#9 - Records from 1850 to 1900 show that in a certain

[Administrator]

Complete Question Explanation

Method of Reasoning—CE. The correct answer choice is (A)

Here, the author looks to historical records for evidence about the relationship between food availability and newborn health. A review of records from 1850 to 1900 details a correlation between birth weights and the success of crops the year earlier. From this correlation, the author concludes that there is a causal connection between the amount of food available to the mother during her pregnancy and the health of the newborn. This relationship can be diagrammed as:


more food = more food available to the mother during pregnancy
better health = better health of the newborn at birth

Cause Effect

more food better health


It should come as no surprise that this causal conclusion is flawed. First, the only support for the conclusion is a correlation, which we know cannot provide proper support for a valid causal conclusion. This is true even when the conclusion is moderated, as is the conclusion here, that newborn health depends to a large extent on food available to the mother.

In addition to that flaw, the terms in the argument shifted from the premise to the conclusion. The premise mentioned birth weights while the conclusion talked about newborn health. Also, the author gave evidence about crop success, yet reached a conclusion about food availability. While certainly these term pairings are related, they are not synonymous. As a matter of common sense, we can say that birth weight is just one factor having to do with newborn health, and crop success is just one factor in food availability.

The question stem tells us that this is a Method of Reasoning question. Our prephrase is that this was a flawed, causal argument, in which the causal conclusion was supported only by evidence of a correlation, and the terms shifted from the premise to the conclusion.

Note that the question stem does not identify this argument as flawed. While a Flaw in the Reasoning question will certainly display flawed argumentation, the conclusion in a Method of Reasoning question may be either valid or flawed.

Answer choice (A): This is the correct answer choice, because it describes both flaws. The “correlation between two phenomena” refers to the correlation between crop success and birth weights, while the causally connected phenomena are food availability and newborn health.

Answer choice (B): This is a Half Right, Half Wrong answer choice. Although the first part of this answer accurately refers to the correlation between crop success and birth weight, the second part of the answer mistakenly states that food availability was cited as the sole cause of newborn health. Rather the conclusion was that newborn health depends to a large extent on food availability.

Answer choice (C): This answer choice is attractive, because it properly describes the historical nature of the evidence and the present tense language of the conclusion. However, the conclusion was not that the historical correlation continues, but rather that the causal relationship remains the case.

Answer choice (D): The “two phenomena” observed in historical records were crop success and birth weights. The argument did not infer that these two phenomena resulted from a common cause.

Answer choice (E): Although the author did infer the existence of a causal connection, the evidence was a correlation, not a separate causal relationship.

[jbacal]

This is a method of reasoning question that I'm having a hard time breaking down. I chose answer B, but the correct answer is A. Can anyone provide an explanation?

[Lucas Moreau]

Hello, jbacal,

I can see why you might be confused between B and A - they're really quite similar. The difference is that B talks about a sole cause, which the stimulus does not assert (the stimulus says "depends to a large extent on"). A states that a causal connection is asserted, which is true, it's just not claimed to be the only cause.

Hope that helps,
Lucas Moreau

[MikeRov25]

Hello,

I was confused by A, is the first two phenomena "babies birth weights each year varied with the success of the previous years crops" and the second two phenomena "the more successful the crops, the higher the birth weights"?

Also does the line "this indicates that the health of newborn depends...", make the causal argument?

Thanks!

[Jonathan Evans]

MikeRov,

This is a kind of funny Method of Reasoning question because the argument is ridiculously flawed, but the approach doesn't change. Describe the parts of the argument in abstract terms:

An observed correlation between two phenomena is offered as evidence of a causal relationship between two other phenomena.

The first two phenomena are:

"crop success" and "babies' birth weights"

The second two phenomena are:

"amount of food available to mothers during pregnancy" and "babies' health"

It's a silly argument, but sometimes the more flawed an argument is, the harder it is to wrap your head around it.

[cardinal2017]

Hi, I'm just confused why the conclusion is a causal argument.

I could wrap my head around anything about this question but the causality of the conclusion.

