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#26305
Complete Question Explanation

Method of Reasoning—AP, SN. The correct answer choice is (C)

The argument points out that any theory that is to be taken seriously must affect our perception of the world. In other words, to be taken seriously it is necessary that the theory affect our perception:
  • Premise: ..... Taken seriously ..... :arrow: ..... Affect perception
The author goes on to state, however, that affecting our perception of the world is not enough for a theory to be taken seriously, i.e. it is not a sufficient condition to make us take the theory seriously. Astrology is then provided as an example that illustrates this claim. In other words, it is a theory that does affect our perception of the world, but which should not be taken seriously. Prephrasing the completion of the sentence in the question stem is essential to attacking this question quickly and efficiently!

Answer Choice (A): This answer choice is half-right and half-wrong. While astrology should not be taken seriously according to the stimulus, it does affect our perception of the world. Answer choice (A) claims that astrology does not affect our perception of the world. Since the latter half of this answer choice does not accurately describe the stimulus, it is incorrect.

Answer Choice (B): The author never stated that astrology should not be considered a theory. Astrology was an example of a theory that should not be taken seriously.

Answer Choice (C): This is the correct answer choice. Astrology is a theory that affects our perception of the world, yet should not be taken seriously.

Answer Choice (D): Once again, this answer choice is half-right and half-wrong, and therefore incorrect. While it is true that astrology affects our perception of the world, it should not be taken seriously. This answer choice states that it should be taken seriously.

Answer Choice (E): This answer choice is reversed. It states that astrology should be taken seriously even though it does not affect our perception of the world. The answer choice should state that astrology should not be taken seriously even though it does affect our perception of the world.
 timm2985
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#11765
I would appreciate ANY help on this problem!

Question 7: The main issue I have with this problem is not the conditional logic. I consider myself pretty well-versed with conditional logic. However, this question continues to bother me.
Why is the answer not (E)? If Astrology should be taken seriously, however, it does not meet the one necessary condition of affecting our perception of the world... why is this not correct? I understand that the Scientist qualifies his first premise by stating that another necessary condition must be present in order for a theory to be taken seriously. Then he gives an example of astrology to make his point. I interpret the astrology example to mean that this theory should be taken seriously since it must affect our perception of the world, AND something else...??? Also, if anyone knows a similar question, please let me know.
 Ron Gore
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#11774
Hi Tim,

This is a Method of Reasoning question, and your task here is to select the answer choice that best describes what is stated in the stimulus.

In this case, the stimulus has three statements.

Sentence 1 is a conditional relationship: "any theory that is to be taken seriously must affect our perception of the world." You could diagram this relationship as:

..... theory to be taken seriously ..... :arrow: ..... affect our perception of the world

Sentence 2 does not present a new relationship, but merely states that "this," a reference to affecting our perception of the world, is not sufficient for a theory to be taken seriously. This is not an entirely new piece of information, in that by default a necessary condition is required, not sufficient. It does, however, tell us that a theory affecting our perception of the world is not both necessary and sufficient (i.e., in a bi-conditional relationship) for a theory to be taken seriously.

Sentence 3 is somewhat ambiguous, but from the context appears to be referring to the second sentence. The scientist is saying that to see that "affecting our perception of the world is necessary for a theory to be taken seriously, but is not sufficient for a theory to be taken seriously," one need only consider astrology. Thus, the scientist implies that astrology is an example of a theory that affects our perception of the world but should not be taken seriously.

Your Prephrase for the correct answer is that the scientist's point in mentioning astrology is to show an example of a theory that affects our perception of the world but should not be taken seriously.

The correct answer choice, (C), is a restatement of this Prephrase.

You asked about answer choice (E), and why it is incorrect. Specifically, you said:
timm2985 wrote:If Astrology should be taken seriously, however, it does not meet the one necessary condition of affecting our perception of the world... why is this not correct? I understand that the Scientist qualifies his first premise by stating that another necessary condition must be present in order for a theory to be taken seriously. Then he gives an example of astrology to make his point. I interpret the astrology example to mean that this theory should be taken seriously since it must affect our perception of the world, AND something else...???
Answer choice (E) says the scientist presents the example of astrology to show a case in which the rule he presented in his first sentence is violated. This is incorrect, because the language in the stimulus shows that the scientist views astrology as an example that is in conformance with the rule.

The rule presented by the scientist in the first sentence was that in order for a theory to be taken seriously, it must affect our perception of the world. In answer choice (E), astrology is said not to affect our theory of the world. By the rule, it should not be taken seriously as a theory, contrary to the first clause of answer choice (E).

It appears that you interpreted the stimulus as requiring two necessary conditions for a theory to be taken seriously. As implied by the discussion of the stimulus above, your interpretation is incorrect. However, even if it were correct, answer choice (E) would not conform with your view. If the scientist positioned "affect our perception of the world" as one of two necessary conditions, the failure of astrology to affect our perception of the world would still require that astrology not be taken seriously as a theory.

Whenever you have a compound necessary condition, such as:


..... ..... ..... ..... ..... B

..... A ..... :arrow: ..... AND

..... ..... ..... ..... ..... C

then the failure to satisfy either necessary condition is enough to show A must not be the case:

..... B

..... OR ..... :arrow: ..... A

..... C

Under the rule presented by the scientist in this stimulus, the failure of astrology to affect our perception of the world would be enough for us to know it should not be taken seriously as a theory.

Respectfully, while I understand you to believe that you fully understand conditional reasoning, it appears to me, having now seen your approach to conditionality in this post and in your post about fruit trees that you might benefit from some review of the topic.

Please let me know if this response helps, or if you need further assistance.

Thanks,

Ron

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