Realllllly struggled with any of variation of "only" statements until I realized that:
“The only” → sufficient
“Only / only if / only when” → necessary
“The only” singles out a group and says that all of them must satisfy some property. That’s the same pattern as “all” or “every.”
Examples:
The only students invited are seniors.
Translation: If you're invited, you're invited, you're a senior
Symbolize: Invited → Senior
The only animals in the room are cats.
Translation: Every animal in the room is a cat.
Symbolize: In room → Cat
The only oral myths that survived are the ones written down.
Translation: All the oral myths that survived were written down.
Symbolize: Survived → Written down
This concept really really frustrated me for a long time and made me feel like I was stupid!! I hope this can help anyone else going through something similar <3
The thing that has helped me the best is trying to think of these are the subset/superset and then build the Lawgic based off of that.
Another thing I keep in mind is the idea that, membership in the subset in necessary for membership in the superset, BUT membership in the superset is not sufficient for membership in the subset.
Translation: If I am inside my room, I am also inside of my house (If I am in the subset, I am also in the superset).
BUT if I am in my house that does not mean I am in my room (If I am in the superset, that does not mean I am in the subset, there maybe some other door I need to enter before I can be in the subset)
#feedback at the end of these lessons the instructor stresses the importance of understanding sufficiency and necessity instead of just relying on conditional indictators. Therefore, I think you should include an actual explaination of the answers in this video instead of just pointing out the conditional indictators as reason enough
finally got 5/5!! Glad I caught the context in #4 and didn't focus too much on indicators. I'm trying to make sure locating indicators in secondary to figuring out proper context of indicator words.
I really struggled with this one (got many wrong) any tips? They all seem so relative like either or clause could be sufficient or necessary... what am I missing?
What helped me surprisingly, was taking the contrapositive of the statement before I take the actual translation. For whatever reason, it helped me a lot to do that before working backwards to the actual translation.
So for example, for question 4, instead of immediately reasoning "oh, internally consistent scientific theory → plausible", I said: "Okay, after reading this statement, this means that if I don't have an internally consistent scientific theory, then it wouldn't be plausible. But, if it was an internally consistent scientific theory, then it would be! So that means that internally scientific theory goes first and then plausible goes next":
internally consistent scientific theory → plausible
Also, visually writing out the statement helped me a lot. Especially if I put a member in the subset to help solidify my understanding even more.
I hope this helps a little bit! It took me some time to understand the concept myself.
For me, depending on the statement, I find it easier not to think about which indicator word is being used, but instead I create the contrapositive statement and see if that makes sense.
For example, #3: lets say you flip the sufficient and necessary conditions on accident - highest flying bird → nests in the Andes, contrapositive being if does not nest in the andes → not the highest flying bird - I know this is incorrect because it assumes the highest flying bird ONLY nest in the Andes, which is not necessarily true based off the context given, so more logically it is nest in andes→highest flying bird
Quick tip: it always helps me so much to draw the subsets and supersets for each the questions! That way I can visualize what is being said and fully comprehend what the sentence means and why one things guarantees another, etc.
I literally got numbers 1, 3, 4, and 5 wrong because the I put the wrong concepts on the wrong side of the arrow. I do not understand what I am doing wrong...
The sufficient clause is introduced by the words if, when, where, the only, every, any, all.
The necessary clause is introduced by the words only, only if, only when, only where, always, and must.
We then put the respective clauses into place using this:
Sufficient --> Necessary
/necessary --> /sufficient
Example from above:
Only the highest flying birds of prey nest in the summits of the Andes.
"Only" introduces the sufficient clause since it's a sufficient condition indicator. So "highest flying birds of prey (hfbp)" is the sufficient clause and "nest in the summits of the Andes (nsoA)" in the necessary clause.
@Hnelson88 I was referring to "some people" all the extra words that are often used in the stimulus that are unnecessary and used to confuse people. I've been past this section so now much to contribute
@bangzoom9 Because it is a sufficient (but not necessary) condition for the number of beneficial soil bacteria increasing. The bacteria can increase in other ways.
However, because that is a necessary outcome of mixing plant material into garden soil, if it has not happened, then the plant material could not possibly have been mixed in.
I am genuinely so confused on how to know which side of the arrow the conditions go on. Full transparency I skipped much of the "foundations" curriculum but I had to come back to this part because I am so stuck when dealing with the logical reasoning questions. Please #help
I struggled with this this until someone pointed out the format for the "Lawgic" conditions was:
Sufficient --> Necessary
For example, #1 in this Skill Builder uses the conditional logic of:
Microscopic Organisms --> Must be capable of feeling pain
Being a microscopic organism is sufficient to be capable of feeling pain. However it is not necessary, as there could be other things like humans, or dogs, or cats, that are capable of feeling pain (though they are not included in this Question 1).
