@naomiy2k I feel the same way, but honestly, as you move forward I feel like the information starts to subconsciously make sense and you start to apply what you've learnt without necessarily digging deep into the trenches of you brain lol
@naomiy2k To my understanding the kick it up method is not something you need to use when evaluating a conditional claim, but is an option that makes it easier. At the moment I generally have not been thinking about it in drills but I think I eventually will when I train harder levels.
For those confused about uni-conditionals vs. bi-conditionals, consider these:
Uni-conditional example: "You will receive a medal if you finish the race in first-place."
We can logically create this diagram: finish race in first-place → receive a medal
Steve received a medal. Can we logically conclude that he therefore finished in first-place? No! The rule only tells us what happens if people finish first-place. Perhaps people who finished second and third also received a medal. Maybe every race participant received a medal! Who knows?
This makes so much more sense - and a good way to think about it in this example is if is a sufficient indicator and only if is a necessary indicator thus its both necessary and sufficient
Oh yeah, this is when the fun begins. Only thing you can do is to keep pressing forward. Sometimes you have to mess up applying these concepts in order for them to click. Don't get stuck here, keep going and keep failing: that's how you learn!! Don't give up :D
Is it the case for anyone else that you understand how to work out these scenarios in English, but the Lawgic translation then makes it confusing to understand?
yes! i'm understanding it perfectly when it's in english but the second they bring out lawgic and conditionals and other nonsense, i get so confused. making me wonder if this is necesary for me to understand for the LSAT
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Wednesday, Jul 30, 2025
@partenr Apparently you need this stuff for complex problems, right? Because I agree with you that it makes sense in English then mathy logic makes it confusing, seems like I am tripping myself up on purpose.
You commented months ago, what did you find out knowing what you know now?
In my opinion the best way to explain/understand a bi-conditional claim is how it is taught in Math. It is taught as an 'iff' claim aka. an if and only if claim.
All an iff claim means is that each element implies the other:
Iff A then B, means: A --> B, and B --> A.
It is helpful to differentiate an iff claim from a regular conditional because of LSAT questions as so:
an animal is a zebra if and only if it has white and black stripes. (our biconditional claim in an argument on the LSAT)
Jerry is an animal that has black and white stripes. (an assertion made as part of the argument)
What inference can you make? (LR question on LSAT)
That Jerry is a zebra. (Answer derived by understanding that it is an iff claim, so both elements imply each other)
@dylancameron814 didn’t even look at the lesson and it clicked because of your comment.
Wish they would have used this example:
Student are cited as late only if they arrive more than 5 minutes past home room bell.
Cited late-> 5+
John arrived 17 minutes past the home room bell. Can we logically assume John was cited as late? No. John got a note from his mommy.
Students are cited as late if and only if they arrive more than 5 minutes past homeroom bell.
Cited as late <—> 5+
John arrived more than 17 minutes late. Can we logically assume John received a citation? YES Your Tort professor will not accept notes from your mommy, or doctor or the psychiatrist you visited after finishing this lesson.
What are some questions from previous tests that use biconditionals? Seeing this in LR-question context would be helpful for me to make sure I understand this concept.
Here, we tackle a special category of conditional relationships: those in which two conditions are both sufficient and necessary for each other. What are Bi-Conditional Claims: They are just the conjunction of a uni-conditional claim and its converse.
Bi-Conditional Claims:
Luke will become a Jedi if Yoda trains him and Luke will become a Jedi only if Yoda trains him
Yoda’s training is sufficient and necessary for Luke becoming a Jedi.
Translating into Lawgic: (yoda - t → luke- j) (luke-j → yoda - t) [&]
Bi-Conditional in Lawgic: (yoda-t) ← (luke-j) it then looks like this (yoda-t ←→ luke-j)
So what does the bi-conditional mean? It means that Yoda’s training is sufficient and necessary for Luke becoming a Jedi.
The contrapositive of this will look like this: (/yoda-t ← → /luke - j)
Indicators for Bi-Condirionals:
If and only if
If but only of
Then and only then
Or…but not both
If…then…but not otherwise
Examples for Bi-Conditionals:
Luke will become a Jedi if and only if Yoda trains him
Luke will become a Jedi if but only if Yoda trains him
Luke will become a Jedi if Yoda trains him but not otherwise.
[These are all sufficient and necessary conditionals]
RECAP:
Uni-conditionals express sufficiency (Yoda’s training is sufficient for Luke to become a Jedi) or necessity (Yoda’s training is necessary for Luke to become a Jedi).
A bi-conditional indicates that the two conditions are both sufficient and necessary for each other (Yoda’s training is both sufficient and necessary for Luke to become a Jedi). They are mutually dependent. One occurs if and only if the other occurs.
