Understanding LSAT Logic

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The second lesson of the FREE LSAT prep course offered by Insight LSAT. This is a comprehensive course for LSAT preparation, taught by an instructor who scored 179 on the LSAT. We go through every section, providing expert advice, strategies, illustrations of methods, and more!
In this lesson, we discuss fundamental logic skills that will be useful on all sections of the LSAT.
Topics include:
- logical consequence
- logical sequence vs. textual sequence
- the "so" test
- intermediate conclusions
- necessary and sufficient assumptions (conditionals)
- negation
- numerical words and phrases
- symbolic logic
- contrapositives

[@babuton]

the "so" test has busted this shit open for me. thanks!

[@aracelianaya7832]

Right!! that made all the difference.

[@lolo2good]

Thank you Lord for the other side of KZbin …I no longer watch music videos, I must study for the LSAT! This guy is awesome! 🎉2024🎉

[@laurynfarley]

i’m right with you ! we got this

[@lolo2good]

@@laurynfarleywe will be lawyers 🎉 GOOD LUCK!!!

[@peacesoundsstuff]

All Aboard, I had to physically get myself to change the habit Let’s crush this test!!!!

[@samuelgyan1730]

Let do it guys and make him proud

[@robertsloan3272]

How could anyone dislike this video? It truly lays the foundation for development and improvement in all 3 subjects. Albert is an incredible teacher! Thank you for sharing your knowledge and posting this lesson.

[@laurasolomon1522]

Have you written your LSAT and how was it ?

[@parzer0]

For me it was his voice. Your comment made me click the dislike button because its very obvious not a presidential or militant voice but one of a kid learning through teaching using his shy microphone skills. I'm sure you aced the logical reasoning.

[@damndragonflies]

@@parzer0 for me.. That’s exactly WHY I am sticking around for the next… I love his delivery!! I’m sure if a militant person was explaining all these symbols I might not understand so easily. He doesn’t assume you know anything.

[@walabang437]

​@@parzer0you posh bimbo

[@SenseiLlama]

the people who disliked it sold competing courses. Then got outdone, for free.

[@GoodNews-px2im]

The “so rule” is golden! I’ve always been taught that whenever there is a “therefore” find out what it’s there for (finding premises that support or lead to the conclusion).

[@scherretzfamily7196]

I made a 144 the first time I took the LSAT just by watching the first couple of these videos. and that is after a trip to Vegas. I made a 136 after paying 1800 for one of those supposed prep courses.... which goes to show you the difference

[@06amaris]

You are awesome..thank you so much for this. I have been procrastinating taking the LSAT for many many many years...i am now 40 yrs old and fully committed/motivated to reach my goals. Thank for helping with this journey!!

[@MsBdoll87]

thanks for sharing. i am 34 and have been the same way...procrastinating. what's the latest on your journey?

[@vehement-critic_q8957]

​​@@MsBdoll87 I'm 30 here & an ESL that means I'm second speaker of English, so it's a little burdensome as language could be a barrier, but that tutor knows how to guide & show the way to success. & yeah, I'm just like you procrastinating due to circumstances out of my hands.

[@LoveLifeAllWays]

Wow! I'm at the age now and I'm considering law school. I should have attended right after graduating. Did you attend law school!? If so how is it going?!

[@coltonstogner4363]

Wow youre amazing at explaining these complex logical relationships in a way that anyone can pick up on. Thank you for taking the time to create these videos and making this available for free

[@chelseaamira6894]

This video has helped me soooooo much. You can't even begin to understand! This is what everyone should watch before even studying anything for the LSAT. Your teaching style makes it so easy to pay attention to,and understand what I'm learning, thus keeping me fully engaged the whole entire time. Thank you so much I cannot wait to watch the rest.

[@NoeItorious]

This was really fun. Nailed it too. Thanks!

[@KnockOutCutie]

I really enjoyed this lesson your teaching style fits my learning style I’d pay for a whole course

[@ttothemfd]

This is fantastic. Thank you so much! Understanding these symbols and their application is going to help me exponentially

[@ginikaurpropertiesgroup7840]

I love it! Thank you for all the great exercises and help!

[@kristal0076]

Hi, I scored 162 on practice test but want to do better. this vid is awesome to get my my crazy thoughts logical!

[@withlovestephaniedenise7024]

I was told about the LSAT from a lawyer, who told me it'd needed for law school. Soooo, I tried it without knowledge. I was lost. Then I found this video. Wow! I went back to the test, and although, its approach is new to me, I had a better understanding. Thank you,

[@JacksonDahlen107]

Working through these over the next week. Bless your soul.

[@millicentpepion]

OMG.. I"m so excited!! Thank you for putting this together!!

[@toksfashable]

Amazing lesson, thank you for taking the time to explain all these to us. I really learnt a lot!