@DashiellBibler This was super helpful for me!! I used the examples of bears (bc I love them). I said the only bears in CA are black bears. This translates to bears in CA -> black bears. In other words being a bear in CA is sufficient to being a black bear, but not necessary. Black bears are also found in Alaska. I also tried this out with a necessary condition indicator: Only bears can make me want to run and hug them simultaneously. Translation: R and H -> B and the contrapositive is /B -> /R or /H. I think I'm going to go on the concept of bears and make examples for all the indicator words!!!
I dont know if this is helpful to anyone else but something that helps conditional logic make more intuitive sense to me is comparing the contrapositive i get from the initial statement. What I'm looking for is if I have confused the subset for the superset. It is something that has worked for me but Idk if its really helpful for anyone else or when it comes to more confusing sentences.
Question in the previous section: Only the highest flying birds of prey nest in the summits of the Andes.
Answer
nest in summits of the Andes → highest flying birds of prey
Question# 3 in this section:
The only oral myths that have survived are the ones that were eventually written down.
Answer
oral myth survived → eventually written down
in the question from previous section, the concept following "the only" is marked as the sufficiency and on the left side (unlike what we learned from the lessons)
however! In the question from this section, the connect following "the only" is marked as necessity and on the right side of the arrow.
I would love to know this as well. I am confused because sometimes we put the necessary condition on the left side of the lawgic statement, and other times on the right side...
I get your confusion since these indicators are so similar!
For the oral myths statement, the indicator is "the only" (Group 1). But for the high-flying birds of prey statement, the indicator is "only" (Group 2) - because it doesn't say "the only," it says "only the." Therefore, the oral myths statement had a Group 1 logical indicator, but the high-flying birds of prey statement is a Group 2 logical indicator, meaning that the concept right after is the necessary condition.
Hopefully that makes sense - they're very similar indicators, so whenever I see "only," I always take a minute to re-read the sentence and make sure I'm using the correct grouping.
in the previous section it says "the only" which indicates a sufficient condition - in this section it says "only the", which indicates a necessary condition. Hope this helps. He didn't clarify that "the only" indicated a sufficient condition but the comments in the last section did and that helped me figure it out lol
#2 I'm confused on why the answer is BERT -> BGBS. I thought "only if" is a necessary condition and makes it so that clause 2 goes first and then clause 1.
My answer was: BGBS -> BERT
My reasoning was that since the idea "good business sense" immediately follows the logical indicator "only if" it should go first.
That was my first thought as well, but this is my understanding of it...
I believe it is BERT → BGBS because "BGBS" follows the "only if". And the "only if" introduces the necessary condition. And the necessary condition has the arrow pointing to it (goes second). So if they are doing the environmentally right thing it must make good business sense.
"BGBS" → "BERT" would imply that in order for it to make good business sense the business must be doing the environmentally right thing, which I don't believe is what the statement is saying.
In this case the "BGBS" is the superset and therefore goes second; whereas "BERT" is the subset and goes first. So if a business is doing the environmentally right thing (subset), it must make good business sense (superset).
I found question 1 on the last skill builder "it's always sunny in Philadelphia" had a good and clear explanation of this.
I could be totally wrong but that's how I have been thinking of it!!
167 comments
Realllllly struggled with any of variation of "only" statements until I realized that:
“The only” → sufficient
“Only / only if / only when” → necessary
“The only” singles out a group and says that all of them must satisfy some property. That’s the same pattern as “all” or “every.”
Examples:
The only students invited are seniors.
Translation: If you're invited, you're invited, you're a senior
Symbolize: Invited → Senior
The only animals in the room are cats.
Translation: Every animal in the room is a cat.
Symbolize: In room → Cat
The only oral myths that survived are the ones written down.
Translation: All the oral myths that survived were written down.
Symbolize: Survived → Written down
This concept really really frustrated me for a long time and made me feel like I was stupid!! I hope this can help anyone else going through something similar <3
@cat13 THIS IS SO HELPFUL! THANK YOU!!
The thing that has helped me the best is trying to think of these are the subset/superset and then build the Lawgic based off of that.
Another thing I keep in mind is the idea that, membership in the subset in necessary for membership in the superset, BUT membership in the superset is not sufficient for membership in the subset.
Translation: If I am inside my room, I am also inside of my house (If I am in the subset, I am also in the superset).