Bi-conditionals claims are represented in Lawgic with the bi-conditional arrow: ← →
It pouring is necessary and sufficient for it raining, it raining is necessary and sufficient for it pouring, they are mutually exclusive. If one happens then the other one happens, if one does not happen the other does not happen!
@jaydenca because it doesn't change the meaning. they are both necessary and sufficient for each other so it doesn't matter if we flip them or not, so, to simplify, we just don't flip (is what i would assume)
I really wish the time given in the study plan would at least correspond with the length of the video. The study plan claims this is a 2-minute section and the video is 6:49 long. Am I just supposed to ignore the video? This is happening frequently as I go through this study plan.
@thr107 Thanks for bringing this up -- we'll look into this. I think the plan is supposed to reflect the video time when there's a video, so if it's not, something's wonky.
I'm not sure if I remember it being discussed in 7sage material, but I know that this is true because of a Logic class I took.
Yoda is an animal but Luke is a person.
If you take this sentence and break down the clauses (Yoda is an animal) and (Luke is a person), there is no "relationship" per se between the two of them. Not a disjunction, not a conditional, not a biconditional, all that makes sense is a conjunction relationship. In Logic, the sentence can be translated as Yoda is an animal and Luke is a person.
To identify if two conditions are bi-conditional (both necessary and sufficient), look for language and logical cues that signal mutual dependence. Here’s a guide on how to identify a bi-conditional:
Language Cues: Certain phrases in English imply a bi-conditional relationship. These include:
"If and only if" (often abbreviated as "iff" in logic).
"If but only if."
"Then and only then."
"If... then... but not otherwise."
"Or... but not both."
When you see these phrases, they usually indicate that both conditions must be true together or false together.
Logical Testing of Both Directions: For a bi-conditional to be true, both of the following need to hold:
Sufficiency: Check if one condition guarantees the other.
If
A
A is sufficient for
B
B, then
A
→
B
A→B (if
A
A happens, then
B
B must happen).
Necessity: Check if the condition is also required.
If
B
B is necessary for
A
A, then
B
→
A
B→A (if
B
B does not happen, then
A
A cannot happen).
If both
A
→
B
A→B and
B
→
A
B→A hold, then you have a bi-conditional, written as
A
↔
B
A↔B.
Counterexamples: To confirm the conditions are truly mutually dependent, test for cases where one might happen without the other:
If you find that one condition can occur without the other, then they are not mutually dependent, meaning they are not bi-conditional.
Example Practice:
Uni-directional (Not Bi-conditional): "If it rains, the ground gets wet." This is only sufficient (raining is enough to make the ground wet), but it is not necessary (the ground can get wet by other means, like a sprinkler).
Bi-directional (Bi-conditional): "The light is on if and only if the switch is up." Here, the light being on and the switch being up are mutually dependent; they are true together or false together.
By using these strategies—checking language cues, testing for both directions of implication, and looking for counterexamples—you can determine if two conditions are bi-conditional.
#help why is "only if" (in the uni-conditional section) an operator that indicates Yoda training him is a necessary condition? Do the words following "only if" mean it's a necessary condition?
109 comments
man, is law school worth this? i feel like just when I begin to get it, i don't get it.
@zee.marie you make me feel seen
@zee.marie don't worry diva you are preaching to a choir
@zee.marie preach
my brain is fried, everything after the kick it up lesson is just mad confusing
so valid
@naomiy2k I feel the same way, but honestly, as you move forward I feel like the information starts to subconsciously make sense and you start to apply what you've learnt without necessarily digging deep into the trenches of you brain lol
@naomiy2k To my understanding the kick it up method is not something you need to use when evaluating a conditional claim, but is an option that makes it easier. At the moment I generally have not been thinking about it in drills but I think I eventually will when I train harder levels.
imma bout to crash out
dyinggg here
real
For those confused about uni-conditionals vs. bi-conditionals, consider these:
Uni-conditional example: "You will receive a medal if you finish the race in first-place."
We can logically create this diagram: finish race in first-place → receive a medal
Steve received a medal. Can we logically conclude that he therefore finished in first-place? No! The rule only tells us what happens if people finish first-place. Perhaps people who finished second and third also received a medal. Maybe every race participant received a medal! Who knows?
----------------------------------------------------------------
However, consider this bi-conditional example:
"You will receive a medal if and only if you finish the race in first-place."
The arrows now point both ways: finish in first place ↔ receive a medal
Christopher received a medal. Can we therefore logically conclude that he finished in first place? Yes!
(likewise, if we were just told that Christopher "finished in first-place," we could also logically conclude that he therefore received a medal).
