#13 - Politician: The bill that makes using car phones while

[vas]

Hello,

Thank you for the explanation so far. I had chosen Answer B on this question because I thought that the wording "The only way to reduce the threat to public safety posed by car phones is through legislation" was enough to prove the conclusion. To me, the answer choice used the word "only" (which seemed like strong enough language) and addressed the conclusion (which I think is the first sentence "The bill that makes using car phones while driving illegal should be adopted"). Can you explain why Answer D (not Answer B) is the correct answer again?

Thank you in advance for your help!

[Nikki Siclunov]

Hi vas,

Thanks for your question. I agree that answer choice (B) would be attractive, as it strengthens the conclusion of the argument. However, it does not prove it. Even if the only way to fix the problem is through legislation, that doesn't mean that said legislation should be adopted (which is what the politician wants to do). What if there are downsides to the proposed solution, even if it's the only effective one out there? Maybe the advantages to public safety are outweighed by the disadvantages of curtailing personal freedom.

Here's a similar argument: the only way to ensure that everyone has health insurance is to force everyone, under penalty of law, to get one. Does that mean that mandatory health insurance should be adopted? You are shifting from a descriptive statement of facts (there is only one way to fix a problem) to a prescriptive, opinion-based position (therefore, it should be fixed that way). The former supports, but does not prove, the latter.

By contrast, answer choice (D) contains an imperative ("any proposed law... should be adopted"), leaving no doubt that the conclusion is logically justified.

Hope this helps!

[vas]

Thank you for the extra clarification, Nikki!

[mpoulson]

Hello,

I don't understand why D is more effective at proving the conclusion than B? If the only way to reduce the the threat to public safety posed by car phones is through legislation that seems to be incredible support for validating the conclusion that "the bill...should be adopted". D is simply saying that all laws reducing public safety threats should be adopted which seems to be less specific to the conclusion which is centered around cell phone use. Please help me understand in the simplest way possible. Thank you.

- Micah

[Clay Cooper]

Hi Micah,

Thanks for your question! It is a good one. I will aim for simplicity, as you asked.

I would encourage you to focus on the conclusion: The bill should be adopted.

That, specifically, is what we have to prove; nothing else. How might we prove that? Well, where does it say in the stimulus what qualifies a bill for adoption? It doesn't say at all!

The fact that it doesn't tell us what qualifies a bill for adoption means that we have skipped a step somewhere and made an assumption about which bills deserve adoption. So, now, we just need to connect the evidence we have with the conclusion we're trying to reach.

In other words, what DO we know about this bill? It reduces a threat to public safety. Thus, if we were to prephrase a way to prove the conclusion (or, in other words, an assumption on which the conclusion relies), we might say that any bill which reduces a threat to public safety should be adopted.

Again, that would take us from the evidence we have - that the bill reduces a threat to public safety - to the conclusion that we need to reach - that it should therefore be adopted.

As it turns out, that is exactly what D says, and that is why D is correct.

I hope that helps! Keep working hard.

[mpoulson]

Thank you, I am still having trouble following this logic. What makes B invalid as the answer? I don't understand why it is less effective than D? Is it because B doesn't specifically engage the passing of this specific bill whereas D is a catch all for all Bills? Any advice for ways to improve efficacy on these kind of justify questions?

[Nikki Siclunov]

Hi mpoulson,

Thanks for the follow-up. Before I address your question directly, let me clarify what Clay said in his response:

In other words, what DO we know about this bill? It reduces a threat to public safety. Thus, if we were to prephrase a way to prove the conclusion (or, in other words, an assumption on which the conclusion relies), we might say that any bill which reduces a threat to public safety should be adopted.

As Clay points out, your job is to prove the conclusion. The statement you're looking for is not necessarily an assumption upon which the conclusion relies - these are two different things. A statement that proves a conclusion is a statement that, if true, would be sufficient to establish the conclusion as logically valid. By contrast, an assumption is merely a statement upon which the conclusion depends. Conclusions depend on many assumptions, none of which - if found to be true - would necessarily prove the conclusion.

With that in mind, let's take a look at your two contenders - (B) and (D).

According to (B), the only way to reduce the threat of public safety posed by car phones is through legislation. This clearly strengthens the conclusion, because a bill is a piece of legislation, and apparently it's the only way to get the job done. But, just because this is the only way to achieve your goal does not mean you should do it. The conclusion has a normative dimension - what you should/shouldn't do. It proscribes a certain course of action. Factual statements, such as the one in answer choice (B), can only strengthen such a conclusion, but they can't ever prove it. If you tell me you wanna be rich, and it turns out that the only way to become rich is by robbing a bank, does that mean you should go rob a bank now? No, if only because the ends don't always justify the means. Same thing with this argument: (B) strengthens, but does not prove, the conclusion.

