LSAT tricks youve accumulated Forum

[Cal.1985.Seth]

trick is to take a breath and slow down when you are stuck. SLOW DOWN and be confident that YOU KNOW how to do it. Really, you do. Just think through it calmly.

[JazzOne]

Hi guys...so for some reason I do really well in the LR with the first 17 questions...but 18-25/6...i get atleast half of them wrong!!...Mainly I have realized why I get those wrong is because one always is Parallel reasoning and another is Assumption question...The assumption that the author is making is hard to find when it deals with a question from the last few questions....Any special tricks that you can advise me on??....i know about the denial test...but when its harder questions, its harder to use the denial test!...please help!

Many of my students refuse to use the negation test (or denial test, as you call it) on the easier problems. They say, "The answer was obvious. I didn't need the negation test." Then they get to a hard question, and they can't understand how to use the negation test. You have to practice the denial test on the easy questions so that you truly understand how it works. You have to practice negating easy statements before you can negate difficult statements. I suggest you go back and practice the denial test on every necessary assumption question you can find. That will help you when you come across more complicated statements and questions.

[tram988]

Good idea jazz. And by applying the technique, you mean negating each answer choice to see if it weakens the argument? And the choice that does weaken the argument is the correct choice, right?

[JazzOne]

Good idea jazz. And by applying the technique, you mean negating each answer choice to see if it weakens the argument? And the choice that does weaken the argument is the correct choice, right?

You are mostly correct. I would go one step further. Negating the correct answer should RUIN the argument, not just weaken it. Here's why:

They are asking for a necessary assumption. So we could diagram the argument and assumption through this statement: "If the argument is valid, the assumption is true."

Valid argument ---> Assumption

So the contrapositive is:

~ Assumption ---> ~ Valid argument

[savagedm]

One other thing that really helped me with PR questions is to break the argument down in VERY simplistic terms. Like basically reword a huge passage in my head to "you need plentiful good food and friendly guests for a good party, so and so has plentiful food and friendly guests so there will be a good party". The flaw of course being that their food is not mentioned to be GOOD. So just look for a similar flaw which leaves out that crucial factor to the two necessary conditions for the party.

[isaaca]

I recently realized this, but someone correct me if i'm wrong.

When the answer choice contains an if/then statement, it is almost always (99%) wrong EXCEPT in assumption questions. So, in any other question types, it won't fly...

Is this correct?

[blhblahblah]

I recently realized this, but someone correct me if i'm wrong.

When the answer choice contains an if/then statement, it is almost always (99%) wrong EXCEPT in assumption questions. So, in any other question types, it won't fly...

Is this correct?

Dude, why even bother quantifying the likelihood that answer choices which contain xyz are not likely to be right on questions xyz? a) no one here has enough statistical data to even remotely support such a conclusion b) taking short-cuts do not help you understand the underlying logic of the test c) there could be a credited response you overlook as a result of that short-cut

[blhblahblah]

hk brought up a neat denial trick for sufficient assumptions where you negate the conclusion of the stimulus and the consequence of that negation means that credited answer choice must be false.

Put differently, sufficient assumptions, when accepted, mean that the conclusion must be true. But if the conclusion in a stimulus is negated, then any sufficient assumption which allows that conclusion to be properly drawn must be false.

[Lyov Myshkin]

hk brought up a neat denial trick for sufficient assumptions where you negate the conclusion of the stimulus and the consequence of that negation means that credited answer choice must be false.

Put differently, sufficient assumptions, when accepted, mean that the conclusion must be true. But if the conclusion in a stimulus is negated, then any sufficient assumption which allows that conclusion to be properly drawn must be false.

aw thanks buddy..

[blhblahblah]

hk brought up a neat denial trick for sufficient assumptions where you negate the conclusion of the stimulus and the consequence of that negation means that credited answer choice must be false.

Put differently, sufficient assumptions, when accepted, mean that the conclusion must be true. But if the conclusion in a stimulus is negated, then any sufficient assumption which allows that conclusion to be properly drawn must be false.

aw thanks buddy..

I never use it, though.

[Lyov Myshkin]

hk brought up a neat denial trick for sufficient assumptions where you negate the conclusion of the stimulus and the consequence of that negation means that credited answer choice must be false.

Put differently, sufficient assumptions, when accepted, mean that the conclusion must be true. But if the conclusion in a stimulus is negated, then any sufficient assumption which allows that conclusion to be properly drawn must be false.

aw thanks buddy..

I never use it, though.

lol, i don't think i have either.

[blhblahblah]

hk brought up a neat denial trick for sufficient assumptions where you negate the conclusion of the stimulus and the consequence of that negation means that credited answer choice must be false.

Put differently, sufficient assumptions, when accepted, mean that the conclusion must be true. But if the conclusion in a stimulus is negated, then any sufficient assumption which allows that conclusion to be properly drawn must be false.

aw thanks buddy..

I never use it, though.

lol, i don't think i have either.

I dont think anyone has...It's just one of those intellectual discoveries which garners a lot of awe but bears little to no pratical application...

[Lyov Myshkin]

I dont think anyone has...It's just one of those intellectual discoveries which garners a lot of awe but bears little to no pratical application...

lol. lsat academics..

[Rsrcht]

I dont think anyone has...It's just one of those intellectual discoveries which garners a lot of awe but bears little to no pratical application...

lol. lsat academics..

Still, it's a good method of making one answer stick out from the rest. Negate the conclusion, then use POE on all of the could-be-trues.

