Reading comp PrepTest 128 · Section 1 · Question 24
Passage
Passage walkthrough
Topic: Science
Paragraph 1
- Paragraph note
- Old Belief; Reason to question it
- Views, minor Meta-Structures, and the author's attitude
- Foundational belief of science - Experiments can be replicated to prove results
- Sommerer/Ott -Smallest change results in different outcome
- Computer model - Particle in force field
Paragraph 2
- Paragraph note
- S+O analogy (riddled basins of attraction)
- Views, minor Meta-Structures, and the author's attitude
- Computer model based on analogy - Riddled basins of attraction
- Basin of attraction - Drop water on land surrounded by 2 bodies of water, will end up in one of them
Paragraph 3
- Paragraph note
- More on analogy
- Views, minor Meta-Structures, and the author's attitude
- Some places, line between basins of attraction impossible to see
- Only way to know where water goes is to drop it and watch
Paragraph 4
- Paragraph note
- Bring analogy back to original system; Distinction (S+O system vs. chaos)
- Views, minor Meta-Structures, and the author's attitude
- S+O system - Like riddled basin of attraction, but line between basins is throughout whole system - can’t tell even general destination without dropping particle
- Chaos - Could tell general destination but not exact destination or path
- (So S+O system is...more chaotic than chaos?)
Paragraph 5
- Paragraph note
- Author extrapolates
- Views, minor Meta-Structures, and the author's attitude
- S+O’s system is first they tried, so likely there are other systems that have similar features
- If that’s the case, then scientists have to rethink failed replication experiments
Main Point: Sommerer and Ott’s research suggests that experiments that fail to have their results replicated could be working in a system where replicating results is nearly impossible.
Key Lines?Lines 1-4 - Fundamental assumption of science
Lines 4-8 - Scientists call it into question
Lines 12-14 - An analogy to help understand the scientists’ experiment is introduced
Lines 37-41 - The original experiment is discussed
Lines 42-46 - A distinction
Lines 47-50 - Extrapolation to other systems
Lines 52-57 - Author notes implication if S+O’s system is common
Meta-Structure?Old Belief/New Belief - The Author kicks the passage off by talking about one of the “foundations” of science - experimental results need to be replicated to be credible. This suggests an Old Belief/New Belief passage, which is reinforced when she then pivots (“But”) to talking about the work of two scientists who have shown that there are systems where “even the least change in starting condition” can lead to a different outcome. In other words, they show that, for some systems, the original result might be right even if it can’t be replicated because of minor variations in “starting conditions.” She spends the next few paragraphs diving into the research in detail before extrapolating and bringing up an implication from it in Paragraph 5. There, she states that there are likely more systems like the one Sommerer and Ott found (Lines 47-50), and that if there are, the scientists will be “forced to question” the foundation from the first line. This is a New Belief, even if it’s highly qualified (“If other such systems…”). When a passage falls into an Old Belief/New Belief Meta-Structure, the Author’s opinion of the New Belief is the main point. Here, she’s not 100% on board, but she certainly believes that Sommerer and Ott’s research might be representative of other systems, and if that’s the case, it’d cause a fundamental shift in science, which is the main point of the passage.
Last Thoughts?This is a super difficult passage. You have to first understand the distinction between basins of attraction and riddled basins of attraction from Paragraphs 2 and 3 before you can then use that analogy to understand Sommerer and Ott’s system that is similar to the latter. There’s a lot of scientific terminology scattered throughout, as well. So be sure, when presented with an analogy for a difficult concept, to understand that analogy and how it informs your understanding of the difficult concept.
Here, seeing that there’s a distinction between basins of attraction and riddled ones is key. The basin of attraction is defined in Lines 20-22. That is distinguished from “some geographical formations” that are “riddled” with notches and zigzags, making it impossible to predict where water will end up (Lines 23-30). So, in a normal system, you could predict at least somewhat where the water would end up, but not in a riddled basin of attraction. That’s what’s analogous to the system made by Sommerer and Ott, where the entire system is notches and zigzags, and the only way to know where the particle will end up is by running the computer simulation.
Note the strong language we see there - e.g., “impossible.” That’s pretty strong language, and we see other examples throughout the passage (e.g., “literally the first,” Line 49). For this passage, we should be more willing to pick stronger answers than average.
Finally, note the distinction drawn in Paragraph 4. The system that Sommerer and Ott have created is one where it’s “impossible to predict” even the general destination of the particle. In a “chaotic” system, the general destination is predictable, even if its path and exact destination aren’t. That means most people would define Sommerer and Ott’s system as even more chaotic than chaos! That’s definitely messing with the definition of the word “chaos” as most people understand it, so we should note this distinction and definition, as it’s likely to show up in a question or be used incorrectly in a trap answer.
Question prompt
Why the credited answer is right
Credited answer: C
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Strategy Overview
Answer Anticipation
Answer choices
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AIt is sometimes impossible Remaining source text redacted.
Why choice A is not credited
(A) (Lines 26-28) In describing a riddled basin of attraction, it’s said that the boundaries between one basin and another are riddled with fractal properties. However, there’s no indication that it’s “sometimes impossible” to tell if such fractal properties exist in a system, so this answer is out of scope.
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BIt is sometimes impossible Remaining source text redacted.
Why choice B is not credited
(B) (Lines 43-46) We just looked up the definition of “chaos” for Question #23, so we should be able to find it in Paragraph 4. There, it’s stated that in a chaotic system the general destination is predictable, so this answer is contradicted by the passage.
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CIt is sometimes impossible Remaining source text redacted.
Why choice C matches the stem
(C) (Lines 52-57) This answer lines up with the main point of the passage. A foundational view of science is that experimental results can be recreated. However, S+O ran experiments to show that systems exist where the tiniest change in starting conditions can change the outcome, which challenges the view of whether a failed replication can invalidate original results. This answer reflects that general point made in the passage, so it’s correct.
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DIt is usually possible Remaining source text redacted.
Why choice D is not credited
(D) (Lines 20-26) The passage states that in a riddled basin of attraction, it’s impossible to predict even which body a drop of water will end up in, suggesting that in a basin of attraction not along the boundary, you could predict that. However, it never states that you can predict the path along which that water will travel, so this answer is unsupported.
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EIt is usually possible Remaining source text redacted.
Why choice E is not credited
(E) (Paragraph 4) The whole point of Paragraph 4 is highlighting how unpredictable things are in S+O’s system, so it’s unlikely that they’d argue the path could be determined given only two pieces of information.
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Discussion
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Confused 2 replies
Started by hassay18
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Why is B incorrect? 3 replies
Started by Shiyi-Zhang
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Explanation 3 replies
Started by DanielDePasquale