#22 - Only an expert in some branch of psychology could

[Administrator]

Complete Question Explanation

Must Be True-SN. The correct answer choice is (E)

The first sentence in this counter-intuitive problem can be diagrammed as follows:

• E = expert in some branch of psychology
  
  UIBP = understand irrational behavior of Patrick
  
  
  • Sentence 1: UIBP E

The second sentence also contains a conditional statement:

• E = expert in some branch of psychology
  
  COS = certain of solving someone else's problem
  
  
  • Sentence 2: E COS

Combining the two phrases gives us the chain:

• Sentences 1 and 2 combined: UIBP E COS

In short, that chain means that if someone understands why Patrick is behaving irrationally, then that person is an expert, but that expert is also not certain of solving someone else's problem. We are then told that Patrick wants to devise a solution to his problem.

The question stem is a Must Be True, and one question that should arise to you is what do we know about Patrick? All that we know about Patrick is that he is behaving irrationally and that he wants to devise a solution to his problem. Could he be an expert in some branch of psychology? Yes. We know he wants to devise a solution to his own problem, so is it possible that he understands why he is behaving irrationally? Yes. Does he have to be an expert, or does he have to understand why he behaves irrationally? No. This uncertainty regarding Patrick's exact situation eliminates answer choices (A), (B), and (C). However, that said, this is tricky and counterintuitive! The natural inclination is the think that Patrick is not an expert (because few people would be in this area), but that's not stated here and it is possible he is an expert.

Answer choice (A): This is not certain. Patrick could be an expert and he could understand why he is behaving irrationally.

Answer choice (B): This is also not known. It is possible Patrick is an expert.

Note that if you select this answer choice, then via the contrapositive you would also be forced to select answer choice (A). Any answer choice that appears to make another answer choice correct is automatically incorrect due to the uniqueness of correct answers (there can be one and only one correct answer choice).

Answer choice (C): While this is attractive, this is also unknown. Since the problem is Patrick's, it's not "someone else's problem" and thus perhaps he can devise a solution to his own problem.

Answer choice (D): This answer is incorrect since it offers an opinion ("Charles should not...").

Answer choice (E): This is the correct answer. This answer is the contrapositive of the combined statement above, and can be diagrammed as follows:

• Answer choice (E): COS UIBP (the contrapositive)

[ellenb]

Dear Powerscore,

I had a quick question in regards to the answer choice D, I have read the explanations and it says it is an opinion. What makes this statement an opinion?
Do you have any other examples similar to this?

Thanks

Ellen

[Steve Stein]

Hi Ellen,

Thanks for your question. That one is a discussion of what it takes to understand Patrick's behavior, and what it takes to solve Patrick's problem. One would have to be an expert to understand Patrick's irrational behavior, but no expert can be certain of being able to solve other's problems.

The stimulus dealt not with what should or should not happen (this reflects opinion), but rather what is possible or impossible with regard to understanding and the ability to be certain of a solution.

So, again, it's about the ability to understand behavior, and the ability to be certain of a solution. The problem with answer choice D is that it says Charles should not offer a solution. This is subtle, but it reflects the unsupported opinion that one who cannot be certain of his solution should not even offer a solution.



I hope that's helpful! Please let me know whether that clears this one up--thanks!

~Steve

[skiiam]

Could someone please explain why I made the mistake below? (Why the necessary condition is negated?)

The second condition was: "But no expert is certain of being able to solve someone else's problem"

I diagrammed this as:
~EP -> SSEP
(I thought EP was negated because it said "...no expert is...")
But the answer key tells us it's the other way:
EP -> ~SSEP (where the necessary condition is negated)

EP: Expert in some branch of psychology
SSEP: being able to solve someone else's problem


Thank you

[jeff.wren]

Hi Skiiam,

Anytime you have a negative conditional statement (such as the words "no, no one, none, never, cannot, not both" etc.) the negative (or slash) goes on the necessary condition rather than the sufficient.

For example, the statement "No apples are oranges" is diagrammed: A -> not B. The contrapositive is diagrammed: B -> not A.

In other words, if you know that you have an apple, then you know that you do not have an orange. In plain English, it is saying that something can't be both an apple and an orange.

Many people place the negative in the sufficient, but this is incorrect. The diagram: not A -> O actually means that if you do not have an apple, you must have an orange. In other words, it would be representing the statement that everything that is not an apple is an orange, meaning that everything is either an apple or an orange. This is not what the original sentence means.

A lot of people confuse the "not both" rule with the "either/or" rule. There is a good discussion of these concepts on p. 2-48 to 2-50.

These concepts will also be discussed further in lesson 5 grouping games, when we introduce the double-not arrow.

I hope that this helps answer your question.

Best,
Jeff

[uhinberg]

I rejected answer D because it says "should not." My questions is: If this was a most strongly supported question, and not a validly drawn question, could D have potentially been a good answer. After all, you can infer that someone who is not an expert does not understand the problem, and it is highly reasonable to say that someone who does not understand the problem should not offer a solution.

[Jonathan Evans]

UHinberg,

Good question, and while I'm wary of dealing in hypotheticals, I can reasonably state that the answer is no, this still would not be a good answer. A value judgment such as this with no support in the stimulus has no support without the introduction of extraneous assumptions. Further, the stimulus itself does not lend itself at all to such a "most strongly supported" question. The language here is formal and precise. The questions that look for support generally deal with more "real world" style scenarios. Thus, this particular example does not provide a "minimal pair" (to borrow a linguistic term) between a "most strongly supported" and "must be true" situation. I commend you on the manner in which you're engaging with these questions.

[jwrig9]

I had chosen E until I decided that this is in fact a "Must Be True" question, at which point I decided "Charles" was new information. So I thought it had to be incorrect. Why is Charles not considered new information?

[Luke Haqq]

Hi jwrig9,

To your point about new information in an answer choice, you're certainly right to be on guard because it's a must-be-true question. At the same time, it's possible that a stimulus will draw on/illustrate abstract principles, such that an answer choice could be correct (i.e., would necessarily be true) even if it brings in a new info--so long as the new info illustrates the same principle as the stimulus.

Here, we have conditional reasoning in the stimulus:

Only an expert in some branch of psychology could understand why Patrick is behaving irrationally.

understand irrational behavior expert

But no expert is certain of being able to solve someone else's problem.

expert certain of being able to solve other's problem


Answer (E) must be true because of the inference we can make first by linking the above to conditional statements:

understand irrational behavior expert certain of being able to solve other's problem

And then taking the contrapositive:

certain of being able to solve other's problem expert understand irrational behavior

If Charles--a new actor--is certain of being able to solve Patrick's behavioral problem, then we know that "Charles does not understand why Patrick is behaving in this way" (and we also know that Charles is not an expert).

Hope that helps!

[biskam]

I'm still all around confused why A,B and C are categorically incorrect based on uncertainty, particularly answer C.
I understand that this is a MBT so we're looking for 1 MBT answer and 4 NNT answers (NNT meaning that there's a chance that there's zero or no way that such a case/choice/scenario could occur). So are we saying for choices A, B, C, they all don't HAVE to or MUST be true and thus they're incorrect, even though they might necessarily be true? If this is the case, I don't know see how it could even necessarily be true (unless it's not true at all) that in C "Patrick is not certain of being able to devise a solution to his own behavioral problem." Even if he is an expert, the stimulus says nothing about an expert being certain of their own problems.

Sorry if that's so convoluted. I think I'm getting too complex with this and need some simplification. I understand why E is right based off the CP (I got the q right), now I'm confusing myself with why ABC are wrong