Geek thread - Manhattan LSAT Q & A Forum

[A.Taarabt7]

Hello

I have been studying for the retake and one difference i noticed in the manhattan LR books is that it advocates diagramming for at least the assumption/flaw questions. This is contrary to the prep material i used previously which only advocated diagramming for formal logic questions. Is my intrepretation correct? Should the student diagram as much as possible in LR? in the past I have only done so for formal logic questions, i usually just underline conclusion or use symbols near key pieces of evidence

[Manhattan LSAT Noah]

Hello

I have been studying for the retake and one difference i noticed in the manhattan LR books is that it advocates diagramming for at least the assumption/flaw questions. This is contrary to the prep material i used previously which only advocated diagramming for formal logic questions. Is my intrepretation correct? Should the student diagram as much as possible in LR? in the past I have only done so for formal logic questions, i usually just underline conclusion or use symbols near key pieces of evidence

In general, we advocate diagramming for LR questions in which there's a lot of conditional statements. Those tend to show up in sufficient assumption and inference questions. There are, of course, some flaw questions with a lot of conditional statements.

Overall, from watching various TLS threads, I'd say there's many more people diagramming too many questions than people not diagramming enough. My rule of thumb is that if I can "hold" the conditional logic in my head, then I don't diagram. As the statements pile up, the chance that I'll forget one increases quickly, and I put pencil to paper. Similarly, in RC, the harder the passage, the more I write.

It seems like you're trying to find your footing on this issue, so I suggest you lean towards not diagramming at first, and then when you see a question is stumping you because of those only, unless, and if's, then get to diagramming. That said, if you find you're more successful by diagramming the bajeezers out of the LR section, go right ahead. Now's the time to play around with all of this, and be ready for your approach to change as you get closer to test date and your skills sharpen.

[A.Taarabt7]

thanks Noah, will do.

I am only a few chapters deep right now in the Manhattan LSAT LR book but the reason i ask about the diagramming is due to all the diagramming of the argument core seen in the book. i usually underline or put a C/P next to the material info in problems. when i took the LSAT a week ago i was pretty good on time, i need to particularly drill/master flaw/assumption/must be trues so i can decrease the amount of questions i get wrong on LR, if i could get down to -3 or -2 ill be quite happy since it would be a big improvement ( usually -6 per section).

[dkb17xzx]

I have the Adobe Digital Version for all three books. For some reason, I'm not able to print or save it as a PDF. Is there any way to rectify this? ADV doesn't have continuous scrolling so it's a big hassle.

TYIA

[Manhattan LSAT Noah]

thanks Noah, will do.

I am only a few chapters deep right now in the Manhattan LSAT LR book but the reason i ask about the diagramming is due to all the diagramming of the argument core seen in the book. i usually underline or put a C/P next to the material info in problems. when i took the LSAT a week ago i was pretty good on time, i need to particularly drill/master flaw/assumption/must be trues so i can decrease the amount of questions i get wrong on LR, if i could get down to -3 or -2 ill be quite happy since it would be a big improvement ( usually -6 per section).

We're not advocating that you draw out or write out the core -- we're representing what we should be thinking. Tell me if that's unclear and I'll explain a bit more.

[Manhattan LSAT Noah]

I have the Adobe Digital Version for all three books. For some reason, I'm not able to print or save it as a PDF. Is there any way to rectify this? ADV doesn't have continuous scrolling so it's a big hassle.

TYIA

I'm afraid I don't know about that. E-mail studentservices@manhattanlsat.com - they're quite friendly.

[hallbd16]

So I would like to discuss some of the differences some points on the assumption family. Specifically I am looking at pages 94-100 of the 2nd edition on the topic of sufficiency vs necessary assumptions. Specifically, I notice I have made mistakes of recognizing if something is a premise-booster vs a necessary assumption. I am having a hard time differentiating between necessary assumptions and premise boosters (especially if they restate a premise, because if that premise is proven not true, then the argument clearly doesn't hold up.) I know this is the wrong way to look at it, but I need help re-framing it in my head to avoid this pitfall.

