"As long as" - Formal Logic? Forum

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MissLucky

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"As long as" - Formal Logic?

Post by MissLucky » Fri Oct 01, 2010 4:18 pm

for example, the first line of Q23 in PT53 (section 3) states:

"A species can survive a change in environment, as long as the change is not too rapid."

translating this statement into some kind of Formal Logic was by no means necessary to this question (and i'm not even sure if it's possible), but I am curious as to what "as long as" signifies.

Would this sentence be properly represented as such:
If species survive a change in environment --> the change is not too rapid
OR
If the change is not too rapid --> species survive a change in environment

??

Thank you!

dakatz

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Re: "As long as" - Formal Logic?

Post by dakatz » Fri Oct 01, 2010 4:20 pm

MissLucky wrote:for example, the first line of Q23 in PT53 (section 3) states:

"A species can survive a change in environment, as long as the change is not too rapid."

translating this statement into some kind of Formal Logic was by no means necessary to this question (and i'm not even sure if it's possible), but I am curious as to what "as long as" signifies.

Would this sentence be properly represented as such:
If species survive a change in environment --> the change is not too rapid
OR
If the change is not too rapid --> species survive a change in environment

??

Thank you!
The former of the 2. If a species survives a change in environment ---> the change is not too rapid

MissLucky

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Re: "As long as" - Formal Logic?

Post by MissLucky » Fri Oct 01, 2010 4:25 pm

nice - thanks!

cubswin

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Re: "As long as" - Formal Logic?

Post by cubswin » Fri Oct 01, 2010 4:37 pm

You've already been told the correct answer, but to explain it a little more, "as long as" should sound like a requirement or a necessary condition. Requirements always go on the right side of the arrow. Consider a simpler example:

"Jimmy can watch TV after dinner as long as he eats his vegetables."

Jimmy can watch TV after dinner ---> Jimmy ate his vegetables.

MissLucky

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Re: "As long as" - Formal Logic?

Post by MissLucky » Fri Oct 01, 2010 4:50 pm

okay, knowing what "as long as" indicates is actually making it more difficult to see (D) as fully parallel in Question 23 (obviously considering all the other answer choices it easily takes the cake, but this is for the sake of analysis).

The stimulus evidence says:
If a species can survive a change in environment --> the change is not too rapid
...and given this, it conclusion goes on to explain where the threat to survival comes from (i.e. goes on to explain the opposite of the SUFFICIENT clause)


And the correct parallel response was (D) where the evidence states:

If people know what change will bring --> people do not fear change
...and given this, its conclusion goes on to explain where the employees fear comes from (i.e. goes on to explain the opposite of the RESULT clause)

This evidence doesn't exactly seem parallel to me - thoughts? what am I missing?

thnx!

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CodingIsLove

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Re: "As long as" - Formal Logic?

Post by CodingIsLove » Fri Jun 05, 2020 1:05 pm

dakatz wrote:
Fri Oct 01, 2010 4:20 pm
MissLucky wrote:for example, the first line of Q23 in PT53 (section 3) states:

"A species can survive a change in environment, as long as the change is not too rapid."

translating this statement into some kind of Formal Logic was by no means necessary to this question (and i'm not even sure if it's possible), but I am curious as to what "as long as" signifies.

Would this sentence be properly represented as such:
If species survive a change in environment --> the change is not too rapid
OR
If the change is not too rapid --> species survive a change in environment

??

Thank you!
The former of the 2. If a species survives a change in environment ---> the change is not too rapid
As long as should be equivalent to 'if', so the latter should be correct.

nixy

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Re: "As long as" - Formal Logic?

Post by nixy » Fri Jun 05, 2020 1:11 pm

the thread you're responding to is 10 years old.

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LSATWiz.com

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Re: "As long as" - Formal Logic?

Post by LSATWiz.com » Fri Jun 05, 2020 4:26 pm

Non-restrictive durational knowledge is always a sufficient condition. When in doubt, make one variable New York and one variable the United States and ask yourself which way of reading the sentence makes sense.

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