Q25 - Numerous studies have demonstrated

[ohthatpatrick]

Question Type:
Weaken (looks like Flaw, but all answers are prefaced by "overlooks the possibility")

Stimulus Breakdown:
Conclusion: Not enough fiber causes colon cancer and enough fiber prevents it.
Evidence: Several studies show correlation between high fiber and low incidence of colon cancer.
(Western countries have more colon cancer, less fiber than non-Western countries)
(Scandinavia: higher colon cancer rates, low rates of eating cereals, which have fiber)

Answer Anticipation:
Whenever we're dealing with Causal Explanation conclusions, we have two prongs of attack:
1. Are there OTHER WAYS to explain the premise?
2. Is the Conclusion plausible?

So we're looking for OTHER ways to explain the correlation between colon cancer / fiber intake in Western vs. non-Western or to explain the correlation between colon cancer / cereal intake in Scandinavia.

Or, we just need counterexamples/ideas that weaken the plausibility that fiber intake / colon cancer have this very strong inverse causality.

Correct Answer:
E

Answer Choice Analysis:
(A) This does nothing, since it doesn't tell us which countries or what the connection to colon cancer is.

(B) This strengthens the plausibility that high fiber might help to lower risk of colon cancer.

(C) We don't care about the difficulty of eating fiber; we only care about whether it has a causal connection to colon cancer.

(D) This doesn't do anything. Even if they are cancer-fighting to different degrees, they're both still cancer fighting, which is strengthening the argument.

(E) Yes! This gives us an OTHER WAY to explain the correlations between fiber and colon cancer. It's not that the FIBER was reducing the risk of cancer, it was some OTHER ingredient in the fibrous foods people were eating that was reducing the risk of colon cancer.

Takeaway/Pattern: When an author goes from a correlation between X and Y to a causal conclusion that "X caused Y', the most common way to weaken the argument is to say that there is really some third factor, Z, that is the causal agent. Z might be causing both X and Y, or Z might be accompanying X and causing Y.

#officialexplanation

[niwallace]

I'm confused, isn't D just as valid an answer as E ?

[ohthatpatrick]

This argument is, naturally, Ye Olde "Correlation --> Causality", one of the most tried and true LSAT reasoning patterns.

There are a handful of premises, each one a correlation showing low-fiber and high-colon cancer going hand in hand (or high-fiber / low-colon cancer).

Correlations certainly strengthen a picture of causal influence, but they don't PROVE such a thing, as our LSAT authors love to believe.

So the conclusion is way too definitively worded.

On a Flaw question, it would suffice to say that this argument is vulnerable to criticism because it "treats two factors that merely coincide as though one causes the other".

On Strengthen/Weaken questions, we normally get three types of answers:
- dealing with the possibility of Reverse Causality (could it be that having colon cancer causes you to eat less fiber?)
- dealing with the possibility of Alternative Explanations (could something else be causing the colon cancer for those who are eating low-fiber or preventing the colon cancer for those who are eating high-fiber?)
- more correlation evidence (are there any cases in which high fiber eaters have high colon cancer rates)

The phrase "overlooks the possibility" on Flaw questions basically transforms an answer choice into a Weaken answer choice. I analyze them by thinking, "if true, would it Weaken".

Let's look at (D).

If it's true that the fiber in fruits and veggies has more/less cancer-fighting properties than the fiber in cereal, does that Weaken the argument?

I don't see why it would. Who cares whether cereal fights cancer better than fruit or fruit fights cancer better than cereal? The issue of this conclusion is simply whether FIBER actually fights/causes colon cancer.

All the argument claims is that fruit, veggies, and cereal are all high in fiber. That doesn't mean they are identical in fiber content or cancer-fighting properties, so (D) wouldn't go against anything the author said or needed to believe.

If (E) were true, if fibrous foods actually had some other substance that tends to prevent colon cancer, THAT would weaken the argument. That provides an alternative explanation. We can doubt the idea that FIBER actually prevents cancer because now we have the possibility that a different ingredient accounts for these cancer correlations.

(D) doesn't give us a way to doubt that fiber prevents cancer. It only lets us rank fruits/veggies as being better/worse cancer fighters than cereal.

Let me know if this fails to address your concern or interpretation of (D).

[valmir_merkaj]

I chose D because if cereal fiber has a cancer-fighting property of 0, then the second premise would be just a mere correlation and would not support the conclusion at all. The conclusion is resting on this premise and in this scenario would be faulty because of it.

I also see why E is correct.

[lizchung74]

The main reason D is different from E is because it says CANCER-fighting properties instead of COLON cancer.

D tricks you by talking about the fiber in fruits, vegetables, cereal since those are mentioned in the stimulus but ultimately, it doesn't matter if these prevents other types of cancer, it's COLON cancer that is in question.
LSATs seem to do this often. Hope that helps!