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LR Bible Problem!

LSAT Leader
Posts: 26
Joined: Sat Sep 15, 2018 10:37 am
Points: 27


I was having a problem with the bible's explanation of cause and effect. Specifically, and I could be wrong here, it seems they equate "x causes y" with "only x causes y". I don't seem to agree with this!

Let's say you conclude smoking causes cancer. You wouldn't be able to poke a hole in that conclusion by saying "Cases of cancer (the effect) have been shown in non smokers" (i.e. effect produced without the cause), and you wouldn't be able to say that because it wasn't stated that smoking is the only thing that causes cancer.

However, the following hole could be poked: There have been smokers who didn't get cancer (a cause without the effect), which demonstrates that, at best, smoking can cause cancer, but the statement "smoking causes cancer" would have doubt cast upon it.

Overall, I don't think that x causes y implies the author thinks that only x causes y or even that x causes only y.

Thank you!!
Adam Tyson
PowerScore Staff
PowerScore Staff
Posts: 2667
Joined: Thu Apr 14, 2011 5:01 pm
Points: 2,480

You're certainly correct that in the real world, we allow for multiple causes. Also, on the LSAT, there are many arguments wherein the author claims that one thing is a cause or a factor in bringing about some effect, and in those cases the author is allowing for other causal factors, and we treat them less harshly.

However, it is useful when approaching LSAT questions to react as if the author of an unqualified causal claim - X causes y, for example - believes that it is the only cause. That's why the introduction of an alternate cause weakens (but does not necessarily disprove) the causal claim. You should approach these questions as if the authors are unreasonable in that way, for when you do so you will find that they are much easier and there is little room for doubt in your selection of the correct answer. If the cause happens and the effect does not, that weakens; if the effect happens and the cause does not, that also weakens; etc.

Our position isn't about real causal arguments. It is about the best strategy for attacking LSAT causal arguments. On the LSAT, if an author concludes that smoking causes cancer, to use your example, then an answer that says some non-smokers also get cancer does indeed poke a hole in the argument by introducing some doubt about the original claim. Sure, smoking could be one of several causes, but it could also be that smoking has nothing to do with it, and there is some other cause common to both smokers and non-smokers.

When looking to weaken an argument, the standard is very, VERY low. Just raise some doubt, and that is enough. An effect without the purported cause does at least that much.
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
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