The two questions highlight the heart of my confusion:

On pg 94 with the question PT 22 S4 Q22, on bird dinosaur descendants. AC (C) is not correct b/c it is sufficient not necessary, got that. I eliminated (D) originally though b/c I thought it was a premise-booster. To me the argument already says that the fossils of birds are older than that of the dromesaurs and AC (D) is just boosting that premise. I thought I accept what the stimulus says as 'true.' Upon reflection, it is absolutely clear that this assumption (even if I think it is restating a premise) must be true.

This analysis led to a problem later on in the drill it section on necessary and sufficient assumptions, on question 4 about Maria and faith. The second AC, said that there are no Sundays when Maria is unable to attend church. Well, if this is negated, then there are Sundays when maria is unable to attend church. (Even though I feel this sentence is a premise booster), isn't it necessary for the conclusion to be true? I am perplexed why this example is a premise booster but the example above from PT 22 S4 Q22 is a necessary assumption.

EDIT:
In regards to the second question on Maria and faith, I am thinking that the negation of A doesn't attack the conclusion, because it merely allows for the possibility that Maria might be able to attend church every week, which is still consistent with the conclusion. Is this on the right track?

[Manhattan LSAT Cory]

For those of you asking about printing our e-books: unfortunately this is not possible, which is part of the reason we've made them so much cheaper. If you need the physical material in front of you, you'll have to snag a hard copy.

[matt@manhattanlsat]

I am having a hard time differentiating between necessary assumptions and premise boosters (especially if they restate a premise, because if that premise is proven not true, then the argument clearly doesn't hold up.) I know this is the wrong way to look at it, but I need help re-framing it in my head to avoid this pitfall.

One thing to pay attention to is that we're not looking for something necessary to the conclusion, but rather something necessary to the reasoning of the argument. Remember that assumptions represent the space between the evidence and the conclusion. Typically premises are not necessary to the conclusion, but represent one justification for the conclusion. The conclusion could be true for some reason other than the one offered in the evidence.

This analysis led to a problem later on in the drill it section on necessary and sufficient assumptions, on question 4 about Maria and faith. The second AC, said that there are no Sundays when Maria is unable to attend church. Well, if this is negated, then there are Sundays when maria is unable to attend church. (Even though I feel this sentence is a premise booster), isn't it necessary for the conclusion to be true?

That there are no Sundays when Maria is unable to attend church is not necessary to the conclusion. Maria could be a person who values faith, even if she did not attend church. Another way to think about Necessary Assumptions is that they must strengthen an argument. Anything that fails to strengthen the argument cannot represent an assumption. A claim that represents a premise, or something necessary for a premise to be true, would fail to strengthen the argument. Why? Because in evaluating the validity of an argument, we always concede premises anyways.

On pg 94 with the question PT 22 S4 Q22, on bird dinosaur descendants. AC (C) is not correct b/c it is sufficient not necessary, got that. I eliminated (D) originally though b/c I thought it was a premise-booster. To me the argument already says that the fossils of birds are older than that of the dromesaurs and AC (D) is just boosting that premise. I thought I accept what the stimulus says as 'true.' Upon reflection, it is absolutely clear that this assumption (even if I think it is restating a premise) must be true.

Unfortunately (or fortunately, however you see it), the argument does not say that fossils of birds are older than that of the dromeosaurs. It says that the earliest "known" fossils predate the earliest "known" dromeosaur fossils. That leaves room for there to be unknown dromeosaur fossils that are even older. Something problematic for the argument that the correct answer choice rules out.

Hope that helps!

[Theopliske8711]

I've heard someone tell me that you can treat nec. and suff. assumption as just strengthen questions rather than try to make something particular out of them. What would you say to that? Where might there be pitfalls in treating them as such?

[Fianna13]

I can't find the 3rd edition Lg games guide on the Manhattan website, is it on sale yet?

