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 mN2mmvf
  • Posts: 113
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#38407
Hi, how should we know to focus on the "all" part instead of the "only" part in "all and only"? When I first read the stimulus, I thought it was arguing that:

approach: only entities explained by the most powerful theory are real
counter: but many entities are posited only for theoretical reasons, and the approach is flawed, thus some of these entities that are not part of the explanatorily powerful theory may be real

I was looking for an answer that would say something like, in fact some theoretical entities are real. (A) isn't quite that, but it's closest. I thought (B) was the opposite of what I expected to be looking for.

Where am I going wrong?
 nicholaspavic
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#38798
Hi nM2,

Remember the conclusion here: "this approach is flawed" (i.e. not all entities posited by the most explanatorily powerful theory of science can be considered real.) You are going to look for the answer choice that fills the gap between that conclusion and the counterpremise that most scientific theories contain entities posited solely on theoretical grounds. In other words, I think you are unduly inferring that the counterpremise suggests that "thus some of these entities that are not part of the explanatorily powerful theory may be real." Definitely focus on all language presented in a short stimulus like this, but also remember that you don't want to make any false inferences. As Nikki suggested previously, it can sometimes be helpful to mark the question and come back to it with fresh eyes at a later point too. Thanks for the great question!
 nutcracker
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#43137
Hello! I'm a little confused by the wording in this question.
I noticed a difference between "the most explanatorily powerful theory of the science" and "most scientific theories", and I think the most explanatorily powerful theory doesn't have to be among the scientific theories that posit entities solely on theoretical grounds. So, even with answer choice B, the reasoning is not necessarily justified, and there seems to be a hole in the reasoning. Did the test makers intentionally leave this hole there just to confuse test takers?
I'd appreciate it if someone can clarify this! Thanks!
 Claire Horan
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#43602
Hi nutcracker,

First, of course these wording differences are there to confuse test takers: That is the point of the LSAT! So when it looks like there is a hole in the reasoning of a question, whatever you are thinking of is intentional more than 99.9% of the time, not testmaker error.

Good job noticing the differences in wording that you pointed out, but the question stem says "does MOST to justify the conclusion." In other words, it is a STRENGTHEN question. If the answer choice does more to make the conclusion more likely than any of the other answer choices, it is correct.

That's why it's so important to determine the question type/what the question is really asking.

Good luck!
 gen2871
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  • Joined: Jul 01, 2018
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#47937
Hi Nikki, in your earlier post you said this:

Approach: Real objects are all and only those entities posited by the most explanatorily powerful theory of science:

The conditional language underlying this approach can be diagrammed as follows:

Real Object --> Entity posited by the most explanatorily powerful theory of science;

Entity posited by the most explanatorily powerful theory of science --> Real Object.

I wonder what made you flipped real object and entity posited by the most explantorily powerful theory of science, do you mean counterpositive: NOT Entity posited by the most explanatorily powerful theory of science --> NOT Real Object? please clarify. I have hard time understanding this part. Thank you!
 Adam Tyson
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#49021
Actually, gen, what Nikki was diagramming wasn't a contrapositive, but both of the relationships set up by the "biconditional" nature of that language. "All and only" is like saying "if an only if" - it sets up a situation where each of the things under consideration is sufficient for the other. "All" indicates a sufficient condition, while "only" indicates a necessary condition, so "all and only" means that something is both sufficient and necessary! Either both things occur, or neither one does. Nikki's diagram was meant to show that the stated relationship actually flows both ways in this stimulus.

Watch out for that rare and tricky "biconditional" language! "If and only if", "if but only if", and "all and only" are the most common ways you will find those relationships being indicated, and when you see them you can interpret them as "both or neither".
 gen2871
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#49036
Adam:

Thank you so much for the clarification!


"all and only"

Real Object :dbl: Entity posited by the most explanatorily powerful theory of science.

Yeah! new information learned! thank you!!
 Mozart
  • Posts: 7
  • Joined: Apr 16, 2020
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#76100
Hello,

I just had a question about answer choice D).
Is this one incorrect because of the word "sometimes"?
If positing entities other than on theoretical grounds only needs to occur sometimes, then perhaps most theories could still be positing solely on theoretical grounds at other times.

Thank you for your help!
 Paul Marsh
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#76205
Hi Mozart! Even if you removed the word "sometimes", (D) would still not be a good answer choice. The author of the stimulus doesn't take issue with entities being posited solely on theoretical grounds; rather, she has a problem with the classification of those entities as real. In other words (according to the author) imagining theoretical objects is probably fine, but classifying those objects as real is definitely not fine. So we want an answer choice with a principle that explains why classifying theoretical objects as real is bad. (D) does not contain such a principle, "sometimes" or no.

Hope that helps!
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 sunshine123
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#96980
Hello,

As I see it, there is yet an ALTERNATIVE set of assumptions that the author COULD have made in making this argument that the correct answer choice and the explanations ya'll provided do not account for. Perhaps the author had in mind that "most scientific theories" that contain entities posited solely on theoretical grounds are DIFFERENT than "the most explanatorily powerful theories" That rendering seems consistent with the stim to me. That assumption, in combination with the assumption that those theories DO posit real entities, would mean the initial approach is flawed, since it is NOT the case that "all and ONLY THOSE" theories that are the most explanatorily powerful yield real entities, since now we have real entities posited by theories OTHER THAN the most explanatorily powerful ones. Does that sound reasonable?? Thanks in advance.

Best,
Dylan Ramirez

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