These questions are fairly simple. They provide you with a dialogue between two people, and ask for something the two of them definitively disagree on.
The wrong answers will either be things they agree on, or, more commonly, things that they may or may not agree/disagree on and we simply don’t have enough information to determine.
The bottom line is – in order to know that they disagree on something, they have to have both expressed an opinion on it.
Here’s an oversimplified example:
Jack: We should go up the hill to get some water. Also, the Dow Jones will likely rise this month.
Jill: Some of the best jazz is from the 70s. Also, we should stay at the bottom of the hill.
What do Jack and Jill commit to disagreeing on?
The only thing they definitely disagree on is whether or not they should go up the hill to get water. We only know Jack’s opinion on the Dow Jones – maybe Jill agrees with him, or maybe she disagrees. Conversely, we only know Jill’s opinion on jazz – maybe Jack agrees with her, or maybe he disagrees.
Granted, the dialogues presented in the LSAT are usually a bit more sensible and continuous, but I just want to drive home the point that these dialogues are not exhibiting the full scope of opinions held by Jack and Jill as human beings. The only opinions we know they hold are the ones they state explicitly. If an answer choice is something that one or both of the people hasn’t made his/her opinion clear on, then it cannot be the correct answer.
Let’s take a look at an example from June 2007:
Carolyn has essentially made two statements:
- Quinn’s “portrait” of Sulston is replicated fragments of his DNA
- It’s not actually a portrait, since it doesn’t recognizably resemble him
Arnold has also essentially made two statements:
- Quinn’s “portrait” of Sulston is a realistic portrait
- It holds instructions according to which Sulston was created
It’s not hard to predict what the answer is going to be, since these statements only intersect in one place (Carolyn’s second statement contradicts with Arnold’s first statement).
(A) – We have no idea what either one thinks about this, since neither reveals an opinion about what should or should not be called “art”. We just know whether or not they think it should be called a “portrait”.
(B) – They don’t seem to disagree on this. Presumably, they both agree that this is Quinn’s work since they both refer it to him.
(C) – Carolyn clearly thinks the portrait doesn’t recognizably resemble Sulston – her second statement says as much. The question is: what about Arnold? In order for this to be the correct answer, we’d have to know that Arnold does think the portrait recognizably resembles Sulston. He never says that, so it can’t be the answer. (Maybe he agrees, maybe he disagrees.)
(D) – This is wrong for the converse reason that (C) is wrong. Only Arnold reveals his opinion on it, not Carolyn. Arnold clearly thinks that the portrait does contain instructions according to which Sulston was created – his second statement says as much. In order for this to be the right answer, we’d have to know that Carolyn thinks it doesn’t contain instructions according to which Sulston was created. She never says anything about this, so it cannot be the answer.
(E) – Bingo. Carolyn clearly thinks it’s not actually a portrait of Sulston – she says so in her second statement. Arnold clearly thinks it is actually a portrait of Sulston – he says so in his second statement. Therefore, they definitely disagree on this, and it’s the correct answer.
Again, since Arnold never said anything about “recognizable resemblance” and since Carolyn never said anything about “instructions according to which Sulston was created”, we can easily rule out (C) and (D) from being the correct answer. As stated above, whatever they commit to disagreeing on has to at least be something they both talked about in the first place.
This is the best way to predict to answer – break down each person’s speech into statements, and find the statements that intersect/contradict with each other.
The litmus test for knowing whether or not you have the right answer is this: whatever the statement is that they definitively disagree on, you should be able to say that one of them thinks is true and the other one thinks is false. If they’d both say true, or both false, or if you don’t know for sure whether one or the other would say true or false, it can’t be what they definitively disagree on.
For example, in the above question, Carolyn says that (E) is false, while Arnold says (E) is true – that means it’s the right answer. Carolyn clearly thinks (C) is false, but we don’t know whether Arnold thinks it’s true or false. Arnold clearly thinks (D) is true, but we don’t know whether Carolyn thinks it’s true or false.
Here’s another example from June 2007:
Again, let’s break down all the statements made.
Taylor has made two statements:
- Local university researchers claim that 61% of information transferred in a conversation is nonverbal
- This claim, along with all such mathematically precise claims, is suspect, since science could never be that exact
Sandra has essentially made one statement:
- A claim shouldn’t be doubted just because of its exactitude, since science is sometimes capable of producing precise results
This is an easy one: since Sandra has only made one statement, we know the disagreement has to be around that statement! (She spoke two sentences but there is only one novel point made.)
Indeed, Taylor has explicitly disagreed with Sandra’s one statement, in her second statement. Taylor thinks that precise scientific claims should be doubted purely based on their exactitude. Sandra thinks that precise scientific claims should not be doubted purely based their exactitude. The correct answer will have to be paraphrasing or building on this.
Notice that Sandra has not said anything specific to this particular university study or verbal/nonverbal communication. Therefore, as tempting as they are, (A), (B), and (C) can all be thrown out. Sandra has simply said that precision is sometimes obtainable – we have no idea whether or not she thinks that verbal/nonverbal communication study is one of those times, even though we know Taylor’s opinion on all three (false, false, true respectively)
(E) is a confusing statement that doesn’t pertain to what either person says, so it cannot be the answer. In other words, they both might think true or false on this – we have no idea. They simply both talk about whether scientific results should be considered suspect or not – (E) talks about whether the majority of suspect claims end up being false.
That leaves us with (D) which clearly must be the answer. It embodies the disagreement we already pointed out above. Taylor thinks it’s impossible for a scientific study to produce an exact result that is not suspect, while Sandra thinks that is possible. Taylor thinks (D) is false, and Sandra thinks (D) is true.
Now, even though I dismissed (A) through (C) because they mentioned verbal/nonverbal communication, it’s important to realize that the following would have had to be the correct answer if it appeared:
“The local university researchers’ claim about nonverbal communication should be considered suspect on the grounds that it is precise.”
This is a definitive point of disagreement because we know that Taylor would consider this true of any study and Sandra would consider this false of any study. Additionally, had an answer choice said:
“A scientific study showing that eating spinach improves immune function by 45% should be doubted based on its purported precision.”
…then this would also have had to be the right answer! Again, we know that no matter what the study is, Taylor thinks precision is grounds for suspicion, while Sandra does not. In other words, sometimes the right answer is a novel point that can be deduced from the statements on the page. This is rare, but it comes up every once in a while. As long as you think analytically (which you should always be doing on this test) you should be fine.
The point is that whatever the disagreement is, it has to be a function of the disagreement between Taylor’s second point and Sandra’s one point, since that is the only thing they commit to disagreeing over – it doesn’t necessarily have to be taken word for word from the dialogue though, and sometimes can even be an implicit deduction, as my spinach example would have been. However, (A) through (C) are disqualified because they mention specifics of verbal/nonverbal communication, regarding which we do not know Sandra’s opinion.
- The right answer is something the two people definitively disagree on, while the wrong answers are either things they agree on, or (more commonly) things we’re not sure whether they agree or disagree on
- In predicting the answer, it can help to break each of the speeches into statements, and find the statements that overlap/contradict with each other – the answer will have to function on that contradiction
- The litmus test for whether two people disagree on a statement is that one of the two people must definitely think it’s true and the other must think it’s false
- Sometimes, albeit rarely, the right answer will be something that must be deduced from the statements and is not explicitly mentioned; however, no matter what, it always functions on a contradiction between statements of the two people
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