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#72939
Complete Question Explanation

Justify the Conclusion SN. The correct answer choice is (E).

The author establishes in the premise that the Sals people had furnaces for smelting, tools of smelted cooper and bronze, and distinct words for copper and bronze, but that they had no distinct word for iron. From this information, the author concludes that the Sals did not smelt iron.

When we are looking to Justify the Conclusion of an argument, we are looking for a way to guarantee the truth of the conclusion, and frequently that means we want to show that the premises we have already been given are sufficient to prove it. That means the correct answer will create a conditional link, wherein the premises are the sufficient condition and the conclusion is the necessary condition. (See Dave's explanation below in this thread for more on how to approach such questions). Here, that means we need an answer in which "they had no word for iron" is sufficient to prove "they didn't smelt iron." More broadly, we'd like an answer that says either "If you don't have a word for something, you don't do that thing" or the contrapositive, which would be "if you do something, you have a word for that thing."

Answer choice (A): Here we are given a Mistaken Negation or Mistaken Reversal of our prephrase (depending on which version of the prephrase you are focused on) - tricky! We don't want having the word to be sufficient for doing the thing; we want doing the thing to be sufficient for having the word!

Answer choice (B): The issue is not whether the Sals were familiar or unfamiliar with iron, but whether they smelted it.

Answer choice (C): This answer simply repeats information we already have about the Sals, and tells us nothing about iron, only about other metals.

Answer choice (D): Another answer that tries to confuse us with the concept of familiarity, when what we want to know is whether they did the thing in question. This answer also makes no link to having or not having a distinct word for something.

Answer choice (E): This is the correct answer choice. A perfect match for our prephrase! If you did the thing, you had a distinct word for it, and since the Sals had no such distinct word this would prove the conclusion that they did not do that thing. Winner!
 Arindom
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#23926
Hi,

The argument says that Sals smelted copper and bronze but nor iron because they had words for copper and bronze but not iron. So, they did not smelt iron.

Then, what is the difference between ans choice A and ans choice E? Is it possible to diagram this even though there are no suff-neccessary indicators?

Thanks.

- Arindom
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 Dave Killoran
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#23998
Hi Arindom,

Thanks for the question! Many Justify questions are built around conditional statements in the answer choices, which is what occurs here. Answer choice (A) and (E) are quite similar and are Reversals of each other (or Negations of each other if you take the contrapositive of one of them).

The argument appears as follows:

  • Premise: No distinct Sals word for iron ( word iron )

    Conclusion: The Sals did not smelt iron ( smelt iron )


    What Justifies that: word iron :arrow: smelt iron

Answer choice (A): ..... ..... ..... word :arrow: smelt

..... This is the Mistaken Negation of what we want.


Answer choice (E): ..... ..... ..... smelt :arrow: word

..... At first glance, this may not appear to be what we want, but if you consider the contrapositive you find it matches our need perfectly:

..... ..... ..... ..... ..... ..... word :arrow: smelt


This almost a perfectly formulaic question, and thus it is one you should study and know like the back of your hand. The premise and conclusion in the stimulus offer conditions, and then the correct answer links those conditions. Understanding this question form will also allow you to anticipate the correct answer using a contrapositive, and answers such as (A) which are mistaken forms of what you want.

Please let me know if that helps. Thanks!
 Arindom
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#24004
Hi Dave,

I can't believe how I missed that! Thanks though for your response!

Best,

- Arindom
 mjb514
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#41971
If A is the mistaken negation then why would we want that? Is there anyway you can further explain this question, I am still quiet confused as to why E is wrong.
 Luke Haqq
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#42074
Hi mjb514,

To see why (E) must be the right answer, let's start with the conclusion: "Thus, the Sals did not smelt iron."

How did the stimulus arrive at the conclusion? The previous sentence gives us the premise being relied on: "There were distinct Sals words for copper and for bronze, but none for iron." In other words, the author of the stimulus goes from the premise "there are no Sals words for 'iron'" to the conclusion that "therefore the Sals did not smelt iron." There's a gap in there--because there's nothing in the stimulus that establishes that the lack of a Sals word for "iron" must imply that iron could not have been smelted by the Sals. Thus we have:
P1: There is no Sals word for "iron"
P2: ???
---
Conclusion: Therefore, the Sals did not smelt iron
Answer (E) fills in that missing premise. Answer (E) states, "If a culture smelted a metal, then it had a distinct word for that metal." (E) would be diagrammed as follows:
culture smelts a metal :arrow: it has a distinct word for that metal
The contrapositive, in turn, of that would be:
culture has a distinct word for a metal :arrow: the culture smelts that metal
In other words, the contrapositive is saying that if there's no distinct word for the metal, then the culture does not smelt the metal. And that gives us the missing premise we needed:
P1: There is no Sals word for "iron"
P2: No distinct word for a metal :arrow: culture does not smelt that metal
---
Conclusion: Therefore, the Sals did not smelt iron

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