Logical Reasoning

PT155 · S4 · Q18 Certain changes in North American

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Certain changes in North American residential architecture after World War II are attributable mainly to the increased availability and affordability of air-conditioning.

Conclusion

The reason residential architecture changed (fewer high ceilings and thick walls) after WWII is the increased usage of A/C.

Evidence

Soon after WWII, many builders found that houses with A/C that also lacked the high ceilings and thick walls that were previously used to keep houses cool generally sold well.

Evaluate

The conclusion is this sort of claim: "X is attributable mainly to Y".

In other words, Y is the main cause of X. Since the author is positing causality in the conclusion, we can use our Curious Fact / Explanation template if we'd like.

Curious Fact Why did residential architecture change after WWII (fewer high ceilings / thick walls)?

Author's Story Builders found that houses that kept cool using A/C, rather than high ceilings / thick walls, were generally selling well (so they made more houses with A/C and fewer with high ceilings / thick walls).

We can affect these arguments in two ways: - some alternative story for why architecture changed - something affecting the plausibility of the author's story

Goal

Since this is Weaken, we would either want a different way to explain why the architecture changed (interior design standards changed? construction styles changed?), or we need to diminish the plausibility of the story where builders look at A/C houses that are selling well and decide to make more of those and less of the kind that has high ceilings / thick walls.

18.

Which one of the following, if true, most seriously weakens the argument?

High ceilings and thick walls
No Impact
This tells us a timeless truth about high ceilings and thick walls. Since we're trying to assess a change that happened after WWII, the answer will probably deal with that time frame specifically. This detail about high ceilings and thick walls doesn't help us assess whether architecture moved away from this style because of A/C or some other reason.
3% picked this
Thin-walled, low-ceilinged houses are more
No Impact
Again, like (A), this answer doesn't say anything about the specific time period we're investigating. This answer essentially leads us to think that thick walls and high ceilings are better in the hot of summer and in the cold of winter. So why did we move away from that? Not sure. This answer doesn't help solve that mystery.
5% picked this
Correct
Houses with low ceilings and
Why this is right
Well, I am pretty opposed to this question overall, so take this explanation with a grain of salt. This answer is trying to take the form of a (No Cause, Effect) plausibility weakener. When it uses the past tense "were", we're apparently supposed to assume that it's talking about the period right after WWII. i.e., "Hey author, if A/C was really the cause of moving towards lower ceilings and thinner walls, then how do you explain that these houses were prevalent even where there was no demand for A/C?" (The author could simply say, "I just said they were the main cause. There were lower ceilings and thinner walls in areas w/o demand for A/C for some of those secondary reasons, such as they're cheaper to build and you can build more floors with lower ceilings.") This answer would only have the power the test writers are wanting it to have if it had said "houses with low ceilings and thin walls were just as prevalent where there's no demand for A/C". Or it would be better if it said, "Houses with low ceilings and thin walls were prevalent in new constructions after WWII even where there was no demand for A/C." Otherwise, it's really an answer with no impact. "Prevalent" just means "common / not rare". I'm sure that many styles of house are prevalent in all places. That doesn't mean they're desired or newly constructed or trending. Houses with stucco painted ceilings are very prevalent right now (because that was a fad in the 70s), but modern builders don't make new homes in that style. So even though modern builders have made a certain change in terms of how they paint ceilings in residential architecture, that old style is still prevalent in existing houses. Sigh, oh well. We can't fight city hall. I don't know why they think this answer is better than (E), which introduces an alternate explanation. But they think that this answer calls into question the plausibility of the author's explanation by saying that the observed effect (thinner walls / lower ceilings) was present even in areas not affected by the supposed cause (demand for A/C).
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
61% picked this
Thin walls allow cool, air-conditioned
No Impact
One might interpret this as weakening in the sense of, "This story makes no sense! You're saying they switched to thin walls because of A/C. Thin walls actually let air-conditioned air escape more easily!" But we already knew that. We know that high ceilings and thick walls are traditionally how houses insulated cold air during the hot months, so we already know that any house with A/C and lacking thick walls is going to be letting more air escape than a thick-walled, more insulated house would. The gist was that we were able to switch to thinner walls because the A/C was making it so that we didn't need to rely on thick walls to stay cool.
12% picked this
Soon after World War II,
Unclear Impact
I would have picked this answer, as it suggests an alternate explanation for why residential architecture changed soon after WWII (you don't need high ceilings and thick walls to keep the inside cool during hot months if you most houses now have new insulating technology). I don't really know how to tell you why it's wrong. The best I can come up with is that LSAC thinks that because the author said "certain changes are attributable mainly to the increased usage of A/C" that we're not really weakening the argument to pose an additional reason why builders made the switch. Or it's possible that LSAC thinks of "thermal-insulation" technology as something that could be a solution for keeping homes warm but not a solution for keeping homes cool. (the problem with that is that anyone who lives in a hot desert climate knows that you open the doors and windows at night to let the cool night air in, and then you try to keep that cool air in your house throughout the hot day by keeping those doors and windows shut. Thermal insulation would seemingly help you to "protect" the cold air you let in at night, but perhaps that's too weird of an example for LSAC and they thought this answer would only provide a solution for heating homes, not cooling them).
18% picked this

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