[@syedmammar1]

Learned a great deal. Thank you.

[@laminar28]

These videos are excellent, and I suggest anyone looking to raise some points go through the entire lesson plan!

[@SingingDiaries]

This was so so helpful! Thank you for uploading this :D

[@amynguyen6411]

Thank you for making such a great video!

[@LanaIrsh]

I took a diagnostic test before watching this video and was tripping up on some logic games questions because I was spending too much time rereading the conditions and scenario, your methods have helped me so much and made me realize the amount of time I could have saved when doing those logic games.

[@anthax1]

my first time trying these out, seems complicated but pretty straight forward with some practice.

[@davidndoma9286]

I feel pumped after watching this video. Thank you for such a great video.

[@quitamartor4314]

WOW, thank you so much for these lessons; I've a LSAT to write on Monday July 4. Very sure this would help me 🙏

[@hailskay]

how did it go??

[@carolinan4768]

Love the way you teach! Thank you very much! Love this!

[@uchechigenevieve7324]

I have watched a lot of videos, yours is the only one so far that explained thing in a very clear and understandable way.

[@lolo2good]

Very true! I took a course in college, but all they did was send me some practice books that made no sense until I started watching these videos, but now I will understand my PrepTest books a lot better!

[@lolo2good]

Same!!!!

[@ceciliaaceves6397]

Amazing Stuff! It has helped me so much!

[@andrerobinson2923]

I finally caught on and was able to understand it as he went on. I got the majority of them correct. Thank you for explaining it the way you did.

[@chrisbrodie5650]

Thank you for putting this program together. Helps me study the LSAT. I work full time and I hope this works for high scores!!!

[@johngivens5004]

Great video got me thinking logically now I'm a keep working at it everyday from now on

[@criminalscum8472]

John Givens You can start by practicing basic English grammar.

[@nufirmdm]

@@criminalscum8472 shut the fuck up

[@Pegalomania]

Very helpful & kind, thank you.

[@ikarhbzgahk276]

I took a logic course a couple years ago so this all makes sense to me

[@amoontree]

Lol

[@itswolvesgate]

Best LSAT video I have seen so far thanks 👍👍👍

[@ScottWitoff-hv1qx]

Every lesson Insight LSAT teaches is excellent. I'm watching one of those lessons. I can conclude that I am watching an excellent lesson. 🙂

[@sadeekwalker6355]

Amazing videos.

[@ymerithebeloved]

this is really helpful and i really like the way you teach. thank you so much!

[@alyssa01825]

Taking the LSAT this summer, thanks for your course

[@elle9633]

Excellent! Thank you!

[@Duckgoose17]

Wow I am actually understanding and getting this...Exciting....ty for sharing

[@petercho7660]

Hi! Thanks for the video. In the example "If many people attend the party, we will need to hire a server", you said the negation is "If we don't need to hire a server, then ..." I was wondering what the implication of "if we don't need to hire a server" is. Does that mean we don't hire any servers, or does it mean that you don't hire A server (either no servers or many servers)?

[@christiancabrera4708]

Amazing

[@ruthiyarana9130]

Thank you so much bro

[@shrinidhiharwadekar2706]

i was so scared for the LSAT exam. Thank you so much sir, this video has made me very easy to study now.

[@damndragonflies]

Thank you…. not sure yet how it applies to the LSAT!! But I appreciate this before I pay for my tutor and take any practice exams!!

[@alesanchez8492]

this channel is a gem

[@allissberry6959]

These videos are very helpful and study tips to help prepare me for the LSAT test. I plan to take it either this year or next year for sure, I hope I do a good job.

[@LucianaFerreiraHervey]

Thanks! Your videos are great!!!

[@insightlsat]

Thank you too!

[@theelizabethanway]

The Tom example...heartbroken Tom..Tom Petty and the Heartbreakers. And LuluLemon....love the puns

[@cryptocanada3038]

oh wow! I didn't even pick that up. Great eye!

[@chrisgreen1579]

Great resource so far

[@PengNation]

Great video. Watching this after I took a cold diagnostic test and I can see how much of the symbolic representations especially might have been useful during the test. A suggestion: on the slide on numerical proportions, it might be more accurate/clearer to say 50%< than 51%+ etc.

[@uria702]

I agree. Change it to >= or

[@hard2getitrightagain314]

This is an important point. There is a lot of territory between 51% and 49%. 50% + 1 is one way I was taught. Even that is too broad. >50% is the most correct, I imagine.

[@mazinsyed7279]

so when writing counter positives you always have to negate the conjunctions and the disconjunctions from both sides in all cases? correct

[@lucivaniapereira5936]

When can I find more exercises like this one ? I am having trouble negating.

