I don't understand the last paragraph "The only problem is that you made up your own premise B -> A. The actual premise is A -> B. You confused sufficiency for necessity."
The rest of the lesson makes sense, but I'm totally lost when I read that. Maybe make a video or remove/clarify that paragraph? I don't see what that really adds here.
Valid conclusion: Only dogs play outside. Blanche plays outside. Therefore, Blanche is a dog.
Invalid conclusion: All dogs play outside. Blanche plays outside. Therefore, Blanche is a dog.
In the invalid conclusion, Blanche could be a part of another group since it does not explicitly state that you have to be a dog to play outside. She could be human, a cat, etc.
Ok so I also found this lesson confusing. What I think the key take away here is that just because the necessary condition is true tells us nothing about the sufficient condition. That's it.
My example:
All moms use the kitchen. I use the kitchen. Therefore, I am a mom
Lawgic:
Moms -> use kitchen
I KITCHEN
--
I MOM
This is Invalid. WHY? Because I'M NOT A MOM. I AM A SINGLE DUDE. Just because I am using the kitchen does that mean I am a mom? NO!
If you thought me using the kitchen meant I'm a mom you are confusing sufficiency for necessity. You are saying that using the kitchen is SUFFICENT for being a mom. you are saying "All those who use the kitchen are mom".
AFFIRMING THE NECESSARY CONDITION TELLS YOU NOTHING ABOUT THE SUFFICIENT CONDITION
All we know from the stimulus is that All moms use the kitchen.
Mom = Sufficient
Using kitchen = Necessary
If I affirm the necessary condition by saying "I use the kitchen" does that tell you anything about if I am a mom or not?
If the necessary condition is satisfied, it yields no information about the sufficient condition. The sufficient condition could be true or could be false.
"All" is from group 1-necessity conditional indicators, where what follows immediately after the indicator, in this case "all", is the necessary condition. So, lawgic would be:
All Jedi use the Force.
J -> F
Dooku use force:
D -> F
Dooku is Jedi:
D -> J. This conclusion is not valid from the given premise.
In case of "only", its from group 2-sufficiency conditional indicators. What follows immediately after the indicator, "only", is the sufficient condition. So, lawgic would be:
Only Jedi use the Force.
F -> J
Dooku uses the Force.
D -> F
Chaining conditionals:
D -> F -> J
D -> J
We can infer from the above that Dooku is Jedi, which is the conclusion in the argument.
What has made this easier for me is realizing that all is not the same as only. All refers to everything of a certain group. Only is more strict about the rules.
All dogs drink water. Other animals can drink water too.
ONLY dogs drink water. No other animals drink water.
I am also confused by this but I am a little new to studying for this oldest trick in the book that keeps kicking my butt.
All Jedi… Is that not a sufficient condition because they used “all”? All Jedi us the force so using the force is a sufficient condition of being a Jedi?
Only Jedi…is that not a necessary condition because they used “only”? While using the force is a necessary condition of being a Jedi it is not sufficient to guarantee membership in the Jedi order simply because one uses the force?
Only Arabic-speakers get PhDs. Chris is an Arabic speaker. Therefore Chris gets a PhD.
If gets a PhD, then an Arabic Speaker, written
PhD->Arabic-speaker
Now here's where you don't want to mess up. It says Chris is in that "Arabic-Speaker" portion, or in other words, he's someone in the necessary condition position. But we can't work backwards. We can't say if Chris (the necessary) speaks Arabic then he gets a PhD.
It's easier to see if we use three topics, as it builds on earlier lessons:
Would you say this can be simplified to: "If the sufficient condition is false, the necessary condition can be true or false", and "if the necessary condition is true, the sufficient condition can be true or false"?
I do not understand the second example. If the conditional indicator is Only, that translates to logic Uses Force --> Jedi. Since Dooku uses the force, he triggered the sufficient and is a Jedi. This is a valid logic. But why did the text say I made up my own premise? If the conditional indicator is only, I did not make anything up did I? it's very confusing.
If it says all jedi use the force, and count doku uses the force. Its reasonable to assume that hes a jedi based on the premises. Dont understand why thats not valid
#feedback Echoing what has been said, but videos would be really helpful. I don't understand what premise is being made up in the second half of these lessons.
