Reading comp PrepTest 128 · Section 1 · Question 26
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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AIn the model, the Remaining source text redacted.
Why choice A is not credited
(A) (Lines 42-43) We know from Question #23 and our note about the distinction made by S+O that their system isn’t chaotic, so this answer is wrong in stating that it is.
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BIn a riddled basin Remaining source text redacted.
Why choice B is not credited
(B) Similar to (A), this answer says that particles in the S+O system behave chaotically, when S+O explicitly state in Lines 42-43 that their system is different from chaos.
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CIn the model, it Remaining source text redacted.
Why choice C matches the stem
(C) (Lines 37-41; Lines 26-28) S+O say that in their system, the boundary between the basins of attraction expands to include the whole system - so in a riddled basin of attraction, it’s more limited. On this boundary, the fractal properties make predicting the general destination of a water drop/particle placed there impossible. So for S+O’s system, there’s no place to “drop” a particle where you can predict its general destination; in a riddled basin of attraction, only along the boundary is this true. Therefore, this is the correct answer.
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DIn a riddled basin Remaining source text redacted.
Why choice D is not credited
(D) (Lines 33-36) This answer does suggest that the S+O system is more unpredictable than the riddled basin of attraction, so you should have checked the details in the passage. Doing so would show you, however, that in a riddled basin of attraction, dropping water at an “immediately adjacent point” could result in a different destination, invalidating this answer.
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EIn the model, two Remaining source text redacted.
Why choice E is not credited
(E) The passage doesn’t dive into differences in time, just in location, so this answer is out of scope.
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Discussion
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Why is D incorrect and C correct? 2 replies
Started by Jimmywantstogotolawschool
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Started by thechamp
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Main Idea Q?? 1 reply
Started by gharibiannick