BUT if I am in my house that does not mean I am in my room (If I am in the superset, that does not mean I am in the subset, there maybe some other door I need to enter before I can be in the subset)
Example of how I drew out the first 3 questions
#feedback at the end of these lessons the instructor stresses the importance of understanding sufficiency and necessity instead of just relying on conditional indictators. Therefore, I think you should include an actual explaination of the answers in this video instead of just pointing out the conditional indictators as reason enough
+1
Adding “the only” and “whenever” to sufficient indicators.
Reminder:
Group 1 Indicators indicate sufficient conditions
Ex: If, When, Where, All, Every, Any
Translation Rule: The idea immediately following the conditional indicator is the sufficient condition.
...whereas...
Group 2 Indicators indicate necessary conditons
Ex: Only, Only if, Only when, Only where, Always, Must
Translation Rule: The idea immediately following the logical indicator is the necessary condition
@lainlvrlauren is this the "equation"
Sufficient ---> Necessary
and then we plug in the concepts on either side of the arrow according to which indicator is used?
@Raisethescore yes!
my first 5/5, i used to pray for times like this
5/5 We getting there!!!!
I just have to remember what the indicator words are. If I have a list next to me, I always get it right.
test before this humbled me, finally clicking for me....for now
1/5. Losing my mind
finally got 5/5!! Glad I caught the context in #4 and didn't focus too much on indicators. I'm trying to make sure locating indicators in secondary to figuring out proper context of indicator words.
@DouglasNeumeyer yea I focused on the indicator and that caused me to go against what my internal logic was telling me to do ..
I really struggled with this one (got many wrong) any tips? They all seem so relative like either or clause could be sufficient or necessary... what am I missing?
What helped me surprisingly, was taking the contrapositive of the statement before I take the actual translation. For whatever reason, it helped me a lot to do that before working backwards to the actual translation.
So for example, for question 4, instead of immediately reasoning "oh, internally consistent scientific theory → plausible", I said: "Okay, after reading this statement, this means that if I don't have an internally consistent scientific theory, then it wouldn't be plausible. But, if it was an internally consistent scientific theory, then it would be! So that means that internally scientific theory goes first and then plausible goes next":
internally consistent scientific theory → plausible
Also, visually writing out the statement helped me a lot. Especially if I put a member in the subset to help solidify my understanding even more.
I hope this helps a little bit! It took me some time to understand the concept myself.
For me, depending on the statement, I find it easier not to think about which indicator word is being used, but instead I create the contrapositive statement and see if that makes sense.
For example, #3: lets say you flip the sufficient and necessary conditions on accident - highest flying bird → nests in the Andes, contrapositive being if does not nest in the andes → not the highest flying bird - I know this is incorrect because it assumes the highest flying bird ONLY nest in the Andes, which is not necessarily true based off the context given, so more logically it is nest in andes→highest flying bird
@katieghart01 thank you!
#feedback A written answer bank would be useful here so I don't need to watch the video to check each answer.
I made flash cards to help memorize group 1-4 conditional indicators, thought I’d share in case it would be helpful to anyone else. I’m redoing this course after getting through most of it and taking the lsat and not doing as well as I hoped. Looking back I realize how important it is to know these. https://quizlet.com/1153975729/lsat-7sage-conditional-indicators-to-share-flash-cards/?i=71yhg9&x=1jqY
@Elideebeep Thank you
@SilasMcIntire of course!
Quick tip: it always helps me so much to draw the subsets and supersets for each the questions! That way I can visualize what is being said and fully comprehend what the sentence means and why one things guarantees another, etc.
Gotta remember “only if” means “provided”
i don't have too much of a problem translating them, but I'm having a difficult time understanding what side goes on either arrow, can someone help
@NicoleSpradlin same, and it usually stems from questions including the word "only." this reddit thread really helped me!! https://www.reddit.com/r/LSAT/comments/16ckbih/the_only_vs_only/
I literally got numbers 1, 3, 4, and 5 wrong because the I put the wrong concepts on the wrong side of the arrow. I do not understand what I am doing wrong...
My understanding is this:
The sufficient clause is introduced by the words if, when, where, the only, every, any, all.
The necessary clause is introduced by the words only, only if, only when, only where, always, and must.
We then put the respective clauses into place using this:
Sufficient --> Necessary
/necessary --> /sufficient
Example from above:
Only the highest flying birds of prey nest in the summits of the Andes.
"Only" introduces the sufficient clause since it's a sufficient condition indicator. So "highest flying birds of prey (hfbp)" is the sufficient clause and "nest in the summits of the Andes (nsoA)" in the necessary clause.
Written in lawgic, it looks something like this:
hfbp --> nsoA
/nsoA --> /hfbp
Hope this helps!
the wording on number four was fucking me up, but after eliminating the word salad, it made it easier
@DezerreeSnyder
Where did you see the word ‘salad’?
