Weaken Causality Question

[seychelles1718]

Hi

When we have the causality (A: cause --> B: effect), the LSAT assumes A (cause) is THE ONLY cause for the effect, B.
But in some weaken questions that ask us to undermine the causality by bringing up the possibility of an alternative cause, the wrong answer choices state "most of B were due to C (an alternative cause)." If the causality means A is THE ONLY cause for B, why are those answer choices incorrect? If "most" or "some" effects were due to some reasons other than A, it attacks the assumption that A is THE ONLY cause.

Can someone please help me with this?

Thanks

[ohthatpatrick]

I'm not sure where you got that first idea, but that seems to be the source of your confusion:
When we have the causality (A: cause --> B: effect), the LSAT assumes A (cause) is THE ONLY cause for the effect, B.

That is incorrect.

If I say "tickling my armpits causes me to laugh", I am in no way assuming that "tickling my armpits is THE ONLY way to cause me to laugh". Thinking that way would be committing a Sufficient vs. Necessary flaw.

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The second thing you're referring to sounds like a completely separate scenario.

If an author presents a puzzling phenomenon or statistic and then concludes a causal explanation, then we don't "have" causality.
We only "have" the facts of the evidence. We only know the puzzling phenomenon/statistic.

The explanation the author presents in the conclusion is not something we accept as fact. The author sounds certain of her hypothesis, but it's her CERTAINTY we're attacking! We are weakening her argument by either showing that her hypothesis is an implausible one (not very common - this is normally done by showing the presence of the supposed cause going along with the absence of the supposed effect), or by supplying an alternative explanation for the same background fact (this is way more common).

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I think you're just getting jumbled by different contexts of causality.

If the PREMISES give us causality, then the AUTHOR will normally commit the mistake of thinking one possible cause is the only cause.

If the PREMISES just give us a phenomenon / statistic / correlation, and the author's conclusion picks one possible explanation as CLEARLY "the" explanation, then we can strengthen/weaken the author's hypothesis by either addressing its plausibility or by considering alternative explanations for the same background phenomenon / statistic / correlation.

[beanieb784]

Confused about the first idea too.
I got the first idea from http://www.powerscore.com/lsat/content/ ... erpt_2.pdf

On Page 203, the second paragraph states that "When an LSAT speaker concludes that one occurrence caused another, that speaker also assumes that the stated cause is the only possible cause of the effect and that consequently the stated cause will always produce the effect. "

Does that mean when we have causality "A causes B" on the LSAT (not in the real world), the LSAT assumes that A is both the sufficient (always produce) and the necessary (the only possible cause) cause of B?

Thanks!

[ohthatpatrick]

No, heavens no.

It's just a weird, badly written sentence. I can't imagine that Powerscore commits itself to backing that up for all causal arguments. That would be cray.

You could say something closer to
"When an author concludes that one occurrence caused another, she assumes that HER causal interpretation is plausible and fails to consider any other causal interpretation that would be at least as likely."