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#25809
Complete Question Explanation

Flaw in the Reasoning. The correct answer choice is (D)

The argument in this stimulus is very complex, with multiple conditional relationships and causal reasoning as well. This is a question designed to eat your time on test day. Diagramming each of the relationships in the stimulus is entirely too costly an exercise to engage in lightly. Instead focus on the conclusion, so that you can cut through the clutter and prephrase efficiently.

The conclusion is the last clause of the last sentence, which tells us that the gardens of those gardeners who have no use for homegrown honey will fail to have excellent pollination. This is a conditional relationship we can diagram as:

HH = use for home grown honey
EP = excellent pollination

  • Sufficient ..... Necessary
    HH ..... :arrow: ..... EP

We were introduced to the idea of excellent pollination in the first sentence, when the author told us that “the presence of bees is necessary for excellent pollination,” a conditional relationship that can be diagrammed as:

Bees = presence of bees
  • Sufficient ..... Necessary
    EP ..... :arrow: ..... Bees
Since the conclusion is telling us there will not be excellent pollination (EP), the conclusion is resulting from the contrapositive of the relationship above:
  • Bees ..... :arrow: ..... EP
The next question is, why does the author think there will not be bees present? Well, the argument tells us that the gardeners will not have beehives. The author is saying that if you do not have beehives, then you do not have bees and, if you do not have bees, then you do not have excellent pollination:
  • beehives ..... :arrow: ..... Bees ..... :arrow: ..... EP
But we have seen the terms “beehives” and “bees” occur elsewhere in the stimulus. In the second sentence, the author told us that “establishing a beehive or two near one’s garden ensures the presence of bees.” We can diagram this relationship as:
  • beehives ..... :arrow: ..... Bees
This relationship tells us that beehives are sufficient for the presence of bees, while the conclusion results from the idea that beehives are necessary for the presence of bees. The argument, then, is proceeding from a Mistaken Negation, assuming that if there are no beehives, then there will not be any bees.

The question stem identifies this as a Method of Reasoning—Flaw question. Our prephrase is that the argument is conditional and flawed, results from a Mistaken Negation.

Answer choice (A): This choice is inconsistent with the stimulus, and therefore fails the Fact Test that is applicable in any Prove Family question. The argument expressly raises another advantage of keeping beehives, namely that doing so ensures the presence of bees, which is necessary for excellent pollination.

Answer choice (B): While this choice describes a flaw in conditional reasoning, it is incorrect because the flaw it describes did not occur in the stimulus. This choice is a trap for those who are simply looking for language pertaining to conditional reasoning without considering the context in which that language is used.

Answer choice (C): As with choice (B), this choice also describes a flaw in conditional reasoning. Again the flaw described in this choice did not occur in the stimulus, which did not contain conditional reasoning pertaining to the abundance of fruits and vegetables. Rather, the language pertaining to fruits and vegetables was causal, i.e., “results in abundant fruits and vegetables.”

Answer choice (D): This is the correct answer choice. This choice describes the Mistaken Negation described above.

Answer choice (E): This choice describes a flaw in causal reasoning, in which a causal relationship between two things is inferred from the existence of a correlation between them. However, the relationship between beehives and pollination described in the stimulus was conditional, not causal.
 karlaurrea
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#6797
I was between answer choices D & E; although I selected the correct one, I would like some further explanation as to what makes E incorrect? The reason why I didn't choose E was because it was hard for me to decide if there really was a causal relationship or not; is that it? There is no causal connection?
 Jon Denning
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#6827
Thanks for the question. Interestingly this Flaw question contains conditional reasoning, not causal reasoning. Note language like "necessary" and "only if." Those are very common conditional indicators, and serve to establish absolute (conditional) relationships between the ideas given.

So an answer like E, which talks about the causal connections in the stimulus, is a trap, where the test makers are hoping you'll confuse conditional reasoning with causal. Compare it to D--which talks about something being "present even in the absence of a particular condition"--and you can see how D is a conditional description, whereas E describes a very different type of relationship.

Definitely an important distinction to keep in mind!
 karlaurrea
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#6829
So is it safe to say, that a flaw question with conditional argument will never have a causal answer choice?
 Brandonhsi
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#18598
Hello,

I was wondering what Pre-phrasing I need before going into answer choices?

Also, there is a lot of information in the premise, but some of them (like in first sentence: causal language) are not relevant in order to save this problem. What steps do I need to think about the premise in order to come up a pre-phrasing? Thanks!

Thanks,
Brandon
 Andrew Ash
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#18610
Hi Brandon,

Good to hear from you again!

Your question of how to effectively prephrase a Flaw question is a good one. In the first place, it's important to recognize that prephrases for Flaw are always a good idea. If you can't spot the problem in the stimulus, it's unlikely that you're going to find it in the answer choices, so it's important that you recognize the problem before you start reading the answer choices. The answer choice that describes that problem is the correct one, whether or not it matches the wording that you prephrased.

In this case, we're looking at an error of conditional reasoning. The author makes two conditional statements in the first two sentences:

Excellent pollination :arrow: bees present

Beehive :arrow: bees present

The conclusion is essentially this:

Not bees present :arrow: not excellent pollination

This relies on taking a Mistaken Reversal of the second conditional statement (so that it reads "Bees present :arrow: beehive"), chaining it with the first conditional statement to get "excellent pollination :arrow: beehive," and then taking the contrapositive. So my problem with the argument is that it makes a Mistaken Reversal of the second conditional statement, and that's my prephrase. The wording of answer choice (D) is surprising, and manages to avoid conditional language (which is unusual for a Flaw answer choice describing a conditional error), but that is the problem it describes, so it's the correct answer.

To answer your second question, it's not always easy to figure out which parts of a stimulus will be relevant to answering a question. In this case, though, since the "abundant fruits and vegetables" aren't related to the conclusion, which has to do with "excellent pollination," I would strongly suspect that they're unrelated, as they in fact are. Also, the problem is the one described above, so that's what I would focus on as I attempt to create a prephrase.

I hope this helps!

Thanks,
Andrew
 Brandonhsi
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#18618
Hi Andrew,

Thanks a lot for your input. It is really helpful. I have one additional question. "Gardener has some/no use of homegrown honey" is mentioned in both conclusion and premise. In view of this, and looking back into the premise, the premise seems to assume "keeping the bee is not economical ---> not to have beehive." I believe it is also the problem of this argument? Therefore, one answer choice addresses this problem, it would be the correct answer as well?

Brandon
 Emily Haney-Caron
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#18622
Hi Brandon,

Thanks for your question! This actually isn't a problem of the argument; the premise you mentioned you diagrammed correctly, but the conclusion is not really making a leap. It isn't saying gardeners with no use for homegrown honey will NEVER have beehives, just that they will tend not to have them, which doesn't really need the premise to support it (it is a reasonable jump to say that people will tend not to do things not in their economical interest, although of course that is not an absolute rule). The much better answer is the one Andrew identified.
 bk1111
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#34932
Hi, would this not be Mistaken Negation. The conclusion is NOT Bee Hive -> NOT excellent pollination. To get to the conclusion, the author is assuming NOT Bee Hive -> NOT Presence of Bees (the Mistaken Negation of the that second statement) and combining that with the contrapositive of the first statement (Excellent Pollination -> Presence of Bees).

Can someone also clarify generally what the answer choices would look like for both a mistaken negation and mistaken reversal in the context of this question?

Thank you!

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