[matt@manhattanlsat]

I've heard someone tell me that you can treat nec. and suff. assumption as just strengthen questions rather than try to make something particular out of them. What would you say to that? Where might there be pitfalls in treating them as such?

Unfortunately not. It is true that the correct answer to any Sufficient or Necessary Assumption question will strengthen the argument. However, using the criterion of strengthening the argument as the sole means of identifying the correct answer on these questions will not always narrow in on only one answer choice.

Frequently, the test writer will use answer choices that merely strengthen the argument as incorrect answers to either Assumption question. Additionally, while some people do not differentiate between Sufficient and Necessary Assumptions, this too can lead to problems identifying only one answer choice - Noah pointed this out earlier in an earlier post in this thread. Take the question he pointed to about rattlesnakes (PT22, S2, Q22). Answer choices (A) and (E) both strengthen the argument; (A) represents a Sufficient Assumption, whereas answer choice (E) represents a Necessary Assumption.

In short, Sufficient and Necessary Assumptions are two distinct forms of strengthening, and failing to differentiate between Strengthen questions, Sufficient Assumptions, and Necessary Assumptions will leave you torn between answer choices in many cases.

[Manhattan LSAT Noah]

I can't find the 3rd edition Lg games guide on the Manhattan website, is it on sale yet?

They go up tomorrow (Tuesday). Enjoy!

[Manhattan LSAT Noah]

I've heard someone tell me that you can treat nec. and suff. assumption as just strengthen questions rather than try to make something particular out of them. What would you say to that? Where might there be pitfalls in treating them as such?

I agree with Matt that it's good to know the difference between the 3 types of questions, however a confession: I did not differentiate between necessary and sufficient assumptions when I studied, and didn't struggle much with those question types. However, I was a pretty good test-taker from the start, and I think folks that are naturally geeky that way will often find the distinction a bit more categorizing than they need to do. And probably I could have eeked out a question or two more if I had known about all of that. So, if you're doing fine on those question types without all the deep diving into that stuff, don't start thinking you're somehow missing out on the "REAL STUFF THAT WILL CRACK THE LSAT." However, as someone now responsible for other people's LSAT education, I am now all for learning the differences because 1. it strengthens your understanding of logic and arguments 2. you get a stronger grasp of what to expect in each question type, and 3. a stronger grasp which tools you can use (negation for necc., for example).

By the way, in terms of #2 above, you should lower the bar on using "out of scope" for strengthen and necc. assumption answers, as it's not too hard for LSAC to write an answer that gives an example of the assumption. Sufficient assumption answers, however, will almost always feel "just right."

Yes, that was a goldilocks reference.

What I like about your question is that you're onto the connection between these different questions: they're all hinging on the assumption, and you're either asked to identify it or validate it. I think the more you see the assumption family questions as all different flavors of the same snow cone machine, the easier it is to handle them.

Yes, that was an awful analogy about snow cones.

[Fianna13]

I can't find the 3rd edition Lg games guide on the Manhattan website, is it on sale yet?

They go up tomorrow (Tuesday). Enjoy!

Yes! Just in time finishing my thesis proposal. Tomorrow is going to be awesome

[hallbd16]

Awesome. Thanks Matt. Can't believe I overlooked the believe/know/feel flaw. And thanks for the bit on how to think of premise as not necessary for the conclusion. But rather the gaps (assumptions) that are

[lsatkid007]

Hey Noah
Would you please elaborate "Look for strong words in the conclusion and use them to turn the conclusion into a questions." It's in LR guide on p187 in the 2nd edition.

thanks

[Manhattan LSAT Noah]

Hey Noah
Would you please elaborate "Look for strong words in the conclusion and use them to turn the conclusion into a questions." It's in LR guide on p187 in the 2nd edition.

thanks

Sure. Here's a quick example as I'm about to run off for the day: If the arguments states "Because LA doesn't have the same kind of water that NYC has, it will never have high quality pizza" you turn that conclusion into a question: LA will NEVER have high quality pizza? Couldn't there be at least one example of some high-quality pizza out there?

