#9 - Rifka: We do not need to stop and ask for directions.

[Basia W]

Good evening,

I have a question about how this question would be drawn up- because of the necessary "unless" indicator I used the unless equation to generate this statement:

Ask for directions Were lost

So I do not see how he arrives at a different conclusion...

Best,

Baisa

[Luke Haqq]

Hi Basia,

You certainly diagrammed the "unless" statement correctly.

Rifka is saying, "If we ask for directions, then we're lost." That doesn't do much for Rifka or Craig in determining whether they're lost. Craig implicitly agrees with the statement because he's recommending that they stop for directions because they are lost.

So they reach different conclusions. RIfka's conclusion is the first sentence: "We do not need to stop to ask for directions," while Craig's conclusion is the opposite.

[Basia W]

Good afternoon,

yes that clarifies it- I should have referred back to her conclusion rather than agonizing over the conditional sentence.

Best,

Basia

[karen_k]

Hi,

I am having trouble understanding why C is incorrect and am confused by what "deny one of Rifka's implicit premises" means on answer choice B. Any insight would be greatly appreciated!

[Anthony Esposito]

Hi Karen,

As you probably know, this is one of those "Method of Reasoning" questions. It's also a good question to try to prephrase so the sneaky LSAT answers don't try to lead you astray.

First, let's look at the correct answer choice, which was answer choice (B). Rifka's implicit premise (meaning "unstated" premise") is that they are not lost. We know this because she tells us that the only time one stops and asks for directions is because one is lost and they do not need to stop for directions.

Craig's statement's "The fact that we are lost . . . " is denying Rifka's implicit premise that they are not lost. I hope that helps.

Let's take a look at incorrect answer choice (C). This is a very, very tricky question, with only 40% of test takers getting it correct. My guess would be that a lot of people selected answer choice (C) as their (wrong) answer.

Does Craig "reject Rifka's conclusion?" Absolutely. Rifka says they shouldn't stop and Crais says they should stop. However, look at the middle of answer choice (C). As we know from our discussion of answer choice (B), Craig does NOT accept the truth of Rifka's premises. Remember, Rifka has an implicit premise that they are not lost lost. In the stimulus, Craig fires back and explicitly states that they ARE lost.

Hope this helps!

Anthony

[karen_k]

Thank you for clearing that up, Anthony!

[cascott15]

Hi Team,

I'm curious if "implicit premises" are something commonly used, or if it was just an anomaly on this test? Reviewing the question, the reasoning clicked, but it threw me off because this is the first time I've seen an implicit premise on the LSAT.

[Adam Tyson]

Definitely not a common phrase on this test, cascott15! In fact, when I did a search for that exact phrase, this was the only question I found that used it. But the idea of an implicit premise is common enough, because that's just another name for an assumption! We could see it called an unstated premise, an implication, a presupposition, etc. So, while the language itself is rare, the phenomenon it describes is one of the most common things on the entire test. Most arguments have assumptions, even if they are not followed by assumption questions.

[LSAT student]

Hello,

Is there any method for identifying unstated premises, such as the one in this problem? What would have helped here. I picked (C) thinking that Craig did accept Rifka's premise, which I identified as "We would not need to stop unless we were lost".

[Rachael Wilkenfeld]

Hi student,

Remember that the definition of an assumption is an unstated premise. Frequently stimuli will have assumptions because there is a gap between the premise(s) and the conclusion drawn. That's really the key to finding unstated premise(s) or assumptions---look for the gap between the premises of an argument and the conclusion of that argument.

In this case the argument goes:

Rifka P: Stop of directions lost.

Rifka C: Not stop for directions.

We are missing an assumption here. The only thing that would require that we don't need to stop for directions is if we were not lost (that's the contrapositive of the premise). It's the jump that we are looking for between the premise and conclusion---that unstated assumption that we need to make the conclusion follow.

Craig picks up on that train of thought---he denies that they are not lost, and specifically says it's because we ARE lost that we need to stop. Craig counters what was unsaid, but what was required by Rifka's argument.

So here, there's a bit of a two step process. First, find the needed assumption, and second, recognize that Craig is denying that assumption.

Hope that helps!