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General questions relating to LSAT Logical Reasoning.
 kwcflynn
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#65665
Hi!

I recently purchased the flashcards, and so far they are handy! However, I have questions about some answers to the flashcards:

Q - Identify the Premise(s): Margaret only goes to the movies on rainy days, and today is a very rainy day. Thus we can conclude that Margaret is going to a movie today.
I understand that "Margaret only goes to the movies on rainy days" and "Today is a very rainy day" are the premises, but the explanation claims that the author draws an invalid conclusion that Margaret is going to a movie today and further asserts the argument would be valid if it said "Margaret always goes to movies on rainy days." Why is that the case? Is always a sufficient condition indicator? Perhaps I do not know how to diagram the conditional reasoning found in the premise.

Thank you,

Kevin
 Brook Miscoski
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#65720
kwcflynn,

Yes, "always" is a sufficiency indicator, while "only" is a necessity indicator.

"Only goes to movies when it rains" means Movie :arrow: Rain.

"Always goes to movies when it rains" or "Goes to movies when it rains" ("when" is also a sufficiency indicator) means Rains :arrow: Movie
 kwcflynn
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#65734
In "Only goes to movies when it rains," how can you determine what the sufficient and necessary are? I would think that 'when' modifies Rain (making it the sufficient) and 'only' modifies Movies (making it the necessary). Because doesn't it say, "When it rains, Margaret only goes to the movies."

Thank you, Brook!

Kevin
 kwcflynn
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#65758
Hi!

I was hoping if I could a response from anyone regarding my question. I am a little stuck and would greatly appreciate it.

Thank you very much!

Kevin
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 Dave Killoran
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#65761
Hi Kevin,

Let me try to help here!

First, the English language is so flexible that it allows for many different configurations, which is where a lot of confusion with these types of statements arises. In Brook's example, technically what's happened is that the necessary indicator phrase "only when" has been split up into separate parts, leading to your confusion. The sentence would be easier to understand as:

  • "Jimmy goes to movies only when it rains"
"Only when" is necessary condition indicator, meaning the diagram is MovieJimmy :arrow: Rain.


Second, in the original argument from the card, we have the following structure:

  • Premise: Margaret only goes to the movies on rainy days = MovieMargaret :arrow: Rainy Day
    Premise: today is a very rainy day = Rainy Day

    Conclusion: Thus we can conclude that Margaret is going to a movie today = MovieMargaret

    That's a Mistaken Reversal, hence the error.

Last, in the proposed revision of the first premise, the substitution would change the meaning so that if rain is occurring, then she goes to the movies (Rainy Day :arrow: MovieMargaret), turning the argument into a straightforward restatement form.


If you get a chance, search through my many posts here and look for conditional discussions—I talk about this kind of stuff a lot :-D

Thanks!
 kwcflynn
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#65769
Thank you, Dave! I understand that now.

One more question - are condition indicators that are split, just as "only when" above, common? I don't remember seeing a lot of them in questions.

Thanks again!

Kevin
 kwcflynn
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#65880
Thanks so much, Dave!
 kwcflynn
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#66882
Hi,

I encountered three additional questions from the flashcards that had very surprising answers (to me):

1. What reasoning element is typically introduced by "Responsible for"?
2. What reasoning element is generally introduced by "Because of"?
3. What reasoning element is generally introduced by "Determined by"?

1. Cause - I would think the answer would be Effect. Take a look at this example, "Excessive hunting and poaching in the rainforest is responsible for the drastic population decline of jaguars." In this case, the hunting and poaching cause the decrease in jaguar population.

2. Effect - I had thought "Because of" indicated Cause. For example, "Because of the hot weather, Somerville residents avoided leaving their air-conditioned homes." The hot weather, introduced by "Because of," led to people staying indoors. Also, I view "Because of" synonymous with "due to" - another causal indicator that introduces the cause element.

3. Effect - I simply do not understand how "Determined by" typically introduces the effect in a causal relationship. "Promoted by" and "induced by" are both introduce the cause, and they both have nearly identical meaning to "Determined by."

I am very aware that each of these questions include typically or generally, which makes these answers not definite. However, I hope to learn general rules of thumb as I review these questions from the flashcards. If anyone is available to help, I would sincerely appreciate it!

THANK YOU

Kevin
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 KelseyWoods
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#66889
Hi Kevin!

Can you let us know the numbers of the flashcards you are referring to? It will help us make sure we're answering your question as thoroughly as possible. Thank you!

Best,
Kelsey

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