[b1650]

If you're taking the LSAT you should read this...it'll make you feel better


--LinkRemoved--

[LjakW]

If you're taking the LSAT you should read this...it'll make you feel better :lol:


--LinkRemoved--

It irks me each time the author calls Logic Games "Logical Games"

[northorbetter]

That may be a good tip, but you want to make sure the question actually deals with conditional reasoning. There was a question in PT 43, 44, or 45 that was causal, and it stuck in an answer choice that contained the words "sufficient" and "necessary".

Contained both of them in the answer? I haven't seen that, but seeing both words in one answer choice would definitely give me pause.

And, yeah, you're absolutely right about making sure it's conditional.

Will the conditionality in the stimulus be obvious or will some sort of sufficient indicator be enough to apply the afore mentioned rule/trick?

[TheTopBloke]

If anyone else has any tips on parallel reasoning, please share. If there's a parallel reasoning question anywhere between question Nos. 20-25/6, I'll get it wrong 90 percent of the time.

These used to kill me and I still save them for last. However, the best thing I read on this site was to just isolate the conclusion first and look for key language, such as "does not" or "is likely." Then jump to the answers and quickly dispense with answers that do not have the same conclusive reasoning. From there, it's usually down to only two-three answers that you have to slug through. Isolate the premises and make sure they support the conclusion the same exact way the stimulus does. The language is key again, just don't be fooled by premises and conclusions that look different but have the same meaning (like contrapositives).

Since I am usually trying to wrap up the section by the time I get here, I just focus on the similarities of the conclusions. Pay attention to words like "if" "does" "will" etc. as they become extremely important on these questions. The conclusion's purpose is what's most important. Think to yourself: is this predicting something, suggesting something, refuting a claim?From there, just make sure the premises match up and you're golden.

I found the LR bible helpful on this one. You must look for the conditional reasoning or causal reasoning. Diagramming may help you. I found I don't actually need to write a diagram as long as I bear in mind the symbolic relationships and attempt to look for those in the correct answer.

BTW PT 26 Sec 3 can suck it. Last Q I got wrong simply because I didn't take the insurance answer, I took the library answer. I am improving but after using the bible books I have become so literal I am missing Q's that have real world reference in them. But again, I have improved.

[nycparalegal]

BUMP any new tricks from the TLS crowd?

[Sandro]

WOW! Re reading the Parallel Reasoning section makes it infinitely easier to solve these problems - I was going at it just by abstraction or diagramming... using the premise and conclusion methods make it much easier and allow to use abstraction as a last resort on harder problems.

[dynomite]

1) The word "unless" seems to mess people up. I change it to "if not," then make that part the first piece of the conditional statement.

I won't pick you up at the airport unless you pay me. --> I won't pick you up at the airport if not you pay me.

So...

[strike]Pay me[/strike] --> [strike]Pick up[/strike]

Contrapos:

Pick up --> Pay me

2) "if and only if" also confuses people. Simplify it by making it an entity block.

"A if and only if B" --> [AB]

You can't have one without the other.

[Shrimps]

'unless' implies a necessary, not a sufficient condition

I won't pick you up at the airport unless you pay me: I will pick you up --> you pay me (contra: you don't pay me --> I won't pick you up). Think about it. There are many other reasons why you cannot pick someone up at the airport.

If you pay me, I will certainly pick you up is the opposite: you make payment a sufficient condition.
You pay me --> I will pick you up

[theZeigs]

1) The word "unless" seems to mess people up. I change it to "if not," then make that part the first piece of the conditional statement.

I won't pick you up at the airport unless you pay me. --> I won't pick you up at the airport if not you pay me.

So...

[strike]Pay me[/strike] --> [strike]Pick up[/strike]

Contrapos:

Pick up --> Pay me

'unless' implies a necessary, not a sufficient condition

I won't pick you up at the airport unless you pay me: I will pick you up --> you pay me (contra: you don't pay me --> I won't pick you up). Think about it. There are many other reasons why you cannot pick someone up at the airport.

If you pay me, I will certainly pick you up is the opposite: you make payment a sufficient condition.
You pay me --> I will pick you up

You're both right. For people looking for another discussion of this, see: http://www.top-law-schools.com/forums/v ... 6&t=105534 with my link in my first post as well.

Unless/Except etc. become tricky when you have two conditions involved with the "unless", see the thread above. For example "I won't go to the game unless the cheerleaders and the concessions are there."

Using Shrimps: Go to game --> concessions AND cheerleaders
Using Dynomite: if not concessions OR cheerleaders --> won't go to game (contrapositive: go to game --> concessions AND cheerleaders)

They're equivalent but you just have to make sure you have the "Unless/Except" situations as a muscle memory.

[skip james]

'unless' implies a necessary, not a sufficient condition

I won't pick you up at the airport unless you pay me: I will pick you up --> you pay me (contra: you don't pay me --> I won't pick you up). Think about it. There are many other reasons why you cannot pick someone up at the airport.

If you pay me, I will certainly pick you up is the opposite: you make payment a sufficient condition.
You pay me --> I will pick you up

This is sorta of moot point, since the contrapositive of any conditional statement is logically equivalent to the conditional statement itself, you could say that any conditional relationship indicator shows each variable as both a sufficient and necessary condition of the other.

--LinkRemoved--

I think it's fruitful to learn the multiple ways of being able to diagram 'unless' statements, so that you can either use both or choose the one that's easiest for you.

[tomwatts]

I switched to teaching the "if not" way because teaching the other way was too hard and people screwed it up too much.

One thing that I find trips people up from time to time is that when the word "infer" appears in the answer choices, it usually means "draws as a conclusion." So if an answer choice says something like, the argument "infers a causal relationship when only correlation has been established," that means that the conclusion was that there was a causal relationship.

This is related to the issue that a lot of people confuse "infer" and "imply," which drives me nuts, because they're completely different words. If an argument implies something, it suggests it without directly saying it. If the argument infers something, that means it concludes something.