You want a strong, definitive statement when answering Justify questions, that correctly bridge the gap between the premises and the conclusion. Answer choice (D) is perfect in that regard: yes, it would apply to many other laws that improve public safety, but that's not a problem as long as it also applies to the particular law in question. So, if (D) is true, the recommendation presented in the conclusion would also be true. Generally speaking, the only way to justify a normative claim ("should", "must", "ought to", etc.) is with another, similarly normative claim.

Hope this clears things up!

[mpoulson]

Hey Guys/Girls,

This combined response was really helpful. I am recognizing that I have trouble understanding if a question is asking me to Justify or find the (necessary) assumption? Any help for recognizing the difference between the two? I know the lessons give some examples of frequent questions, but sometimes it still seems hard to know and recognizing the difference can be the loss or gain of valuable points. Thank you.

Respectfully,

Micah

[Adam Tyson]

A couple key differences between Assumption and Justify question stems:

1) Justify stems use words/phrases like "allows the conclusion to be properly drawn" or "justifies" or "follows logically". This is "Must Be True" language, in that we are looking for something that is Sufficient to make the conclusion Necessary. Assumption stems tend not to have those words/phrases.

2) Justify stems usually include the word "if", as in "which of the following, if assumed...". Assumption questions don't tend to use that word - "which of the following must the author have assumed", for example.

Take a look in your books at the lessons that cover these two question types, both in the second family (the "help" family), review the different examples of question stems, and look for other key differences. See if you can come up with other themes that differentiate them from one another.

Keep it up!

[Nikki Siclunov]

Hi Micah,

Happy to help.

First, some basic concepts: in Justify questions, you need to identify a statement that is sufficient to prove the conclusion. In other words, if all the answers are true statements, one of them—when combined with the premises in the argument—must be sufficient to prove the conclusion. As you may notice, every variation of the stem instructs you to assume that the answers are true statements ("if true"):

“The conclusion above follows logically if which one of the following is assumed?”
“Which of the following, if true, enables the conclusion to be properly drawn?”
“The conclusion above is properly drawn if which of the following is assumed?”

Let’s work through a simple argument and examine what a Justify answer would sound like:

Premise: Jane just got a 173 on the LSAT.

Conclusion: Jane will be admitted to Harvard.

To justify this conclusion, it is sufficient to say that “Everyone who gets a 173 on the LSAT gains admission at Harvard" (i.e. 173 Harvard). Other examples of Justify answers might include:

• 173 is a top-1% score, and a top-1% score is sufficient to secure admission to Harvard.
• Everyone named “Jane” is automatically admitted to Harvard.
• Everyone who gets a score higher than 165 gets into Harvard.
• Everyone taking the LSAT is automatically admitted to Harvard.

These examples all conform to the following structural paradigm:

Justify Formula: Answer choice + Premise → Conclusion

By contrast, Assumption questions require you to identify a statement upon which the conclusion depends, i.e. a statement without which the conclusion wouldn't make any sense. Typical Assumption question stems include:

“Which of the following is an assumption upon which the argument depends?”
“The argument assumes which one of the following?”

In the Justify answers listed above, none of these statements would be necessary for the conclusion to be true, because the conclusion would be logically valid even if they weren't true.

To identify an assumption, ask yourself this: "What is the least I need to establish in order to ensure that this argument is valid?" In a way, an assumption is an inferential statement: we can prove it by referring to the argument contained in the stimulus, so if the conclusion of the argument is valid, its assumption(s) must be true:

Conclusion (valid) → Assumption (true)

Examples of assumptions for the above-mentioned argument might include:

• At least one person who gets a 173 is admitted to Harvard.
• Jane is applying to Harvard.
• Harvard will not reject Jane’s application for some reason unrelated to her LSAT score.
• The LSAT is one of the factors affecting applicants' chances of admission.

In other words, the statements we just listed must be true if are to believe that Jane will be admitted to Harvard. Indeed, some test-takers find it easier to conceptualize Assumption questions as part of the First Family (i.e. "Prove"-type questions), because the assumption statement can be proven by the information contained in the stimulus.

As you can see, Assumption and Justify questions often require you to find the missing link between a premise and the conclusion: this is why the two question types are conceptually similar. But the way in which the correct answer choice attempts to link the conclusion to the premises varies significantly between them.

Hope this helps!