Logical Opposities

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msw099

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Logical Opposities

Postby msw099 » Mon Jun 14, 2010 4:33 pm

Hi All:

What is the logical opposite of "At Least Some" and "At Least One?" I figured that these were the same but a book is telling me otherwise.

I thought that the logical opposite for both was none. Is this correct?

This will help me on negating some necessary assumptions.

Thank you!

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cinefile 17

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Re: Logical Opposities

Postby cinefile 17 » Mon Jun 14, 2010 4:37 pm

I would agree that these two phrases are logically the same and that the logical opposite of both would be none.

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nonamebreakdown

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Re: Logical Opposities

Postby nonamebreakdown » Mon Jun 14, 2010 4:39 pm

"Some"/"At least some" = 1 or more

negation is none.

example: negation of "Some people like the color blue" is "No one likes the color blue."

cubswin

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Re: Logical Opposities

Postby cubswin » Mon Jun 14, 2010 4:40 pm

msw099 wrote:Hi All:

What is the logical opposite of "At Least Some" and "At Least One?" I figured that these were the same but a book is telling me otherwise.

I thought that the logical opposite for both was none. Is this correct?

This will help me on negating some necessary assumptions.

Thank you!


Yes, you are correct. The opposite of "At least one" is none, and "some" is an indefinite quantity, so on the LSAT assume that it means "at least one."

msw099

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Re: Logical Opposities

Postby msw099 » Mon Jun 14, 2010 4:41 pm

That's what I thought, thanks.

msw099

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Re: Logical Opposities

Postby msw099 » Mon Jun 14, 2010 4:43 pm

What about the logical opposite to "usually and Most?" Is it "Not usually and not most or less than half?"

Thanks again.

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iamcutdacheck

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Re: Logical Opposities

Postby iamcutdacheck » Tue Jun 15, 2010 3:24 am

msw099 wrote:What about the logical opposite to "usually and Most?" Is it "Not usually and not most or less than half?"

Thanks again.

unusually or least

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youpiiz

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Re: Logical Opposities

Postby youpiiz » Tue Jun 15, 2010 3:29 am

freedom fries and petain poutines

cubswin

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Re: Logical Opposities

Postby cubswin » Wed Jun 16, 2010 12:18 pm

msw099 wrote:What about the logical opposite to "usually and Most?" Is it "Not usually and not most or less than half?"

Thanks again.


Well, most means more than half, so the opposite would be less than half. I don't think "usually" is used a quantity statement all that often. I don't know whether to assume it means "Most of the time" or if it's not specific enough and should just be taken to mean "some."

bp colin

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Re: Logical Opposities

Postby bp colin » Wed Jun 16, 2010 12:28 pm

cubswin wrote:Well, most means more than half, so the opposite would be less than half.


Actually, the opposite would be "not more than half." Which doesn't actually have to mean less than half; it means half or less. The LSAT's required you to make that inference a few times.

cubswin

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Re: Logical Opposities

Postby cubswin » Sat Jun 19, 2010 1:15 pm

bp colin wrote:
cubswin wrote:Well, most means more than half, so the opposite would be less than half.


Actually, the opposite would be "not more than half." Which doesn't actually have to mean less than half; it means half or less. The LSAT's required you to make that inference a few times.


Damn, you are right.



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