticizes the opposing view
Lines 30-32 - The Author clarifies her view, showing a shared viewpoint and an opposed viewpoint with the opposing point
Passage B:
Lines 41-44 - Alternative possibilities are discussed
Lines 48-51 - One possibility is shown to be correct
Lines 53-54 - A similar situation is raised
Lines 58-64 - A different possibility is shown to be correct in this example, with implications for the first
Meta-Structure - Relationship Between Passages:
Rebuttal (Passage A) - The Author of Passage A clearly thinks that Popper's philosophical contribution isn't 100% correct. However, she does clarify this at the end. Popper claims that positive evidence is inconclusive, but negative evidence is definitive in disproving a claim. The Author agrees that positive evidence is inconclusive (though she disagrees with Popper's view that it lacks all value), but she disagrees that negative evidence is always conclusive.
Comparisons (Passage B) - Passage B brings up two similar situations—planets are discovered, their orbits are predicted, and those predictions are wrong. However, the outcome of these situations is different. In the Uranus situation, it ended up being an auxiliary assumption (no other planets in the area) that was wrong. In the Mercury situation, it ended up being Newton's theories that were wrong.
Neutral Author (Passage B) - The Author of Passage B doesn't really take any sides or show any opinion. Rather, he focuses on presenting the details of two separate situations.
How do these passages relate? In a complicated manner! The first passage discusses an approach to scientific inquiry that revolves around positive and negative evidence. How does this apply to the two situations in Passage B? Well, in the Uranus case, the scientists used what they knew to predict an orbit, and that orbit turned out to be wrong. In other words, they made a prediction, and the evidence proved that prediction wrong—negative evidence!
In the Mercury example, they predicted an orbit that turned out to be wrong, so that's more negative evidence. They also then made a prediction that, similar to the Uranus situation, there would be another planet, but they didn't find one—also negative evidence!
(This was a lot of analysis, and we almost certainly wouldn't have walked through all of this ahead of heading to the questions. It's here to help you wrap your head around the passages!)
Also important to note is that the Author of Passage A talks about "auxiliary" assumptions, and Passage B brings these up as a possible place for a prediction made by a theory to go wrong. That overlap aligns the approach in Passage B with that of the Author over Popper.
Last Thoughts:
This comparative set is rough. It's hard to understand, abstract, and definitely outside of most people's area of expertise. So what can you do to make it easier? Rely on that example in Passage A, Paragraph 1. If we can understand what positive and negative evidence is, we should be able to muddle through the detail questions. And as for the Authors' viewpoints, Passage A has some clear statements of opinion, and Passage B lacks a particularly present author.
Passage A
Paragraph 1
- Paragraph note
- A philosopher is introduced, and his theory is explained in depth, focusing on a distinction
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Popper - Theory of negative evidence (vs positive evidence)
- Example - "All swans are white"
- Positive evidence - white swans (can't prove all are white); Popper says no value
- Negative evidence - black swan (one proves idea is wrong); Popper says disproves
- Author - Popper's view "hyperbolic"
- Popper - Negative evidence is core of science (scientific theory → makes predictions testable with negative evidence)
- Paragraph note
- The Author rebuts Popper's argument to some degree
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Author - Popper's view doesn't reflect scientific reality
- False prediction, premise of theory is wrong
- But which one? All theories have "auxiliary" premises from other theories and the real world (e.g., instruments work)
- Author - Popper is right to say positive evidence isn't conclusive; wrong to say negative evidence is
Paragraph 1
- Paragraph note
- A scientific situation is walked through
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Uranus orbit predictions were off, relied on Newton's laws, and auxiliary assumptions (including no other planets were nearby)
- Predictions wrong, so a premise must have been wrong
- Scientists tested other planets around, found that was the mistake
- Paragraph note
- A similar scientific situation is walked through
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Mercury orbit predictions were off, scientists predicted another planet (like with Uranus)
- No planet found, Einstein's new laws matched up with reality, so scientists rejected Newton's theory
Passage A - Popper's philosophy of science doesn't reflect the reality scientists face, especially with respect to the certainty with which negative evidence can disprove theories.
Passage B - When predicting the orbit of Uranus, scientists were correct in predicting a new planet, but in a similar situation with Mercury, it was actually Newton's laws that were shown to be incorrect.
Key Lines:
Passage A:
Lines 3-5 - An example makes a distinction much clearer
Lines 6-10 - A view is clarified and the Author calls it exaggerated ("hyperbolic")
Lines 17-19 - The Author criticizes the opposing view
Lines 30-32 - The Author clarifies her view, showing a shared viewpoint and an opposed viewpoint with the opposing point
Passage B:
Lines 41-44 - Alternative possibilities are discussed
Lines 48-51 - One possibility is shown to be correct
Lines 53-54 - A similar situation is raised
Lines 58-64 - A different possibility is shown to be correct in this example, with implications for the first
Meta-Structure - Relationship Between Passages:
Rebuttal (Passage A) - The Author of Passage A clearly thinks that Popper's philosophical contribution isn't 100% correct. However, she does clarify this at the end. Popper claims that positive evidence is inconclusive, but negative evidence is definitive in disproving a claim. The Author agrees that positive evidence is inconclusive (though she disagrees with Popper's view that it lacks all value), but she disagrees that negative evidence is always conclusive.
