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[Webinar] RC Mini Course in Three Sessions
Hey 7Sagers,
I'm teaching a live RC webinar mini course! Seriously, it's going to be me but live.
What is it?
We'll start with RC theory and fundamentals and then we'll apply it to select RC passages. Some materials in this webinar will overlap with what's in the Core Curriculum but most will be new. We're only using pre PT 36 materials. You don't need to have anything printed out, just follow along on screen or you can access the content via the Question Bank.
Who's it for?
I'll be picking a very very small group so everyone can interact. I will be asking lots of questions and will cold call just like in law school! Terrifyingly fun! Priority will be given to enrolled 7Sagers. You should have completed the Intro to Arguments, Grammar, and Main Point/Conclusion classes. No other background in RC necessary. If you're already advanced in RC, eh, this is probably not for you.
When?
Session 1: Monday, April 4
Session 2: Wednesday, April 6
Session 3: Friday, April 8
All sessions 8pm - 9:30pm (Eastern Time)
You have to commit to attending all three sessions. This is a long term relationship.
How do I sign up?
Step 1: Fill out this Google Survey before Sunday night 11:59pm.
Step 2: We'll do selections and email you next week.
Step 3: If selected, we'll ask you to place a small deposit to incentivize your attending all three sessions. If you do attend all three sessions in their entirety, we will refund you 100%. If you don't attend, you will not get your deposit back. Instead, we will donate your deposit to the political organization that you hate the most.
I'm teaching a live RC webinar mini course! Seriously, it's going to be me but live.
What is it?
We'll start with RC theory and fundamentals and then we'll apply it to select RC passages. Some materials in this webinar will overlap with what's in the Core Curriculum but most will be new. We're only using pre PT 36 materials. You don't need to have anything printed out, just follow along on screen or you can access the content via the Question Bank.
Who's it for?
I'll be picking a very very small group so everyone can interact. I will be asking lots of questions and will cold call just like in law school! Terrifyingly fun! Priority will be given to enrolled 7Sagers. You should have completed the Intro to Arguments, Grammar, and Main Point/Conclusion classes. No other background in RC necessary. If you're already advanced in RC, eh, this is probably not for you.
When?
Session 1: Monday, April 4
Session 2: Wednesday, April 6
Session 3: Friday, April 8
All sessions 8pm - 9:30pm (Eastern Time)
You have to commit to attending all three sessions. This is a long term relationship.
How do I sign up?
Step 1: Fill out this Google Survey before Sunday night 11:59pm.
Step 2: We'll do selections and email you next week.
Step 3: If selected, we'll ask you to place a small deposit to incentivize your attending all three sessions. If you do attend all three sessions in their entirety, we will refund you 100%. If you don't attend, you will not get your deposit back. Instead, we will donate your deposit to the political organization that you hate the most.
Comments
We're closing signups on Sunday night at 11:59pm.
We'll email everyone selection results by Tuesday morning.
I checked on Amazon just now and you can get excellent ones for $11. But probably should wait till we announce the selection unless you need one for something else.
Since I want this course to be interactive, I am only selecting four 7Sagers. This is an unfortunately small number. If you did not get an email from me, it means that you were not selected and I'm sorry about this. But, we will be making this webinar available online once it's done.
The 3rd one is wrong.
The argument tells us that some nocturnal predators are stealthy.
We cannot say for sure if some of those predators are spotted Chilean panthers.
It does not HAVE to be true. So, it fails the standard of MBT.
Anyone else want to weigh in?
No A are B
Some X are Y
Therefore: ?
Of course, it’s easy to see once it’s reduced to logic, but it’s such a grammatical mess it’s really difficult to translate; and that’s exactly what makes it so challenging.