Is it just me or does the x before A and B confuse anyone into thinking it's a negation.??... I know that negation is /A but x intuitively represents 'not' in my head agh!
I really don't like the examples used in 7Sage. Why do you always stick to the Jedi/force/Yoda whatever thing? For people who never watch the show or have absolutely zero interest in it, it's not helpful for studying at all
Why is the Lawgic shorthand for Jedi and Force all of the sudden A and B instead of J and F in these examples? It makes it impossible to match english to the Lawgic shorthand in order to follow along. What are we doing here? #feedback
hello, i am a little confused bc in the conditional reasoning sets and supersets
it said all mammals are cats. Garfield is a cat. therefore Garfield is a mammal. how is that a valid argument but not this. bc i thought the point of subset and superset. is the second premise proving that variable x (garfield) is a category of B, so we can conclude x is also a
For anyone who is having a hard time grasping this: Just because something is B, doesn’t meant mean it’s A. In other words: Meeting the necessary condition doesn’t tell us whether something also = sufficient condition
I think I see how negation is key here (someone correct me if I’m wrong).
For example, if we take the statement…
"All Jedi use the Force" and negate it, we get "Some Jedi don't use the Force.”
Original: J → F
Negated: J ←s→ /F
This shows that it's possible for someone to be a Jedi without using the Force. So, going back to the original argument:
"All Jedi use the Force. Count Dooku uses the Force. Therefore, Count Dooku is a Jedi."
It is invalid because it’s possible that some Jedi don't use the Force. It is not enough evidence to say Count Dooku is a Jedi just because he uses the Force.
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118 comments
I got home from reviewing demands and medical records to come and read! ughhh where are the videos!!
Failing a sufficient condition doesn't mean they cannot meet the necessary condition
Failing a necessary condition does mean that they cannot meet the sufficient condition
Meeting a sufficient condition does mean that they meet the necessary condition
Meeting a necessary condition does not mean that they meet the sufficient condition
I don't understand the last paragraph "The only problem is that you made up your own premise B -> A. The actual premise is A -> B. You confused sufficiency for necessity."
The rest of the lesson makes sense, but I'm totally lost when I read that. Maybe make a video or remove/clarify that paragraph? I don't see what that really adds here.
Valid conclusion: Only dogs play outside. Blanche plays outside. Therefore, Blanche is a dog.
Invalid conclusion: All dogs play outside. Blanche plays outside. Therefore, Blanche is a dog.
In the invalid conclusion, Blanche could be a part of another group since it does not explicitly state that you have to be a dog to play outside. She could be human, a cat, etc.
Ok so I also found this lesson confusing. What I think the key take away here is that just because the necessary condition is true tells us nothing about the sufficient condition. That's it.
My example:
All moms use the kitchen. I use the kitchen. Therefore, I am a mom
Lawgic:
Moms -> use kitchen
I KITCHEN
--
I MOM
This is Invalid. WHY? Because I'M NOT A MOM. I AM A SINGLE DUDE. Just because I am using the kitchen does that mean I am a mom? NO!
If you thought me using the kitchen meant I'm a mom you are confusing sufficiency for necessity. You are saying that using the kitchen is SUFFICENT for being a mom. you are saying "All those who use the kitchen are mom".
AFFIRMING THE NECESSARY CONDITION TELLS YOU NOTHING ABOUT THE SUFFICIENT CONDITION
All we know from the stimulus is that All moms use the kitchen.
Mom = Sufficient
Using kitchen = Necessary
If I affirm the necessary condition by saying "I use the kitchen" does that tell you anything about if I am a mom or not?
If the necessary condition is satisfied, it yields no information about the sufficient condition. The sufficient condition could be true or could be false.
Did I get it wrong?
"All" is from group 1-necessity conditional indicators, where what follows immediately after the indicator, in this case "all", is the necessary condition. So, lawgic would be:
All Jedi use the Force.
J -> F
Dooku use force:
D -> F
Dooku is Jedi:
D -> J. This conclusion is not valid from the given premise.
In case of "only", its from group 2-sufficiency conditional indicators. What follows immediately after the indicator, "only", is the sufficient condition. So, lawgic would be:
Only Jedi use the Force.
