#3 - A cat will not be affectionate toward people unless it

[Administrator]

Complete Question Explanation

Parallel Flaw-SN. The correct answer choice is (E)

This question is a perfect example of flawed conditional reasoning. If you diagram this question (and you should) the first premise says: If A (affectionate) then H (it has been handled). Remember, "unless" introduces a necessary clause, and then you negate the other half of the sentence to form the sufficient clause. The second premise is H, that the cat was handled, and the conclusion is A, that it will be affectionate. This is a mistaken reversal. The reasoning is:

• A H,

then

• H A.

To find a correct answer, we simply have to find another Mistaken Reversal. Also notice that the conclusion in this stimulus is "will be affectionate"; this might help you eliminate answers by doubling the conclusions.

Answer choice (A): Diagramming this answer gives us: PF (produce flowers) C (chilled for two months).

• C PF.

This is the contrapositive, and is, therefore, logically valid and not flawed. Also notice the different, negative conclusion: "not produce flowers"

Answer choice (B): This is simply a restatement of the premises and is, therefore, valid, and not a Mistaken Reversal.

• GW (Beets grow well) CB (contains trace amounts of Boron).
  
  GW CB.

Answer choice (C): Just like answer choice B, this is simply a logical restatement of the premises, and is not a Mistaken Reversal

• PF (produce fruit) PP (pruned properly).
  
  PF PP.

Answer choice (D): Like answer choice A, this is the contrapositive and represents valid reasoning. Double the Conclusion will also eliminate this answer because it is a negative conclusion: "cranberries will not thrive"

• T (thrive) GB (grown in bogs).

The second premise is:

• GB T.

Answer choice (E): This is the correct answer choice. Aha! Here is the Mistaken Reversal repeated. This answer choice exactly matches the flawed reasoning of the stimulus.

• GW (germinate well) PF (pressed firmly into the ground).

Second statement:

• PF GW.

[Johnclem]

Hello,
I just got a quick question for this beautiful question.

I understand that a restatement of a conditional reasoning is valid . But if this were a flaw question would a restatement of a conditional resoning be a circular argument ?


Thanks
John

[Jon Denning]

Hi John - thanks for the question!

The answer is that it depends. That is, the way the argument is put together would determine whether it was a valid restatement of a known conditional relationship, or an invalid "restatement" that's truly circular and flawed.

Let me give you an example of each.

A valid way that this could work, and what we see in answers (B) and (C) of the question that generated this thread, is when a relationship is stated as factual (a premise), and then the sufficient condition is also stated as occurring (another premise). From that you can conclude the necessary would occur, which does indeed "restate" the original relationship, but in a way that has been proven.

For instance, and to use a common example, if you're told that "anyone who gets an A+ had to study," and then you're told that "Carol got an A+," you could rightly conclude that "Carol must have studied." That's the A+ Study relationship two times, but the second time, where the conclusion is presented, is justified/true by the original premise.

On the other hand a circular argument occurs when the relationship itself is concluded solely on the basis of its own information. So someone arguing that "if you want to get an A+ then you better study!" and explaining that belief by saying "because an A+ requires that you study." Or as I sometimes present in class: "Team X is the best team in football. Why? Because they're better than everyone else."

Note that an argument hasn't been built in this case--no reasoning is provided--but merely said twice. When the conclusion depends on itself as support, when it literally assumes as true the very thing/relationship it is trying to prove, you have a circular flaw.

So the difference is subtle but distinctive, and well worth knowing coming test day.

I hope that helps!

[adlindsey]

With questions such as this one, with easily identifiable and heavy use of conditional indicators, is there a more efficient way to work them, besides diagramming? Or will enough practice eventually lead to being able to solve them mentally?

[David Boyle]

With questions such as this one, with easily identifiable and heavy use of conditional indicators, is there a more efficient way to work them, besides diagramming? Or will enough practice eventually lead to being able to solve them mentally?

Hello adlindsey,

Diagramming may often be the most quick and efficient way to solve conditional problems; or at least the most reliable. (Just like with refrigerator repair or putting together a house vacuum, a drawing, a.k.a. "diagram", may make things nicely clear and explicit!)
However, sometimes, as you said, practice may let you solve the problems without diagramming, since you are familiar with the ideas of what "sufficient" and "necessary" are, plus twists like the "Unless Equation". Then you can often look at problems, hopefully, and see what the conditionals are saying without diagramming formally on paper.
So, if you can solve quickly without diagramming, great! Never be afraid to diagram, though, since it may save a lot of misery later on.

Hope this helps,
David