If understanding a word always involves knowing its dictionary definition, then understanding a word requires underst...

Bankole on August 31, 2016

Option A and E

Hi, Please explain why A is incorrect and E is correct

5 Replies

Brendan on July 13, 2017

I would also like to see an explanation for this question. Thank you

Chanlon on September 5, 2017

Could it be dependent on the word ALL in the last sentence, versus the word SOME in answer choice A?

Anthony on October 24, 2017

@mehran, can you break this down for us?

Andrea on November 9, 2017

Can someone explain why E is the right answer?

Mehran on November 13, 2017

Hi all, thanks for your posts. This is an LSAT classic and a difficult question. Let's examine it closely.

We are presented with a Must Be True question. This means that the correct answer choice must follow logically from the stimulus.

First, let's look carefully at the stimulus. It is not an argument, but rather two premises.
P1: KDD ==> WD
[If understanding a word always involves knowing its dictionary definition, then understanding a word requires understanding the words that occur in that definition.]
cp: not WD == not KDD
Notice that this premise sets out a hypothetical condition - IF understanding a word ALWAYS involves knowing its dictionary definition . . . then . . .

P2: B ==> not KDD
[All babies do not know the dictionary definitions of some of the words they utter.]
cp: KDD ==> not B
Notice that this premise is not about the same hypothetical condition as premise #1 - we are not told anything about whether the babies understand the words they utter, only that they do not know the dictionary definitions of these words.

Answer choice (A) says: Some babies utter individual words that they do not understand. This does not have to be true, because the stimulus only tells us about a specific context - a context in which there is an "understanding of the word." We don't know anything about situations where people (babies or otherwise) do not understand a word.

Answer choice (E) says: If some babies [do!] understand all the words they utter, then understanding a word does not always involve knowing its dictionary definition.

This must be true, because we know that all babies do not know the dictionary definitions of some of the words they utter. So if some of those babies understand all the words they utter anyway, then it must be possible to understand a word without knowing its dictionary definition. Put differently, knowing the dictionary definition of a word is not necessary for understanding a word after all.

Hope this helps! Please let us know if you have additional questions.