on this one wouldn't it be easier to just use intuition than to reason... it would take me well over 5 minutes to figure out the conditional diagramming whereas the answer is pretty obvious if I just look at the stimulus. I guess if I do that too much, my "common sense" could fail me and I'd end up falling for a trap.
He read my mind...I diagrammed pet stores...shameful, I know.
INSTEAD, kick things up the domain. We know from reading the rest of the stimulus, that it is only talking about pet stores in West Calverton so we can momentarily ignore that and go straight into the other conditions!
This does not make sense because Group Four Conditional means that you negate either and make necessary, in the case of the exampe he did the necessary part correct, but since there is a no in the beginning of of ansswer d. there should be a / before Indy. So therefore,
I actually found it "easier" and faster to do when I represented all of these as sets within sets (venn diagrams). Once I had the visual, it was straightforward to eliminate the answers that did not make sense and I was left with D, which was the only one I couldn't refute. It still took me more than the allotted 1-1.5mins, but if I did it the 7sage way (and was good at it), it would take me at least 5 minutes.
@mh12 I also did a venn diagram! His explanation wasn't helpful for this problem. With the my diagram, I see that if the pet store doesn't sell gerbils it must sell tropical fish and exotic birds; making D true. Got the right answer, but hope I didn't arrive there using the wrong method.
The main thing that keeps popping into my head, is how in the world am I supposed to process/chain/get the correct answer in just over a minute? I am completely overwhelmed I am not going to lie.
I was able to diagram the question properly but still had difficulty translating it into the correct answer. I did all the diagramming correctly but still picked the wrong answer.
I actually got hope for the LSAT solving this problem, though it took me forever. Despite the complicated diagramming, once I got it the answer was crystal clear. I really am sure that there is no impossible LSAT problem. Practice makes perfect I guess!!
Took me a minute to realize that first sentence is not useful other than to mentally dump things into domain and forget. Once you realize the most before most means nothing, the independently owned portion of the stim pops out and the logic falls into place. And the answer is right there in the ACs.
Curious to see how the intuition develops over time! This takes forever.
I have a question on conjunction and disjunction. I understand how the stim had a conjunction (fish and birds), but I seem to be confusing how the answer D became a disjunction (/fish OR bird). I understand the negation parts of it all, just a little confused why or how do you know D is a disjunction. indy -> /fish OR bird.
@MLugo1998 Right below Lesson 5 - West Calverton Pet Shops, it says "show question". You can use that to view the questions before he works through them on any of the videos.
I'm at a point in my studying where the logic here I completely understand, but the idea of working through a question like this in under 90 seconds feels impossible
@HenryLehmann I'm starting to realize we're going to have be able to do this intuitively in the end. There won't be enough time to diagram the stim and the answer choices.
@Bgsolo "but" operates exactly the same as "and" in logic. The only difference is rhetoric, because it implies a contrast between the two proposition. So the difference is stop thinking about a difference between "and" and "but" in logic! If you see "but" think "that means AND". "Or", on the other hand, is a very different logical operator. "Or" between two propositions (A or B) usually means either A is true and B is false, A is false and B is true, or A and B are both true. This is the inclusive or. You do have to pay attention to the grammar, though, because there are some specific places where "or" means ONLY ONE of A and B can be true, but the passage will make that clear if you pay attention to it. There is a final rare case where "or" in natural language actually means "and", which is when it's part of a comparative claim. If you say A is better than B or C, it actually means two distinct claims: A is better than B and A is better than C.
From the last sentence, I translated it to: (fish, no bird) → gerbils. Thus, in my head, the contrapositive was /gerbils → /(fish, no bird). Through that logic, I picked D. However, I wonder if that logic is flawed because I didn't even think of the and/or rules.
@MuskanKaur I mapped it out with the Venn diagram version and wrote out the conclusions I came to from my picture. I was able to get the correct answer before watching the video.
I couldn't wrap my mind around the logic but the visual nature of the Venn diagram helped a lot more.
if pet store /sell birds and sells fish, it must sell gerbils
But as we know, no stores sell gerbils in the city.
Now, AC D states that no independently owned pet store in West Calverton sells tropical fish but not exotic birds.
If we look at line two, we can see that all West Calverton stores that don't sell birds but do sell fish will sell gerbils. If the conclusion states that nobody in the town sells gerbils, that must mean that nobody meets the conditions for it, which is selling fish but not birds.
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247 comments
I hated this question so much but it makes more sense now.
The explanation was not helpful at all
I have to go restudy the Indicator groups 🥲
You don't even need to map this out. Just use your short term working memory and read the AC.
on this one wouldn't it be easier to just use intuition than to reason... it would take me well over 5 minutes to figure out the conditional diagramming whereas the answer is pretty obvious if I just look at the stimulus. I guess if I do that too much, my "common sense" could fail me and I'd end up falling for a trap.
He read my mind...I diagrammed pet stores...shameful, I know.
