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#13 - Each of the smallest particles in the universe has...

stsai
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Question: "Each of the smallest particles in the universe..."
I selected (A) although I knew in the back of my mind that if its form stands out, it might be too obvious to be the correct answer...and that skepticism was right.
Is (B) correct because it talks about a physical materialistic character, "metal," instead of an adjective describing the matter at hand that the stimulus and all other answer choices do?
Nikki Siclunov
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That is correct. The flaw in the stimulus is known as the Error of Composition: attributing a property that belongs to each member of a class to the entire class. Your job is to identify the one answer choice that does NOT exhibit the same flaw in the reasoning.

(A) has the same error of composition: the conclusion attributes a property belonging to each part of the car (perfectly engineered) to the car as a whole.

(B), however, is not flawed: indeed, if each part of this desk is made of metal, this desk must be made of metal. "Metal" is a physical, material characteristic, not an adjective describing the matter at hand - like the rest of the answers.

One way to approach this question is to examine the premises in each answer choice and ask yourself, "OK, if this premise it true, does the conclusion need to be true?" Clearly it does not in answer choices (A), (C), (D), and (E) - which is why all of them exhibit an Error of Composition. The conclusion in answer choice (B), however, does need to be true. (B) does not exhibit a flaw in the reasoning and is therefore the correct answer to an EXCEPT question.
Nikki Siclunov
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stsai
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I see. The second approach is helpful too. Thanks, Nikki!
ndc2124
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Difficult question. Please help.

[Question content removed by Admin. LSAC rules unfortunately do not allow the posting of the text of complete LSAT questions. But, if you give us the test date or PrepTest number, the section, and the question number (which I put into the question title), we can find it easily and still answer the question. Thanks!]



Also, whenever a sentence says something happens "at the expense of" something else, does that mean at the expense of whatever happened before the use of the phrase, or whatever comes after it? Or could it mean both? For example,

"Society S gives everyone an equal right to basic liberties, but at the expense of creating inequalities in the distribution of income and wealth. Thus, society S is not just." What does this mean?

Thanks, any feedback greatly appreciated.
Ron Gore
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NDC2124,

I'm not certain if you had a specific question related to the question referenced in the post title, but I figured I'd map out the right way to think about the question and you let follow up if necessary.

This question is a Parallel Reasoning - Flaw EXCEPT question. Your task is to pick the answer choice that does NOT contain an argument with a flawed logical structure similar to that of the argument in the stimulus. In the stimulus, the conclusion that the universe must have an elegant structure was based on the elegance some of its constituents members, i.e., each of the smallest particles.

This logical flaw is known as a error of composition, in which you conclude the whole has a certain characteristic based on information that one of its parts has that characteristic. This concept is related to the error of division, in which you conclude that because the whole has a certain characteristic, then each of the parts must also have that characteristic.

Each of the choices other than (B), which is the correct answer, shares this flaw. (B) is correct because the premise relates the substance of every piece of the desk. If each part of the desk is made of metal, it is valid to conclude that the desk is made of metal. That characteristic is inherent to each piece, and is not simply an opinion regarding it. In each of the wrong answer choices, as in the stimulus, the characteristic of the part is not an inherent quality, but is an opinion regarding it, which does not necessarily translate to a conclusion regarding that quality of the whole (e.g., elegant, nearly perfectly engineered, rectangular, sturdy, well-constructed.

That is not to say it is impossible to have an error of composition when the quality of the part described in the premise is an inherent quality. For example, if you had the premise, "one leg of the table is made of metal," it would be an error of composition to conclude the entire table is made of metal. The distinction here is that the premise referred in answer choice (B) referred to "each part."

As to your question regarding the phrase "at the expense of," as with most things it's best to consider the context of the statement rather than obey a mechanical rule. Here, the phrase reflects that there is a trade-off for gaining a positive. So, in a sentence in which something is gained "at the expense of something else," the expense will a loss by whichever part is not listed as a positive having been received. In your example, the positive received was "the equal right to basic liberties." So, that positive came at the cost, or expense, of "creating inequalities in the distribution of income and wealth."
SLF
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For question, LSAT #53, Section #3, Question #13, would someone kindly explain what makes the 4 incorrect answers wrong...and what makes the 1 correct answer right?
Nikki Siclunov
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Hi SLF,

The original argument contains an error of composition: an attribute of each particle (elegantly simple) is taken to apply to the entire universe. In logic, we cannot infer that something is true of the whole from the fact that it is true of some part(s) of the whole.

Answer choice (B) does not contain the same error, because if each part of the desk is made of metal, then clearly the desk must be made of metal. There is no fallacy here, because the material used to make each part of the desk is not an "attribute," in the same sense that "elegant", "perfect", "sturdy", "well-constructed" or "rectangular" are attributes. The latter are adjectives that may well apply to each part of the whole, but not to the whole itself. By contrast, if each part of the whole is made of the same type of material, then the whole must be made of that material.

Hope this helps! Let me know.
Nikki Siclunov
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SLF
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Thanks Nikki for your excellent insight!
LilyRose
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I have a question regarding this same stimulus/answer choices:

It is clear that the stimulus contains a part-to-whole flaw. The stem asks us to identify the one answer choice that does not contain that same flaw. As far as I can tell, both B and D actually satisfy that: B in that each of the answer choices except for B contain an abstract attribute/descriptor, rather than a physical characteristic. B is the only one to contain that 'physical characteristic' type of descriptor, so it doesn't really match the others.

However, D differs from the others. A, B, C, and E all display a general part-to-whole logic, and D does not contain this same pattern of logic. Rather than "All parts are X, so the whole is X," D contains "All parts that are Y are X, so the whole is X." Rather, it does not say, 'each piece of this chair is sturdy, so the whole chair is sturdy'; it specifies, 'each piece of wood in this chair is sturdy.' It doesn't really suggest that the whole chair is made out of wood, so it isn't exactly the same pattern of logic.

I chose D because it seemed like the more egregious break from the pattern. Why would this not be considered a "different" flaw than that exhibited by the stimulus?
Nikki Siclunov
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Hi LilyRose,

I understand your reasoning for disputing whether (D) exhibits flawed reasoning similar to that in the argument contained in the stimulus. Your objection is that the chair may not be made entirely of wood, and so the members (the pieces of wood) that comprise the whole class (the chair) are not collectively exhaustive of all things that can possibly comprise that class (what if the chair also has steel supports, a metal frame, etc.)?

Unfortunately, the original flaw in the argument does not require that the members of the class represent a collectively exhaustive set. The particles compose the universe, the author said, but there is no reason to believe that the universe is composed of only the smallest particles (just like the chair may not be composed entirely of wood). What about dark matter, larger particles, etc.?

Some of the other answer choices that adequately parallel the flaw exhibit a similar nuance. Take answer choice (C), for instance: each brick in the wall is rectangular. Obviously, the wall is composed of more than just bricks. There is mortar, support joints, plaster, etc.

The Error of Composition does not require that the elements whose characteristics allegedly apply to the entire class be collectively exhaustive of all elements that can possibly comprise the class. In fact, the more unique or unrepresentative these members are of the entire class, the more egregious the fallacy.

Hope this helps!

Thanks,
Nikki Siclunov
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