F -> J
Dooku uses the Force.
D -> F
Chaining conditionals:
D -> F -> J
D -> J
We can infer from the above that Dooku is Jedi, which is the conclusion in the argument.
What has made this easier for me is realizing that all is not the same as only. All refers to everything of a certain group. Only is more strict about the rules.
All dogs drink water. Other animals can drink water too.
ONLY dogs drink water. No other animals drink water.
I am also confused by this but I am a little new to studying for this oldest trick in the book that keeps kicking my butt.
All Jedi… Is that not a sufficient condition because they used “all”? All Jedi us the force so using the force is a sufficient condition of being a Jedi?
Only Jedi…is that not a necessary condition because they used “only”? While using the force is a necessary condition of being a Jedi it is not sufficient to guarantee membership in the Jedi order simply because one uses the force?
how is this any different than confusing sufficiency for necessity? I guess I don't understand why this is separate
#feedback
That last paragraph keeps tripping me up. A video would prob explain this better to avoid confusion.
SO in form it would be
A-->B
B
-------
nothing - we cannot conclude anything about A
I know this is simple but I want to make sure I am not missing it.
... did you ever hear the tragedy of Darth Plagueis the Wise?
Keep it simple: Think about this:
Only Arabic-speakers get PhDs. Chris is an Arabic speaker. Therefore Chris gets a PhD.
If gets a PhD, then an Arabic Speaker, written
PhD->Arabic-speaker
Now here's where you don't want to mess up. It says Chris is in that "Arabic-Speaker" portion, or in other words, he's someone in the necessary condition position. But we can't work backwards. We can't say if Chris (the necessary) speaks Arabic then he gets a PhD.
It's easier to see if we use three topics, as it builds on earlier lessons:
A->B->C
We can't say "if C, then B"
Would you say this can be simplified to: "If the sufficient condition is false, the necessary condition can be true or false", and "if the necessary condition is true, the sufficient condition can be true or false"?
I do not understand the second example. If the conditional indicator is Only, that translates to logic Uses Force --> Jedi. Since Dooku uses the force, he triggered the sufficient and is a Jedi. This is a valid logic. But why did the text say I made up my own premise? If the conditional indicator is only, I did not make anything up did I? it's very confusing.
If it says all jedi use the force, and count doku uses the force. Its reasonable to assume that hes a jedi based on the premises. Dont understand why thats not valid
#feedback Echoing what has been said, but videos would be really helpful. I don't understand what premise is being made up in the second half of these lessons.
Is it just me or does the x before A and B confuse anyone into thinking it's a negation.??... I know that negation is /A but x intuitively represents 'not' in my head agh!
Pretty please bring back videos.... #Feedback
I really don't like the examples used in 7Sage. Why do you always stick to the Jedi/force/Yoda whatever thing? For people who never watch the show or have absolutely zero interest in it, it's not helpful for studying at all
Why is the Lawgic shorthand for Jedi and Force all of the sudden A and B instead of J and F in these examples? It makes it impossible to match english to the Lawgic shorthand in order to follow along. What are we doing here? #feedback
hello, i am a little confused bc in the conditional reasoning sets and supersets
it said all mammals are cats. Garfield is a cat. therefore Garfield is a mammal. how is that a valid argument but not this. bc i thought the point of subset and superset. is the second premise proving that variable x (garfield) is a category of B, so we can conclude x is also a
Okay so this would be like saying:
Every Californian lives on Main Street. Sarah lives on Main Street. Therefore Sarah lives in California.
For anyone who is having a hard time grasping this: Just because something is B, doesn’t meant mean it’s A. In other words: Meeting the necessary condition doesn’t tell us whether something also = sufficient condition
I think I see how negation is key here (someone correct me if I’m wrong).
For example, if we take the statement…
"All Jedi use the Force" and negate it, we get "Some Jedi don't use the Force.”
Original: J → F
Negated: J ←s→ /F
This shows that it's possible for someone to be a Jedi without using the Force. So, going back to the original argument:
"All Jedi use the Force. Count Dooku uses the Force. Therefore, Count Dooku is a Jedi."
It is invalid because it’s possible that some Jedi don't use the Force. It is not enough evidence to say Count Dooku is a Jedi just because he uses the Force.