Necessary assumptions, treating them as "Must be True's" ? Forum

[flash21]

http://lsatblog.blogspot.ca/2012/01/neg ... tions.html

After reading this article by the LSAT Blog, I'm thinking this may be the best approach for me - it seems to simplify things more. So take the AC as something that must be true in order for the argument not to fall apart? NA's dont require you to link a bunch of things together like MBTs but I do think this might be a good way to look at things.

Thoughts? Advantages / disadvantages?

[Hotguy]

Funny, I treat them as MBT, but that's what I instinctively developed after lots of drilling. It does differentiate a bit in that the information isn't necessarily written in the stimulus.

[flash21]

I feel as though the wrong answer choices become much more apparent when using this

[Nova]

Makes sense. Sounds good

[iamgeorgebush]

This may be an effective approach for many, but they're not actually the exact same thing, and I'd argue that tackling necessary assumption questions in the same way that one tackles MBTs is ultimately not the best method.

All assumption questions (necessary, sufficient, strengthen, weaken, principle support, flaw, etc.) concern the reasoning of the argument and address some sort of gap in the reasoning. Personally, I have found that the best way to tackle these questions is to look for the gap in the reasoning, that gap that we need to fill in order to connect the premises to the conclusion. For necessary assumption questions, the answer choice must be true in order for the conclusion to follow from the premises, and this is not the same as a MBT, in which the credited AC must be true based on simple information (and there is no argument being made). While either approach to the question could lead you to the credited response, I believe that looking for the gap in the reasoning will lead you to the credited response more quickly and effectively than trying to negate every response. Remember, this is a timed test, and negation is time-consuming.

[bp shinners]

I actually disagree with Steve's statements* relating Necessary Assumption questions to MBT/Inference questions. A Necessary Assumption question can definitely bring in new information.

For instance, let's say I have this argument:
Worldwide piracy has increased in recent years.
Worldwide temperatures have increased in recent years.
______________________________________________
The rise in piracy has caused global temperatures to rise.

It's a correlation/causation fallacy - I'm assuming that since these two things go together, one causes the other. I'm also assuming that nothing else has caused this increase in global temperatures. So an answer choice that ruled out an alternative cause (depending on how it's phrased) could serve as an answer, even though that alternative cause was not mentioned specifically in the stimulus.

In fact, looking through my lesson books, a number of questions would qualify, to me, as bringing in information that is outside the stimulus (in other words, information that I would say would DQ it as an answer in a MBT/Inference question).

So, in a sentiment I'd never think I'd say, I'm in agreement with georgebush. Treating this as a MBT question is a good way to get them wrong.

*Based on what I know of Steve's experience, this is probably coming from me misunderstanding what he's trying to convey in that segment, not a misunderstanding on his part of the exam.

[BerkeleyMan5]

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