This makes so much more sense - and a good way to think about it in this example is if is a sufficient indicator and only if is a necessary indicator thus its both necessary and sufficient
Good example, thanks!
Thank you for this
@dylancameron814 yesss u da besttt
Starting to feel a little excessive
Oh yeah, this is when the fun begins. Only thing you can do is to keep pressing forward. Sometimes you have to mess up applying these concepts in order for them to click. Don't get stuck here, keep going and keep failing: that's how you learn!! Don't give up :D
@RubemSantos Love this
@petvma Thanks. I hope you're fairing well with your studies.
Is it the case for anyone else that you understand how to work out these scenarios in English, but the Lawgic translation then makes it confusing to understand?
yes! i'm understanding it perfectly when it's in english but the second they bring out lawgic and conditionals and other nonsense, i get so confused. making me wonder if this is necesary for me to understand for the LSAT
@partenr Apparently you need this stuff for complex problems, right? Because I agree with you that it makes sense in English then mathy logic makes it confusing, seems like I am tripping myself up on purpose.
You commented months ago, what did you find out knowing what you know now?
I really wish I had watched Star Wars.
If you ever have the time, then you should start with the clone wars..... but not otherwise?
In my opinion the best way to explain/understand a bi-conditional claim is how it is taught in Math. It is taught as an 'iff' claim aka. an if and only if claim.
All an iff claim means is that each element implies the other:
Iff A then B, means: A --> B, and B --> A.
It is helpful to differentiate an iff claim from a regular conditional because of LSAT questions as so:
an animal is a zebra if and only if it has white and black stripes. (our biconditional claim in an argument on the LSAT)
Jerry is an animal that has black and white stripes. (an assertion made as part of the argument)
What inference can you make? (LR question on LSAT)
That Jerry is a zebra. (Answer derived by understanding that it is an iff claim, so both elements imply each other)
@sakinasohail01555IThanks for this
This is how I understand but not otherwise:
Basically stating not the sentence right before it.
For example
If Yoda trains him, Luke will become a Jedi
Otherwise
If Yoda does not train him, Luke will not become a Jedi
@dylancameron814 didn’t even look at the lesson and it clicked because of your comment.
Wish they would have used this example:
Student are cited as late only if they arrive more than 5 minutes past home room bell.
Cited late-> 5+
John arrived 17 minutes past the home room bell. Can we logically assume John was cited as late? No. John got a note from his mommy.
Students are cited as late if and only if they arrive more than 5 minutes past homeroom bell.
Cited as late <—> 5+
John arrived more than 17 minutes late. Can we logically assume John received a citation? YES Your Tort professor will not accept notes from your mommy, or doctor or the psychiatrist you visited after finishing this lesson.
I am overwhelmed.
same :((( I feel like there is so much to remember that im getting the stuff I already knew confused with this new info
I agree that its a lot to remember and gets overwhelming.
What are some questions from previous tests that use biconditionals? Seeing this in LR-question context would be helpful for me to make sure I understand this concept.
Okay, basically Yoda's training is necessary and guarantees that Luke will become a Jedi ?
clean version of my notes;
Here, we tackle a special category of conditional relationships: those in which two conditions are both sufficient and necessary for each other. What are Bi-Conditional Claims: They are just the conjunction of a uni-conditional claim and its converse.
Bi-Conditional Claims:
Luke will become a Jedi if Yoda trains him and Luke will become a Jedi only if Yoda trains him
Yoda’s training is sufficient and necessary for Luke becoming a Jedi.
Translating into Lawgic: (yoda - t → luke- j) (luke-j → yoda - t) [&]
Bi-Conditional in Lawgic: (yoda-t) ← (luke-j) it then looks like this (yoda-t ←→ luke-j)
So what does the bi-conditional mean? It means that Yoda’s training is sufficient and necessary for Luke becoming a Jedi.
The contrapositive of this will look like this: (/yoda-t ← → /luke - j)
Indicators for Bi-Condirionals:
If and only if
If but only of
Then and only then
Or…but not both
If…then…but not otherwise
Examples for Bi-Conditionals:
Luke will become a Jedi if and only if Yoda trains him
Luke will become a Jedi if but only if Yoda trains him
Luke will become a Jedi if Yoda trains him but not otherwise.
[These are all sufficient and necessary conditionals]
RECAP:
Uni-conditionals express sufficiency (Yoda’s training is sufficient for Luke to become a Jedi) or necessity (Yoda’s training is necessary for Luke to become a Jedi).
A bi-conditional indicates that the two conditions are both sufficient and necessary for each other (Yoda’s training is both sufficient and necessary for Luke to become a Jedi). They are mutually dependent. One occurs if and only if the other occurs.
