Formal Logic Questions (to which I'd appreciate answers)

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jpSartre
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Formal Logic Questions (to which I'd appreciate answers)

Postby jpSartre » Fri Apr 09, 2010 1:03 pm

I've been struggling to understand these fully. Could someone explain them?

1. All students that walk to school go home for lunch. Therefore, some students with part time jobs do not walk to school.

This follows if what assumption is made?

Set-up:

W -> L

___________________
P --s-> -W

Answer: -B --s-> P (some students who don't go to lunch have a part time job

How??




2.

Human beings exhibit goal-oriented behavior without conscious awareness. Thus, establishing that a non-human animal is intelligent will not establish that they have consciousness.

What is assumed?


Set-up:

G without C
I does not entail C

Answer: goal oriented behavior requires intelligence (G -> I)

How do you diagram "without" or something like "does not entail?" and it seems that the answer should be (I -> G)...

Thanks in advance people

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Sentry
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby Sentry » Fri Apr 09, 2010 2:06 pm

.
Last edited by Sentry on Wed Sep 21, 2011 9:51 pm, edited 1 time in total.

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KibblesAndVick
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby KibblesAndVick » Fri Apr 09, 2010 2:25 pm

For Question 1, you need to take the contra-positive of the first statement. If you Walk To School (W2S) ----> you go home for lunch (H4L). Therefore, [strike]H4l[/strike] ------> [strike]W2S[/strike].

In the 2nd statement, the connection you're trying to make is from some students with part time jobs ------> to don't walk to school([strike]W2S[/strike]). From the contra-positive above this follows logically if we assume that some students with part times jobs don't go home for lunch (because if they don't go home for lunch, they don't walk to school).

I don't see the logic of question 2, what PT is it from?

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jpSartre
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby jpSartre » Fri Apr 09, 2010 2:32 pm

1. I guess I was getting hung up on the wording, because the wording in the answer goes: "some who don't go home for lunch have part time jobs", where the common sense way (for me) to say it is "some with part time jobs don't go home for lunch"

2. is from PT 40, section 2 #17

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KibblesAndVick
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby KibblesAndVick » Fri Apr 09, 2010 2:43 pm

jpSartre wrote:1. I guess I was getting hung up on the wording, because the wording goes: "some who don't go home for lunch have part time jobs", where the common sense way (for me) to say it is "some with part time jobs don't go home for lunch"

2. if from PT 40, section 2 #17


On LR questions that involved "air tight" formal logic I always found it easiest to just diagram the sentences using abbreviations. If I tried to do the logic "in plain English" I would get too hung up on actually thinking about what the question is saying :P. This is silly, but sometimes the easiest way to solve formal logic questions is to just treat it like a math problem (If X then Y, If [strike]X[/strike] then Z etc.)

I think LSAC should get away from intense formal logic in LR and keep it in the LG sections. But, your purpose is obviously to answer every question they throw at you correctly. Criticizing their methods won't improve your score :D.

Are you sure it's PT 40, section 2? PT 40 by my records is June 2003. Section 2 is logic games. This could be an organizational fail on my part. What is the date of the test?

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jpSartre
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby jpSartre » Fri Apr 09, 2010 2:45 pm

Ah yeah, sorry I should have typed 49. More like a +/-3cm keyboard precision fail on my part

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KibblesAndVick
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby KibblesAndVick » Fri Apr 09, 2010 2:58 pm

It seems I can't find my copy of 49..... now it is an organizational fail on my part :D
hmmm I know I have that sucker someplace

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jpSartre
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby jpSartre » Fri Apr 09, 2010 3:35 pm

Here's it in full:

Human beings can exhibit complex, goal-oriented behavior without conscious awareness of what they are going. Thus, merely establishing that nonhuman animals are intelligent will not establish that they have consciousness.

Which is an assumption on which the arguement depends?

a) Complex, goal-oriented behavior requires intelligence

b) links consciousness an intelligence so is ruled out

c) links consciousness an intelligence so is ruled out

d) links consciousness an intelligence so is ruled out

e) links complexity and goal-oriented behavior so is ruled out.

a has to be true, and it is, but I can't figure out the formal mechanics behind the stimulus. The first statement seems to defy conventional notation

If I'm following conditional notation rules correctly, it would be:

if not capable of goal oriented behavior, then conscious. But that's not true.

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KibblesAndVick
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby KibblesAndVick » Fri Apr 09, 2010 3:41 pm

I'm stumped... I also can't finish my homework because this is haunting my brain haha

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TheIdiot
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Re: Formal Logic Questions (to which I'd appreciate answers)

Postby TheIdiot » Fri Apr 09, 2010 4:24 pm

Way rusty with this stuff, so take it for what it's worth:

Premise: complex-goal oriented behavior does not require consciousness
Conclusion: intelligence does not require consciousness

Question: If CGB does not require C, then how do we know that I does not require C.

Solution: Complex-goal oriented behavior requires intelligence.

In other words, if you can have goal-oriented behavior without consciousness, and all goal-oriented behavior implies intelligence, then you can have intelligence without consciousness.

More formally:
A does not require B [A without B]
A does require C [All A's are C's]

If this is true, then those C’s that are also A’s, are also not necessarily B's. Thus, we can have C without B.

So, relative to how you put it:
Premise: A without B
Conclusion: C without B

Assumption: A implies C




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