@Hnelson88 I was referring to "some people" all the extra words that are often used in the stimulus that are unnecessary and used to confuse people. I've been past this section so now much to contribute
Question 5 is confusing for me. Why plant material mixed into garden soil comes first, not the bacteria?
@bangzoom9 Because it is a sufficient (but not necessary) condition for the number of beneficial soil bacteria increasing. The bacteria can increase in other ways.
However, because that is a necessary outcome of mixing plant material into garden soil, if it has not happened, then the plant material could not possibly have been mixed in.
I am genuinely so confused on how to know which side of the arrow the conditions go on. Full transparency I skipped much of the "foundations" curriculum but I had to come back to this part because I am so stuck when dealing with the logical reasoning questions. Please #help
@Nickgigs Hey Nick!
I struggled with this this until someone pointed out the format for the "Lawgic" conditions was:
Sufficient --> Necessary
For example, #1 in this Skill Builder uses the conditional logic of:
Microscopic Organisms --> Must be capable of feeling pain
Being a microscopic organism is sufficient to be capable of feeling pain. However it is not necessary, as there could be other things like humans, or dogs, or cats, that are capable of feeling pain (though they are not included in this Question 1).
@DashiellBibler THANK YOU!
@DashiellBibler This was super helpful for me!! I used the examples of bears (bc I love them). I said the only bears in CA are black bears. This translates to bears in CA -> black bears. In other words being a bear in CA is sufficient to being a black bear, but not necessary. Black bears are also found in Alaska. I also tried this out with a necessary condition indicator: Only bears can make me want to run and hug them simultaneously. Translation: R and H -> B and the contrapositive is /B -> /R or /H. I think I'm going to go on the concept of bears and make examples for all the indicator words!!!
I dont know if this is helpful to anyone else but something that helps conditional logic make more intuitive sense to me is comparing the contrapositive i get from the initial statement. What I'm looking for is if I have confused the subset for the superset. It is something that has worked for me but Idk if its really helpful for anyone else or when it comes to more confusing sentences.
Question in the previous section: Only the highest flying birds of prey nest in the summits of the Andes.
Answer
nest in summits of the Andes → highest flying birds of prey
Question# 3 in this section:
The only oral myths that have survived are the ones that were eventually written down.
Answer
oral myth survived → eventually written down
in the question from previous section, the concept following "the only" is marked as the sufficiency and on the left side (unlike what we learned from the lessons)
however! In the question from this section, the connect following "the only" is marked as necessity and on the right side of the arrow.
I'd appreciate some clarification!!
I would love to know this as well. I am confused because sometimes we put the necessary condition on the left side of the lawgic statement, and other times on the right side...
Like #3 and #4
I get your confusion since these indicators are so similar!
For the oral myths statement, the indicator is "the only" (Group 1). But for the high-flying birds of prey statement, the indicator is "only" (Group 2) - because it doesn't say "the only," it says "only the." Therefore, the oral myths statement had a Group 1 logical indicator, but the high-flying birds of prey statement is a Group 2 logical indicator, meaning that the concept right after is the necessary condition.
Hopefully that makes sense - they're very similar indicators, so whenever I see "only," I always take a minute to re-read the sentence and make sure I'm using the correct grouping.
in the previous section it says "the only" which indicates a sufficient condition - in this section it says "only the", which indicates a necessary condition. Hope this helps. He didn't clarify that "the only" indicated a sufficient condition but the comments in the last section did and that helped me figure it out lol
#2 I'm confused on why the answer is BERT -> BGBS. I thought "only if" is a necessary condition and makes it so that clause 2 goes first and then clause 1.
My answer was: BGBS -> BERT
My reasoning was that since the idea "good business sense" immediately follows the logical indicator "only if" it should go first.
That was my first thought as well, but this is my understanding of it...
I believe it is BERT → BGBS because "BGBS" follows the "only if". And the "only if" introduces the necessary condition. And the necessary condition has the arrow pointing to it (goes second). So if they are doing the environmentally right thing it must make good business sense.
"BGBS" → "BERT" would imply that in order for it to make good business sense the business must be doing the environmentally right thing, which I don't believe is what the statement is saying.
In this case the "BGBS" is the superset and therefore goes second; whereas "BERT" is the subset and goes first. So if a business is doing the environmentally right thing (subset), it must make good business sense (superset).
I found question 1 on the last skill builder "it's always sunny in Philadelphia" had a good and clear explanation of this.
I could be totally wrong but that's how I have been thinking of it!!
4/5. I messed up on q3