Comparisons (Passage B) - Passage B brings up two similar situations—planets are discovered, their orbits are predicted, and those predictions are wrong. However, the outcome of these situations is different. In the Uranus situation, it ended up being an auxiliary assumption (no other planets in the area) that was wrong. In the Mercury situation, it ended up being Newton's theories that were wrong.
Neutral Author (Passage B) - The Author of Passage B doesn't really take any sides or show any opinion. Rather, he focuses on presenting the details of two separate situations.
How do these passages relate? In a complicated manner! The first passage discusses an approach to scientific inquiry that revolves around positive and negative evidence. How does this apply to the two situations in Passage B? Well, in the Uranus case, the scientists used what they knew to predict an orbit, and that orbit turned out to be wrong. In other words, they made a prediction, and the evidence proved that prediction wrong—negative evidence!
In the Mercury example, they predicted an orbit that turned out to be wrong, so that's more negative evidence. They also then made a prediction that, similar to the Uranus situation, there would be another planet, but they didn't find one—also negative evidence!
(This was a lot of analysis, and we almost certainly wouldn't have walked through all of this ahead of heading to the questions. It's here to help you wrap your head around the passages!)
Also important to note is that the Author of Passage A talks about "auxiliary" assumptions, and Passage B brings these up as a possible place for a prediction made by a theory to go wrong. That overlap aligns the approach in Passage B with that of the Author over Popper.
Last Thoughts:
This comparative set is rough. It's hard to understand, abstract, and definitely outside of most people's area of expertise. So what can you do to make it easier? Rely on that example in Passage A, Paragraph 1. If we can understand what positive and negative evidence is, we should be able to muddle through the detail questions. And as for the Authors' viewpoints, Passage A has some clear statements of opinion, and Passage B lacks a particularly present author.
Question prompt
In saying that Popper
Remaining source text redacted.
Why the credited answer is right
Credited answer: D
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Science
Answer choices
-
Aextends the idea to Remaining source text redacted.
Why choice A is not credited
Incorrect. (Lines 8-10) The Author follows up this phrase by talking about the strength of the two types of evidence, not the cases to which Popper's analysis applies, so this answer is incorrect. -
Bunderestimates the significance of Remaining source text redacted.
Why choice B is not credited
Incorrect. (Lines 8-10) The Author says that Popper believes positive evidence has "no value" and negative evidence is "tantamount to disproof"—those are both very strong statements, so she doesn't think he underestimates anything! This answer is also off in stating that Popper's "hyperbolic application" is about how significant his idea is, rather than what it implies. -
Ccommits a logical fallacy Remaining source text redacted.
Why choice C is not credited
Incorrect. (Line 6) This can be a tempting answer—after all, if Popper is engaged in hyperbole, isn't that a logical fallacy? (Hint - It is.) However, we need to be careful about the language in the passage here. What does the Author say Popper gives hyperbolic application to? Logical asymmetry. Does the Author think Popper committed a logical fallacy when reasoning about logical asymmetry? No—she accepts the logical asymmetry as true, as we know because she's the one who presents the example that conveys this simple, fundamental point. And she doesn't say that "Popper argues this proves logical asymmetry" but rather treats it as an established truth in calling it "this logical asymmetry." So while Popper might commit a logical fallacy in reasoning from the idea of logical asymmetry, he doesn't commit a logical fallacy in reasoning about logical asymmetry—positive and negative evidence are logically asymmetrical. -
Ddraws too radical a Remaining source text redacted.
Why choice D matches the stem
Correct. Question Type:
Meaning in Context
Strategy Overview:
Review the purpose of the paragraph in which the relevant phrase is included, then read the statement and surrounding ones, as needed, to get context to define its meaning
Answer Anticipation/Relevant Lines:
Before we even head back to the passage, we should always consider whether the word or phrase in question has any specific meaning or connotation. And here, calling something "hyperbolic" does have a specific meaning and a negative connotation. Saying someone is engaged in hyperbole is to say that they are overstating something, which leads us straight to the correct answer. But let's take a step back and say that we're not aware of that vocab—how would we approach this question?
Let's start by heading back to the phrase in question. There, the Author states that Popper gives the asymmetry between positive and negative evidence "hyperbolic application," arguing that positive evidence has no value and negative evidence provides certainty ("tantamount to disproof"). Does the Author agree with that view? We know she doesn't—she argues against Popper's view in Paragraph 2, concluding that positive evidence is "never conclusive," but "negative evidence rarely is either" (Lines 30-32). So the Author believes that Popper is going too far in stating at least that negative evidence is certain.
Knowing the vocab itself or analyzing it in context leads us to the same conclusion—the Author thinks Popper takes the evidence and goes too far in drawing his conclusion. Let's find an answer reflecting that.
Answer Explanation:
(Lines 8-10; Lines 30-32) The Author states that Popper believes positive evidence has no value, while negative evidence is definitive. However, she concludes that negative evidence is rarely conclusive, showing that she thinks he overstates the certainty there. That counts as drawing too radical a conclusion from the idea, so this is the correct answer.
Key Takeaway:
When you come across vocab that you're not solid on—e.g., if you were confused by "hyperbolic"—look it up, write it on a flashcard, and review it until you understand it. The LSAT isn't a vocab test, but it does tend to reuse vocab. If you get tripped up by a word once, you may see it again, so be sure to learn it! -
Eexaggerates the idea's relevance Remaining source text redacted.
Why choice E is not credited
Incorrect. There's no particular theory presented in Passage A, so this answer is out of scope.