The conclusion describes a conditional relationship with the verb 'depends on' but I wasn't so sure if the phrase 'depend(s) on' can be so strong as to allow the conclusion to be causal.

I thought just the phrasal verb 'depends on' is not enough to make the conclusion in question causal. It basically indicates 'necessary condition,' to my knowledge. Anyone can explain how 'depend on' makes a causal conclusion here?

Thanks in advance!

[Jonathan Evans]

Great question, Cardinal! There is certainly a great degree of overlap between the concepts of conditional reasoning and causality. In fact, one of the first questions we introduce during the Causality unity in our PowerScore LSAT course has elements of both conditional reasoning and causality (Question 5 from LR Section 3 on PrepTest 40).

For instance, consider the following example:

• If I get enough sleep, I'll do well on my presentation tomorrow.

This statement could certainly be represented conditionally:

• Enough sleep Good presentation

But it also contains a degree of causal reasoning. It is reasonable to assume that adequate sleep contributes in part to a good presentation.

One of the hardest concepts to convey with respect to conditional reasoning is that formally, material conditionals are unrelated to causality.

For instance, consider this statement:

• If I eat an apple, New York is a big city.

This nonsensical statement is a perfectly valid conditional, however disconnected from reality it may be.

To make a long story short, "depends on" as used here is both conditional and causal. Please follow up with further questions!

[Bruin96]

Initially, I crossed out answer choice A because I did not see a causal connection. I saw the conditional relationship but I did not find it be causally related. However, after reading the explanation I see where I had gone wrong.

If possible, can someone please send links for any information about the differences between Conditionality & Causal relationships. Also, is correlation a form of conditionality? I am a bit confused.

[KelseyWoods]

Hi Bruin96!

There is a difference between correlations and conditional relationships. A correlation just means two things are related in some way (but based on a correlation, we don't know if it's a causal relationship, a conditional relationship, etc.), whereas conditionals are a very specific type of relationship in which one thing indicates another.

Here are some helpful links about the differences between conditional and causal reasoning:
Conditionality vs. Causality: https://blog.powerscore.com/lsat/powers ... he-day-12/
LR Bible Excerpt that includes discussion of the differences between conditional and causal reasoning: https://www.powerscore.com/lsat/help/co ... xcerpt.pdf
Correlations and Causal Reasoning: https://www.powerscore.com/lsat/help/lr ... soning.cfm

Hope this helps!

Best,
Kelsey

[cornflakes]

Hi Powerscore,

I selected C for this one because I was immediately drawn in by the flawed reasoning of "this thing happened/was observed in a certain period of time, so it must always hold." The conclusion seems to extrapolate a general axiom from the records stated in the premise - that newborn health depends (is effected) by the amount of food available (the cause) to the mother during pregnancy.

Looking back, I can understand why A does accurately describe two elements of how the argument proceeds - it infers from a claimed correlation between two phenomena (crop success and birth weight) that two other phenomena (newborn health and availability of food to mothers during pregnancy) are casually connected to each other.

In hindsight, I think I did vaguely detect the correlation/causation flaw, but was very fixated on the time period extrapolation idea. Because of this, I did not think much of the word salad substitution that the writers slipped in and just designated them as synonymous proxies of each other. By this, I am referring to the crop success ~ food availability and the birth weight ~ newborn health. While each former item in these examples definitely refers to a component of the latter, it only represents a part of the latter, and not the entire piece.

I believe it was this error that truly cost me here, because under my synonymous proxy assumption, A and C looked similarly attractive. When taking into account this modified understanding, A describes the proxy inconsistency error accurately by referring to the "other phenomena", while C treats both items as the same. You could also argue that C fails to acknowledge the author's elevation of the correlation to a causal relationship, but I felt like by stating the newborn health is casually impacted by food availability, the author is still stating that a correlation still exists, even if they did so by stating a general axiom (its just not THE correlation we care about, which is newborn health and food availability).

Let me know if you feel like C can be eliminated for reasons other than what I outline here (the proxy synonym error). I had a lot of trouble on this one.

Thanks.