Trouble with Sufficient Assumptions

whiteness
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Trouble with Sufficient Assumptions

Postby whiteness » Sun May 20, 2012 10:31 pm

Sufficient Assumption Questions are one of my weak points in LR and I ran out of those types of questions from old pt's and don't want to go into my newer pt's that I am saving for the weeks leading up to the june test. Any advice on how to get better at these?

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Br3v
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Re: Trouble with Sufficient Assumptions

Postby Br3v » Sun May 20, 2012 10:42 pm

whiteness wrote:Sufficient Assumption Questions are one of my weak points in LR and I ran out of those types of questions from old pt's and don't want to go into my newer pt's that I am saving for the weeks leading up to the june test. Any advice on how to get better at these?


Doing pt questions is only real way. If you don't have it, read powerscore logical reasoning bible

bp shinners
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Re: Trouble with Sufficient Assumptions

Postby bp shinners » Mon May 21, 2012 2:47 pm

Do you have a strategy for them? They usually fall into one of two categories (other than the diagrammable/non-diagrammable dichotomy).

The first is when there's a concept mentioned in the conclusion that hasn't yet shown up in a premise. If that's the case, eliminate any answer choice that doesn't mention that concept. It can't be a sufficient assumption for the argument. Now, you should have 2-3 answer left. Of those, 1 probably lacks a concept from a premise - get rid of it. The two that are left are usually converse of each other. If the conclusion has the new concept relying on the determination of another concept, pick the answer that does the same (premise concept->conclusion concept). Same with vice versa. These are the most common - new term in conclusion that has to be connected.

The second is where every concept in the conclusion shows up in a premise, and these are harder. You're going to end up with a gap in your premises - the concepts will all be there, but two of them that need to be connected by a statement won't be. The correct answer is the one that includes both concepts in this statement.

Yes, this is easier to do when you diagram. However, the non-diagrammable ones have the same process, it's just sometimes a little tougher to see where you have to make the connection.

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sundance95
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Re: Trouble with Sufficient Assumptions

Postby sundance95 » Mon May 21, 2012 2:56 pm

whiteness wrote:Sufficient Assumption Questions are one of my weak points in LR and I ran out of those types of questions from old pt's and don't want to go into my newer pt's that I am saving for the weeks leading up to the june test. Any advice on how to get better at these?

A tip that really helped me on these when I was studying for the LSAT; if the conclusion contains any element of "should" or "ought to", then there needs to be a premise that establishes what "should" or "ought to" happen.

Rough example from the top of my head:

If I eat out, I will spend extra money. If I spend extra money, I will not be able to pay my rent. Therefore I should not eat out.

An example of an answer that would provide a sufficient assumption is "I should not do things that will cause me to not be able to pay my rent."

Not all sufficient assumption questions are "should" questions, but they come up frequently and once you start to key in on "should" you'll be able to quickly answers the "should" Qs.

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Campagnolo
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Re: Trouble with Sufficient Assumptions

Postby Campagnolo » Mon May 21, 2012 3:00 pm

Okay, so you've got your basic A ---> B thing down, right?

Well, a sufficient assumption is something that can replace A and still have the relationship be valid. (And a Necessary Assumption would be something that could replace B, if that helps.)

Now, here's an example. If there are human beings, there is oxygen present.

You could diagram it like this: HB ---> O

Now if we want a sufficient assumption, we have to think about how to replace HB in the relationship. Here are some things that would work: skyscrapers, language, conceptual thought, music, art. Any of these things can replace HB as the sufficient condition, allowing us to complete the argument.

Does that help at all?

Edit: I thought I would give some examples of necessary assumptions in the example above. Any of the following would work: water, nitrogen, a certain temperature range, DNA, carbohydrates, proteins, etc., etc. There will almost always be more necessary assumptions possible than sufficient assumptions. That is because there is a bevy of things required for human life. There are, by contrast, very few things that make human beings truly distinct from every other creature.

bruss
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Re: Trouble with Sufficient Assumptions

Postby bruss » Mon May 21, 2012 9:47 pm

Superprep and Lrb ftw.

Great examples guys.

whiteness
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Joined: Wed Apr 25, 2012 3:49 pm

Re: Trouble with Sufficient Assumptions

Postby whiteness » Tue May 22, 2012 2:02 pm

Thanks everyone




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