[@aminaaftab1811]

amazing thank you

[@imranhowcani1981]

you just made the introduction easy

[@hhhpestock951]

In response to the negation of "If you prepare for the LSAT, you will do well... ", instead of filling in random bubbles and doing well, it might just make perfect sense to you.

[@Rm9512]

i have a question: in the practice section at the end of the video, in the symbolic logic of "if nobody helps, i will quit..." shouldn't the symbol for help be positive? without the negation symbol? idkw i'm not getting that. would really love to know what i misunderstood!

[@Applecompuser]

There was reference to a free worksheet on the website, however, I do not see it. Does anyone know where this worksheet is? PS This is a great video series! Thanks for sharing them. PSS If anyone else is prepping for the LSAT now, I would be happy to do a study group even if by Facetime etc.

[@About_Argo]

I know it's late, I hope this is the correct one. www.insightlsat.com/worksheet

[@cryptocanada3038]

I can't believe how much I love this shit!

[@deepthroat533]

Falsifying numerical statements - "a few sandwiches remain." A few may refer to 2+ but it also implies a limit, not many therefore we can say 0 -1 sandwiches or there is an abundance (non-countable but in excessive of a few)

[@IsaacWMayer]

You’re my hero! 💯

[@AuzSanchez]

1:11:55 can you explain why you wouldn't negate H in the last question in the initial answer? I negated it because of the word "nobody" and then in the contrapositive there was no negation for H. I hope this makes sense!

[@higherlight9668]

thanks for the vid i like it i will get THAT LSAT WOOOO

[@kifeda]

I'm struggling but this is a really good video. Like excellent.

[@willonz]

@35:11 water can boil if pressure is low enough, too. Does this example assume this as well?

[@dirty_candy]

On the Tom and Erica one. I got "the assumption is that he WILL," when nothing says a plan is the same as execution. Is that the same as saying what you said, that she never said no, because nothing said he never asked her?

[@dirty_candy]

In the symbols part, you treat "plans to" as "will." How is that going to help?

[@bradcooke5383]

Good video for LSAT prep. At 58:06 there's a false statement. Echidnas and the duck billed platypus are both mammals and both lay eggs.

[@psykored524]

@59:13 when I read that sentence I right away thought of Pink Floyd haha

[@kjaniece]

I had a question about the falsifying numerical statements. On the most of the questions, is it possible to say all or because “all” was not used in the PowerPoint prior, it can not be used as an answer? Ex- some children dance translates to “it’s not the case that some children dance. The only answer that was given was 0-1 children dance. Can “all”also be used?

[@BoulderBoulder_]

I should've watched these videos while I was taking symbolic logic lol. Also, can confirm, symbolic logic was way harder than the material I've seen on the LSAT so far haha

[@napnap609]

In the example of conditionals with "only", I get the first statement "I will attend ONLY if I can afford it, to which you offer a counter thought of: You may not go even if you CAN afford it. Great I get that. But in the boiling water example you don't offer a counter thought. Is there one? "Only if enough heat is applied to it does water boil". So that's definitely a necessary condition, but how is that not sufficient?

[@nicolemarini7540]

question: at 19:22, the exercise with Erica and Tom. Could the intermediate conclusion be: Erica will say no, excluding ?

[@joshuarizek9043]

thats exactly what bothered me about this. to say "she will definitely say no" and " she will say no tomorrow" are very close to the same thing. I don't see why that intermediate conclusion is necessary.

[@insightlsat]

The argument is all about what's going to happen tomorrow, so we have to keep that in there.

[@cecilialaracengiz2848]

Hi, on the practice problems, the one that says "if nobody helps, I am going to quit" you started with H--> Q shouldn't it be a negated -H first since its nobody helps and the negated version would be somebody helped.

[@cecilialaracengiz2848]

I really like your videos by the way. They are very helpful.

[@ohandromeda6995]

At 1:12:00 would writing the symbols (neg)H ---> Q, with the second being (neg)Q ---> H be correct? When speaking out loud I read as If I don't quit, at least one person helped.

[@AlexanderMahone-sp3zh]

OMG, this is gold

[@lordvader5246]

I have a question regarding the conditional "only" example of: "only if enough heat is applied to it does water boil." This might be a matter of interpretation but when I read "enough heat" im assuming its suggesting that there is "enough heat to get water to boil" in which case applying "enough heat" to water to get it to boil would make it both necessary and sufficient to get water to boil which would make it an "if and only if" statement as opposed to an "only" statement. Can someone explain why I am wrong or if I just interpreting this differently? He didnt spend a lot of time answering that example.

[@TheMangoer]

I am confused about this too, does anyone have an explanation?

[@samnunn3948]

Would the contrapositive of the Sam Bart Alex portion be; If not Bart ^(and) Alex -> not Walking -> not enough Time v(or) not Sam. ??? Edit: If not B ^ A > not W > not T v S

[@chelorecords8483]

what do we do about nor, or neither

[@jayl2331]

“So test” Very nice!

