PT 64 S1 Q23 Forum

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Walrus

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PT 64 S1 Q23

Post by Walrus » Sat Dec 28, 2013 12:47 am

Can't understand why D is better than B :( .

Stimulus

P1: F-->~C (Feelings are not within one's control)
P2: P and ~C-->~S (Promise do to something not within one's control makes no sense)
IC: P and L and F-->~S (If "love" refers to a feeling, then this promise makes no sense)
FC: ~(P and L and F) ( Love should not be referred to feelings in promises)

Q type: Sufficient assumption

D) SA: P-->S
If we assume that
P-->S is true
then
(IC) P and L and F-->~S
is in contradiction with P-->S
Therefore
P and L and F cannot exist together or ~(P and L and F)
Possibilities:
PL;PF;LF;L;P;F

B) SA: P-->C
If we assume that
P-->C is true
then
(P1) F-->~C and (SA)P-->C
will give us
P-->C-->~F
Therefore
P and L and F cannot exist together or ~(P and L and F)
Possibilities
PL;P;L;F;LF

Help me to find out where I did a mistake please.

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Silvermanlsat

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Re: PT 64 S1 Q23

Post by Silvermanlsat » Sat Dec 28, 2013 3:54 am

Note the following lines: If love refers to a feeling, then the promise to love until death do us part makes no sense because feelings are not within one's control, and a promise to do something not within one's control makes no sense.

The above lines are entirely logical. In other words, the conclusion that the promise to love until death do us part makes no sense follows logically from the premises that no promise not within one's control makes sense, and the promise to love is a promise not within one's control. So, we have concluded that point; namely, that to love until death do us part makes no sense.

We are then told that therefore that no one should take love in this context to refer to feelings. But that would only be true if it were also true that promises should never be interpreted in such a way that they make no sense. Imagine the opposite were true. Imagine it were true that promises should sometimes (or always) be interpreted in a way that they make no sense. If that were true, then we would not be prevented from taking love in this context to refer to feelings, even though doing so makes no sense.

So, for the conclusion (that we should never take the promise of love to refer to feelings) to follow logically, it must be assumed that promises should not be interpreted in such a way that they make no sense (choice D).

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Christine (MLSAT)

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Re: PT 64 S1 Q23

Post by Christine (MLSAT) » Sat Dec 28, 2013 1:26 pm

The main problem that you are having is that you are trying to force everything into conditional logic notation, even when it probably shouldn't be. In doing this, you are losing crucial bits of information.

For intance, when you force answer choice (B) into "P-->C" and (D) into "P-->S", this looks like "all promises are controllable" and "all promises make sense". But (B) didn't say "all promises are controlled or controllable" - it said that people should not make promises that aren't within their control. That part is important, and your shorthand erases it.

Similarly, (D) does not say "All promises make sense", but rather that people should not interpret promises to mean things that don't make sense.

(B) and (D) are both recommendations for behavior rather than strict conditionals, the the behavior they recommend (i.e., the VERB), is important.

Now that you're looking at the verbs, notice that (B)'s recommendation only applies to people actually making promises. Our conclusion got all the way to 'no one in universe should interpret blah blah blah'. (D)'s recommendation applies to all people doing any interpreting, so that moves us toward the conclusion.

I recognize the allure of 'mathizing' all stimuli, and when formal logic is truly at play, it's super useful. But forcing statements that don't lend themselves well to this type of shorthand will usually result in substantial information loss in translation. That's exactly what you experienced here.

Walrus

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Re: PT 64 S1 Q23

Post by Walrus » Sat Dec 28, 2013 4:25 pm

Thank you for responses!
You are right Christine, It seems that there is no clear way to combine prescriptive language and conditional logic in this argument.

But even without diagramming I can't see why "D" is better than "B"
(B)'s recommendation only applies to people actually making promises. Our conclusion got all the way to 'no one in universe should interpret blah blah blah'. (D)'s recommendation applies to all people doing any interpreting, so that moves us toward the conclusion.
Do you agree that conclusion is recommendation to avoid using (Promise and Love Referring to feelings) together at the same time?

