how do you diagram this?

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how do you diagram this?

Postby lakers3peat » Fri Oct 08, 2010 11:40 pm

flawed reasoning question:

No member of Orchestra Google is a singer and a dancer. Since James and Paul are both members of Orchestra Google but neither is a dancer, it follows that both are singers.

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Re: how do you diagram this?

Postby typ3 » Fri Oct 08, 2010 11:49 pm

If MOG --> *S&D

If S&D ---> *MOG

J&P --> MOG

J&P ---> *D

Therefore J&P--> S

In my opinion you shouldn't need to diagram this flaw on a LR section. It's a pretty egregious error.

The stimulus says that if you're in the orchestra you can't sing and dance. However, just because you don't sing and dance doesn't mean you can't do a 3rd option. Perhaps you're in the orchestra and you play the Kazoo or Play the Electric washboard.

The stimulus says, because the two people aren't dancers they must be singers. We know this is a flaw because our original logical statement didn't say that members must be one or the other, rather they can't be both together.

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Re: how do you diagram this?

Postby Jeffort » Sat Oct 09, 2010 1:09 am

I reaffirm typ3's analysis.

The conditional premise establishes that ZERO individual members of the Google Orchestra group are both singers and dancers. Therefore the rule simply dictates that a member cannot be BOTH of those things, thus leaving open the possibility that members can be one or the other or NEITHER of those two things.

In short form logical talk the condition establishes NOT BOTH but does not dictate/require that a member has to be either (at least one) of the two. It allows a member to be neither a singer nor a dancer, which can be paraphrased as NOT EITHER/neither.

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Re: how do you diagram this?

Postby JazzOne » Sat Oct 09, 2010 2:31 am

False dichotomy flaw. Don't diagram it.


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Re: how do you diagram this?

Postby toolfan » Sat Oct 09, 2010 10:17 am

Yeh, this is something you'll have to pick up, quickly. don't waste time diagramming this.

No reversible error. judgment affirmed.

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