[@fancydiamondllc4256]

Very good practice

[@hhhpestock951]

I went for NotP instead of C because in this scenario the parade (P) would not have happened if it had rained (R)

[@simsimmons8884]

Question. At 9:34 you present the "so test" on the paragraph regarding taking the LSATs. I see another conclusion as "so, practicing LSAT questions is an effective way of improving your LSAT score." Why is this not the conclusion? This seems as logical as "so, time spent practicing LSAT questions is thus time well spent." It seems that the only indicator to pick one over the other is that " time spent practicing LSAT questions is thus time well spent." is a more general conclusion. Is this test something that should be added to the final determination of which conclusion is the final conclusion? The more general the conclusion, the more final it is.

[@maleekielshamsa513]

1:06:00 Please advise Why is it not Jan or Kyle instead of Jan and Kyle? Since it was originally a disjunction??

[@iStorm-my5fp]

Thank you

[@troymcdougal9010]

You said "Most" and (assumedly) "The majority of" can be 100% of the items, but can "a minority of" be 0% or does it have to be at least 1 of the item?

[@ruqaia9563]

for the Q (if nobody helps, I am going to quit) I wrote it as (no H > Q) then the opposite ( 1+ Q > H) meaning I interpret no bady helps as a negative scenario. I'm not sure if it's only another way or it going to affect the result in more complicated situations

[@treynoe4934]

In the conditionals sections can someone explain what he means by Sufficient and Necessary conditions? I understand necessary, but the definition of sufficient was muddied by the "if and only if" conditionals

[@abracadabra2395]

Questions: 1. Isn't the missing piece the assumption that Tom will ask her out, not that she will say no if he does? The former isn't explicitly stated, while the latter is. 2. The Lu sisters could own a lemon tree and the entire argument could be junk. This feels like a more blatant missing logic leap than the one you pointed out with Tom's broken heart. What am I not understanding? (Also, thank you for these videos!!)

[@politico6792]

Abra Morgan I’m no expert, but the concepts of symbolic logic don’t pick up these nuances of language. You treat every statement as a truth

[@hylandbenjamin12]

Thanks!

[@jonawells8064]

Can you explain why these are the conclusions? The LSAT question I didn’t understand why exactly it was “Time spent practicing LSAT questions is this time well spent”

[@austinallen5907]

Question, I know this is in 2017 so does the LSAT update to new terminology and terms or is the structure the same today?

[@chora5208]

Hey Austin, I am currently trying to figure out if I should self-study or buy an LSAT course but from what I know the structure is still pretty much the same today. When do you plan on taking the LSAT?

[@austinallen5907]

@@chora5208 Ok thank you for that information. Hoping to take it in the fall. Do you recommend any good prep books or anything?

[@chora5208]

Austin Allen yes I actually got the LSAT TRAINER OFF of amazon and I am starting a study session Sunday with a group of people I met on a zoom for a LSATPREP COURSE

[@kivigray0423]

28:17 Doesn’t it also leave open the possibility that no children play-as in 0-50% of children play? As opposed to just 1-50%?

[@insightlsat]

Yep 👍

[@geetar16]

Question.. For "If nobody helps, I am going to quit." Why is "nobody helps" represented by 'H' rather than negated 'H'? (¬H)

[@geetar16]

When we symbolized "If you don't eat your meat" we used negation '¬M' I'm wondering what the difference is between "didn't eat meat" and "nobody helped"

[@zachsabe]

@@geetar16good question i was wondering the same. maybe he sees it not as a negation but as "0 helpers" and that in itself is not a negation?

[@donnakim6208]

Because if you use "not H" for nobody helps, in the negation, it becomes "Q -> H" which means if I quit - help. This might lead to the extreme since "helps" can mean at least one person helps, many people help or all help. However if you just take some extra trouble to say in your head that H stands for "nobody helps," the negation of "H->Q" will be '"not Q -> not H" meaning If I am not quitting, it is not that nobody helped = If I am not quitting at least one person helped.

[@phareke]

I have a question. If at 1:13:29 we can start with "if no D then R" the way we did, then why didn't we write the previous exercise at 1:11:36 the same way (If nobody helps then I quit)?

[@StoryBookMaker]

I have the same question as well. I had written for the contrapositive, that “if I did not quit, someone helped.” And I didn’t put a negation on the “H”

[@user-hj2ge8ph7q]

Another LSAT video said "some" means an unknown amount but yours says 2+. Which is correct?

[@prettynestd]

Very good

[@ScienceTheoryOfficial]

So helpful

[@larkinvarful]

Where can I find the practice exams?

[@fritzkreig1314]

i wrote it as not snowing p or m not at l is that the same as no p or m if no snow?