It seems to me that conclusion isn't talking about all possible worlds in universe when it says that love shouldn't be referred to feelings. It says love shouldn't be referred to feelings "In this context". What context? As I understand the context of promises.

"B" says - People should not make promises to do something that is not within their control. Positive form of "B" is People should make promises to do only those things that are within their control.

But if love refers to feelings it is not under one's control. Therefore love shouldn't be referred to feeling in the context of promise.

"B" looks like SA to me.
What do you think?

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Christine (MLSAT)

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Re: PT 64 S1 Q23

Post by Christine (MLSAT) » Sat Dec 28, 2013 5:01 pm

You're still overshorthanding and losing information. The conclusion is that no one should interpret love to mean feelings (in the context of promises). That includes the people making the promises, but it also includes people who are NOT making the promises. It includes everyone!

(B) is only a recommendation about the kind of promises people should make. If (B) were true, everyone might still interpret love to mean feelings in promises! The result of those combined would be that no one should ever make a promise to love, but that's ok - there's nothing that guarantees the conclusion about everyone's interpretation.

(D) does the job by saying that no one (whether they are making promises or not!) should interpret things in a way that's senseless. Interpreting love to mean feelings (in the context of promises) would make those promises not make sense. So (D) says we can't do that! That would mean then that no one can interpret a love to mean feelings (in the context of promises) - and that's what the conclusion says! Conclusion guaranteed!

You're just focusing on a sort of abstract idea of whether love=feelings=control. But the real distinction here is whether those leaps are made in the making of promises or the interpreting of promises. Those are completely different areas, and the conclusion is about interpretation.

Does that help?

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Walrus

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Re: PT 64 S1 Q23

Post by Walrus » Sat Dec 28, 2013 7:03 pm

My head is ready to explode.
:idea:

So "B" is talking only about people who MAKE promises. And if they are prescribed to make promises only about things that are under their control, they should not interpret love in referring to feelings in their promises.

But conclusion is talking about
- Promise giver
- Promise taker
- All other people who are aware about promise

"B" only bridges the gap for promise giver.

And "D" bridges the gap for everyone

Thank you Christine!

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Christine (MLSAT)

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Re: PT 64 S1 Q23

Post by Christine (MLSAT) » Sat Jan 04, 2014 11:18 am

Walrus wrote:My head is ready to explode.
:idea:

So "B" is talking only about people who MAKE promises. And if they are prescribed to make promises only about things that are under their control, they should not interpret love in referring to feelings in their promises.

But conclusion is talking about
- Promise giver
- Promise taker
- All other people who are aware about promise

"B" only bridges the gap for promise giver.

And "D" bridges the gap for everyone

Thank you Christine!
You're so close to fully getting this one!

Okay, what you're completely correct about here is that the conclusion is talking about promise givers, takers, and anyone else. And (B) only talks about people who make promises. That alone is enough tell us that it is wrong!

But I want you to dig a little deeper. The bolded above is not actually what (B) means.

All (B) has told us is that people shouldn't make promises about things outside their control. And we know from the premises that feelings are outside our control. So from those two pieces, we can validly conclude that people shouldn't make promises about feelings.

So what about love? Well, we don't know from all this whether it is a feeling or not. If it *is* a feeling, then the above would mean that people shouldn't make promises about love. If it is *not* a feeling then maybe people can. But we aren't given any information in (B) about whether love is a feeling or not, nor whether people (makers of promises or otherwise) should interpret love as a feeling.

Do you see? (B) only gives us information about the types of promises one ought to make. It never says anything about how those makers should interpret "love".

There are *two* major problems with (B) here:
1) as you already saw, it is only about the makers of promises, while the conclusion is about everyone
2) it is only about what promises should be made, while the conclusion is about how love should be interpretted

I hope this helps!

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