The basic idea is to use the extreme words to identify where the gap might be. Make sense?

[Theopliske8711]

Noah,

Have there been any updates to the RC book? I am looking for some strategies in that section since I am often at a loss at how to go about it (there have been RC sections where I have done -1 or -3 and some where I have done -11; if I can get the -1 or -3, it means, i think, that I have the potential for that; I just need a better focus on how to go about matching the question with the passage). I am looking to pick up the Manhattan RC book but was wondering if there have been alterations to it.m

[Manhattan LSAT Noah]

Noah,

Have there been any updates to the RC book? I am looking for some strategies in that section since I am often at a loss at how to go about it (there have been RC sections where I have done -1 or -3 and some where I have done -11; if I can get the -1 or -3, it means, i think, that I have the potential for that; I just need a better focus on how to go about matching the question with the passage). I am looking to pick up the Manhattan RC book but was wondering if there have been alterations to it.m

The RC book hasn't had any significant changes, so 2nd edition is fine if you have that. We basically did better type-setting on that book. So, if your aesthetic sensitivity is strong, get the 3rd one

[Fianna13]

Is there an E-book version of the 3rd edition LG? I only found the 2nd edition e-book version on the website... and where do we put the promotion code to receive the discount ?

[Manhattan LSAT Noah]

Is there an E-book version of the 3rd edition LG? I only found the 2nd edition e-book version on the website... and where do we put the promotion code to receive the discount ?

The e-book should be out in a matter of months, so I would just get the print copy (and, you're find getting the 2nd edition of the other books, they haven't changed much--but I'd get the 3rd ed. for LG.

We pushed hard to get the print copy done for folks studying for the Dec. LSAT, but our production team is now swept up in some other project...

Lo siento!

[BlackadderIn]

Thanks Noah for the thread!

PT66 LR1 Q17: I got it wrong twice! Looking back, I guess my mistake is that I overlooked the first sentence (twice!), which gives us the important premise that there ARE a lot of illegal copies of Ditalgame --- so a good converting rate of illegal copies to legal copies WILL guarantee a substantial sale increase. So C is the answer.

Is my reasoning correct? Thanks!

[matt@manhattanlsat]

Hi BlackadderIn! If you don't mind, I'll step in for Noah to help out here; we'll be teaming up together on this thread.

Your reasoning is good, but be careful with your wording...

a good converting rate of illegal copies to legal copies WILL guarantee a substantial sale increase. So C is the answer.

A savvy arguer might rebut this point by pointing out that a good conversion rate might not lead to a substantial increase in sales. Why? A new game could hit the market and every gamer could decide that the new game is the only game they want. Likely? No. But possible? Yes.

So rather than saying "guarantee" why not use language like, "support."

Your reasoning though is sound. If answer choice (C) is true, it makes it more likely that people who were illegally copying/downloading the game before would be more likely to purchase the game and so there's reason to believe that we'd see an increase in the game's sales.

Incorrect Answers
(A) provides a strong motivation for Ditalgame to increase its sales, but doesn't tell us how they might actually be able to do so.
(B) provides a possible effect from the fact that people are simply illegally copying Ditalgame's games. But how would this lead to an increase in sales?
(D) provides no impetus for an increase in sales. There's no change here. Ditalgame was well rated before, they're well rated now, so what? A rating of "generally favorable" isn't even that great or better than others. Where's the motivation to go buy Ditalgame's games?
(E) outlines the scope of the problem for Ditalgame, which the copy protection should hopefully solve. And if anything, this might support the premise that Ditalgame has a problem with folks copying their games illegally. But no support is offered for why the copy protection will lead to an increase in sales. Beware of Premise Boosters when working on Strengthen questions. If you're not clear up front what you need to strengthen, these can be tempting.

[BlackadderIn]

Thanks so much Matt! That was really helpful.