Bi-conditionals claims are represented in Lawgic with the bi-conditional arrow: ← →
bi-conditionals are conditionals that drink matcha and listen to the cocteau twins
Example of a bi-conditional:
If it rains it pours
Rains->pours
It pours only if it rains
pours->rains
It pours if and only if it rains
Pours<->rains
It pouring is necessary and sufficient for it raining, it raining is necessary and sufficient for it pouring, they are mutually exclusive. If one happens then the other one happens, if one does not happen the other does not happen!
Just got back into studying for the LSAT after taking a 3-month break. Will be taking the test in November. Wish me luck!
@marikitten03 GOOD LUCK!
Why can't you just drop the sufficient part of the bi-conditional?
@BradyWade That's basically what's happening. Any sufficient clause becomes necessary, both clauses necessitate the other.
For the contrapositive version: Why, in uni-conditions, we flip and negate both, but in bi-conditions, we don't flip the claims?
@jaydenca because it doesn't change the meaning. they are both necessary and sufficient for each other so it doesn't matter if we flip them or not, so, to simplify, we just don't flip (is what i would assume)
I really wish the time given in the study plan would at least correspond with the length of the video. The study plan claims this is a 2-minute section and the video is 6:49 long. Am I just supposed to ignore the video? This is happening frequently as I go through this study plan.
@thr107 Thanks for bringing this up -- we'll look into this. I think the plan is supposed to reflect the video time when there's a video, so if it's not, something's wonky.
I don't quite understand why "or....but not both" would an indicator for bi-conditionals
Luke becomes a Jedi or Yoda does not train him but not both.
This is saying the same thing as: Luke becomes a Jedi if and only if Yoda trains him.
@mariafreese You are negating the one of the conditions here though.
A or B but not both is not the same as A or not B, but not both.
when was BUT described as a conjunction?
I'm not sure if I remember it being discussed in 7sage material, but I know that this is true because of a Logic class I took.
Yoda is an animal but Luke is a person.
If you take this sentence and break down the clauses (Yoda is an animal) and (Luke is a person), there is no "relationship" per se between the two of them. Not a disjunction, not a conditional, not a biconditional, all that makes sense is a conjunction relationship. In Logic, the sentence can be translated as Yoda is an animal and Luke is a person.
@rachelwallis1238 there was a lesson about it a little after the conjunction lesson.
To identify if two conditions are bi-conditional (both necessary and sufficient), look for language and logical cues that signal mutual dependence. Here’s a guide on how to identify a bi-conditional:
Language Cues: Certain phrases in English imply a bi-conditional relationship. These include:
"If and only if" (often abbreviated as "iff" in logic).
"If but only if."
"Then and only then."
"If... then... but not otherwise."
"Or... but not both."
When you see these phrases, they usually indicate that both conditions must be true together or false together.
Logical Testing of Both Directions: For a bi-conditional to be true, both of the following need to hold:
Sufficiency: Check if one condition guarantees the other.
If
A
A is sufficient for
B
B, then
A
→
B
A→B (if
A
A happens, then
B
B must happen).
Necessity: Check if the condition is also required.
If
B
B is necessary for
A
A, then
B
→
A
B→A (if
B
B does not happen, then
A
A cannot happen).
If both
A
→
B
A→B and
B
→
A
B→A hold, then you have a bi-conditional, written as
A
↔
B
A↔B.
Counterexamples: To confirm the conditions are truly mutually dependent, test for cases where one might happen without the other:
If you find that one condition can occur without the other, then they are not mutually dependent, meaning they are not bi-conditional.
Example Practice:
Uni-directional (Not Bi-conditional): "If it rains, the ground gets wet." This is only sufficient (raining is enough to make the ground wet), but it is not necessary (the ground can get wet by other means, like a sprinkler).
Bi-directional (Bi-conditional): "The light is on if and only if the switch is up." Here, the light being on and the switch being up are mutually dependent; they are true together or false together.
By using these strategies—checking language cues, testing for both directions of implication, and looking for counterexamples—you can determine if two conditions are bi-conditional.
Thank you for including the examples!
hey this was super helpful with the diagram you included. Thanks!
#help why is "only if" (in the uni-conditional section) an operator that indicates Yoda training him is a necessary condition? Do the words following "only if" mean it's a necessary condition?
"Only if" is a group two indicator, meaning you put what follows it as the necessary condition.
Yes, and more conceptually, "only if" is another way of saying "membership in subset X means membership in superset Y."
membership in becoming a jedi means membership in superset of being trained by Yoda.
Plain english...it's the only way!