#8 - Linguist: Only if a sentence can be diagrammed

[Administrator]

Complete Question Explanation

Weaken. The correct answer choice is (B).

Answer choice (A):

Answer choice (B): This is the correct answer choice.

Answer choice (C):

Answer choice (D):

Answer choice (E):

This explanation is still in progress. Please post any questions below!

[lmrlmr]

Hi!

Long time listener, first time poster :P

I am getting very confused with this question and generally have issues with similarly worded stimuli. My instinct was to diagram it, but even my diagram didn't seem simple enough. Eventually I understood the flaw they're making (mistakes a necessary condition for a sufficient condition) but I don't think I fully understand how to use that information to lead me to the correct answer choice.

Thank you!

[Beatrice Brown]

Hi LMR! Thanks for your question The tricky thing about these answer choices is that you need to find one that describes what the Mistaken Reversal means, as well as where in the logic the Mistaken Reversal occurs. For a Mistaken Reversal, the author will conclude that a sufficient condition is true on the basis of the necessary condition being true.

In terms of diagramming this stimulus, we can diagram it as follows:
Premise 1: Sentence grammatical diagrammable
Premise 2: Sentence grammatical recognized as such by speakers of language
Premise 3: X's sentence can be diagrammed
Conclusion: X's sentence will be recognized as grammatical by speakers of language

As you pointed out, this is a Mistaken Reversal: the linguist tries to combine the two conditional statements in the premises, and in doing so, makes a Mistaken Reversal in reaching their conclusion. If the sentence is diagrammable, we do not know anything else about it, since "diagrammable" is the necessary condition. But the linguist concludes from the fact that it's diagrammable that it will also be recognized as grammatical by speakers of that language. We can't conclude this, though, just from knowing that the sentence is diagrammable. We need to instead know whether the sentence is grammatical, which the linguist assumes by relying on a Mistaken Reversal of the first premise (i.e., if diagrammable, then grammatical).

To put it another way, imagine if we added the following premise to the linguist's argument: Sentence diagrammable grammatical
If we added this premise, then the linguist's conclusion follows. But since this premise doesn't exist, the linguist is relying on a Mistaken Reversal of the first premise of their argument.

When turning to the answer choices, we want to look for one that tells us that the Mistaken Reversal is not necessarily true. In other words, we need to find an answer choice that says that not all diagrammable sentences are grammatical. Answer choice (B) is a rephrasing of this prephrase. If some ungrammatical sentences are diagrammable, then it would be incorrect for the linguist to conclude that X's sentence will be recognized as grammatical by speakers of the language just from the fact that the sentence is diagrammable. Answer choice (B) tells us that being diagrammable is not sufficient for the sentence to be grammatical.

This is a tricky question, and I hope this helps! Let me know if you need further clarification