INSTEAD, kick things up the domain. We know from reading the rest of the stimulus, that it is only talking about pet stores in West Calverton so we can momentarily ignore that and go straight into the other conditions!
damn he clocked how i sped into mapping it
ended up with D using POE but FINALLY understood it when i reread the stimulus
This does not make sense because Group Four Conditional means that you negate either and make necessary, in the case of the exampe he did the necessary part correct, but since there is a no in the beginning of of ansswer d. there should be a / before Indy. So therefore,
/Indy--->/Fish or Bird
I actually found it "easier" and faster to do when I represented all of these as sets within sets (venn diagrams). Once I had the visual, it was straightforward to eliminate the answers that did not make sense and I was left with D, which was the only one I couldn't refute. It still took me more than the allotted 1-1.5mins, but if I did it the 7sage way (and was good at it), it would take me at least 5 minutes.
@mh12 I also did a venn diagram! His explanation wasn't helpful for this problem. With the my diagram, I see that if the pet store doesn't sell gerbils it must sell tropical fish and exotic birds; making D true. Got the right answer, but hope I didn't arrive there using the wrong method.
The main thing that keeps popping into my head, is how in the world am I supposed to process/chain/get the correct answer in just over a minute? I am completely overwhelmed I am not going to lie.
@Kjbrock I totally understand you! I honestly feel with practice and persevering we can get through this!
I was able to diagram the question properly but still had difficulty translating it into the correct answer. I did all the diagramming correctly but still picked the wrong answer.
Does anyone have any suggestions for this??
I actually got hope for the LSAT solving this problem, though it took me forever. Despite the complicated diagramming, once I got it the answer was crystal clear. I really am sure that there is no impossible LSAT problem. Practice makes perfect I guess!!
You could not have explained this in a more difficult way to understand. Do better.
@JacksonStephens That was their goal.
This is insane. I like to go through the the question before I watched the video.
I had to diagram this to even understand the stimulus. It then took me about 10 minutes to get to the answer. I got it right but wow
Why wouldn't most pet stores sell exotic birds and most stores that sell birds sell tropical fish translate to some pet stores sell tropical fish?
1) P -m-> EB -m-> TF
2) TF and /EB -> G [original]
/G -> /TF or EB [contrapositive]
3) IOP -> /G
IOP -> /G -> /TF or EB [linked]
Took me a minute to realize that first sentence is not useful other than to mentally dump things into domain and forget. Once you realize the most before most means nothing, the independently owned portion of the stim pops out and the logic falls into place. And the answer is right there in the ACs.
Curious to see how the intuition develops over time! This takes forever.
I have a question on conjunction and disjunction. I understand how the stim had a conjunction (fish and birds), but I seem to be confusing how the answer D became a disjunction (/fish OR bird). I understand the negation parts of it all, just a little confused why or how do you know D is a disjunction. indy -> /fish OR bird.
@gray
It's De Morgan's Laws!
(D) No independently owned pet store in West Calverton sells tropical fish but not exotic birds.
=
fish and /bird -> /indy
=
indy -> /fish or bird (De Morgan's Laws - change 'and' to 'or' , and negate each elements)
Hope this helped you! :)
[This comment was deleted.]
@MLugo1998 Right below Lesson 5 - West Calverton Pet Shops, it says "show question". You can use that to view the questions before he works through them on any of the videos.
I'm at a point in my studying where the logic here I completely understand, but the idea of working through a question like this in under 90 seconds feels impossible
@HenryLehmann I'm starting to realize we're going to have be able to do this intuitively in the end. There won't be enough time to diagram the stim and the answer choices.
@HenryLehmann Someone I know who took the LSAT said you earn doing it fast and intuitively by lots of diagramming practice which stuck with me.
Can someone help me determine when "but" because "and" vs "or?"
@Bgsolo "but" operates exactly the same as "and" in logic. The only difference is rhetoric, because it implies a contrast between the two proposition. So the difference is stop thinking about a difference between "and" and "but" in logic! If you see "but" think "that means AND". "Or", on the other hand, is a very different logical operator. "Or" between two propositions (A or B) usually means either A is true and B is false, A is false and B is true, or A and B are both true. This is the inclusive or. You do have to pay attention to the grammar, though, because there are some specific places where "or" means ONLY ONE of A and B can be true, but the passage will make that clear if you pay attention to it. There is a final rare case where "or" in natural language actually means "and", which is when it's part of a comparative claim. If you say A is better than B or C, it actually means two distinct claims: A is better than B and A is better than C.
@dh2303 Thank you!! Very helpful!!
From the last sentence, I translated it to: (fish, no bird) → gerbils. Thus, in my head, the contrapositive was /gerbils → /(fish, no bird). Through that logic, I picked D. However, I wonder if that logic is flawed because I didn't even think of the and/or rules.
Hi, does anyone have an easier approach? Im a bit confused
@MuskanKaur I mapped it out with the Venn diagram version and wrote out the conclusions I came to from my picture. I was able to get the correct answer before watching the video.
I couldn't wrap my mind around the logic but the visual nature of the Venn diagram helped a lot more.
@rjon27 Can you show this, please?
@MuskanKaur For me i did
Pet stores M Sells birds M Sells Fish
if pet store /sell birds and sells fish, it must sell gerbils
But as we know, no stores sell gerbils in the city.
Now, AC D states that no independently owned pet store in West Calverton sells tropical fish but not exotic birds.
If we look at line two, we can see that all West Calverton stores that don't sell birds but do sell fish will sell gerbils. If the conclusion states that nobody in the town sells gerbils, that must mean that nobody meets the conditions for it, which is selling fish but not birds.