CPHN --->/USS (If no spotted Chilean panthers that hunt at night use only their sense of smell)
NP <--s--> St (Some nocturnal predators are stealthy)
---------------------------------------
No non-trivial valid conclusion can be made
That was actually how I initially solved the problem, but I changed my mind (even though I had a feeling I was making a false overlap) and re-diagrammed it to
St <--s--> (NP) CPHN --->/USS
and chose (c) despite what (d) said: No "non-trivial" valid conclusion can be made.
Funny thing is I just remembered what he even meant by "non-trivial" inferences. Ha.. I seriously gotta read more attentively and review some materials. It was a really good question to learn my weakness.
CPHN -> /USS
Some NP are St
Based on the description of hunting at night, one can deduce that CPHN is a subset of NP. Equivocating the two would be incorrect, which is why some CPHN are St is inaccurate. However, we can still infer that some NP (CPHN) use more than their sense of smell (/USS).
Looking forward to the online post
The first proposition about the panthers is a negative existential claim, or, equivalently, a universal claim. Negative existentials/universals can be vacuously true if nothing satisfies the antecedent condition. So in this case, the first proposition is entirely consistent with there being no Chilean panthers at all in the world.
Imagine a world where the only nocturnal predators are house cats, and house cats only hunt with their sense of smell. Both propositions in the stimulus would be true, but (A) would be false.
(B) isn't correct because both propositions are true in a world where only house cats hunt nocturnally and where house cats use more than their sense of smell and where house cats are stealthy, and, lastly, where everything else in this world that uses only its sense of smell is not stealthy.
(C) isn't correct because both propositions are true in a world where no Chilean panthers exist.
Here’s my latest translation:
Spotted Chilean Panther that hunts at night -->
Use Only Sense of SmellNocturnal Predators -some--> Stealthy.
If we can say (and we have to really bend over backwards not to):
Spotted Chilean Panthers -some--> Nocturnal Predators
Then we can say:
Nocturnal Predators -some-->
Only Sense of SmellExistential fallacy aside, that’s a valid argument structure.
Here is the abridged first-order logic translation of the first proposition:
¬∃x(SpottedChileanPantherThatHuntsAtNight(x) ∧ UsesOnlySenseOfSmell(x))
This is equivalent to
∀x(SpottedChileanPantherThatHuntsAtNight(x) → ¬UsesOnlySenseOfSmell(x))
Inferring from this the following sentence:
∃x(SpottedChileanPantherThatHuntsAtNight(x) ∧ ¬UsesOnlySenseOfSmell(x))
is a textbook fallacy covered in every first-order logic course. From a universal, we simply can't infer an existential. From "no spotted Chilean panthers blah blah blah", we simply cannot validly infer that there are any spotted Chilean panthers at all. And there are some very good reasons why we can't make this inference.
I just got into a lot of trouble before 7Sage by not shifting my thinking from formal logic to LSAT logic. So in my earlier prep, I would use the horseshoe to indicate a conditional statement and all the “there exists an x such that,” proper logical language, that kind of thing. When I started 7Sage I told myself I was going to abandon all that and exclusively use the methods and notations of 7Sage, and for the purposes of the LSAT it’s been a lot more effective.
So I guess my interest in this is that I can’t recall an existential fallacy lesson. “No” is simply a group 4 indicator- negate necessary and done, no existential strings attached. I think at some point JY says something about a unicorn, the classic example of this existential fallacy, so I’m wondering if maybe we do get this somewhere, but I just can’t find the lesson.
So it’s like I’m experiencing some kind of self aware cognitive dissonance or something. Hard, formal Aristotelian/Boolean logic seems to be crashing into LSAT logic and I just don’t know what to do with that. Right now, I only care about LSAT logic, so I just want to make sure that’s the understanding I’m arriving at.
@jessicalj LSAT logic operates from classical assumptions (non-contradiction, excluded middle, double negation elimination, etc.), so my comments are entirely consistent with LSAT logic. I would just be very, very surprised if something like this showed up on the LSAT because I've never seen a test question abuse vacuous truths.