Q24 - Columnist: The amount of acidic

[dan]

24. (A)
Question type: Weaken the Conclusion
The conclusion of the argument is that we can expect a reduction of the negative consequences of acid rain, because the amount of acidic pollutants released into the air is decreasing. This argument requires a lot of assumptions (the acidic pollutants are not building up in the atmosphere, etc.) and the answer choices weaken the conclusion by attacking the assumptions.

(B) gives a reason why acid rain might not decrease even though acidic pollutants do.
(C) gives a reason why the premise will not continue to be true, therefore weakening the conclusion.
(D) gives a reason why the decrease in new acidic pollutants released may not reduce the effects of acid rain.
(E) gives another reason why the consequences may not get diminished.

Therefore, (A) is the correct answer. It does not provide information that weakens the author’s point.

[mrudula_2005]

I still don't understand how D weakens the argument. Even if the effects of acid rain are cumulative, the decrease in acidic pollutants has been going on for several decades so of course we can expect a decrease in the negative environmental effects of acid rain, right?

[haeaznboiyoung]

I think in terms of D, I read it as since the effects are cumulative, the full effects may not be reflected in current acid rain levels. So if for instance the rain level right now is 10%, it is considered safe. But since the effects are CUMULATIVE, next year they can add on to that 10% and have an acid rain level of 15%. So in that sense, cumulative rain levels can weaken the conclusion of expecting an overall decrease.

[mrudula_2005]

yeah - that's definitely it. thanks! since the effects of acid rain are cumulative, they can only increase. The decrease in acidic pollutants just adds a smaller amount to the total each year, but the overall negative environmental effects of acid rain still go up - all that's happened is that the rate of growth has slowed.

[LSAT-Chang]

Would (A) be wrong because it talks about the negative effects of "increased levels" when the argument is only talking about "decreased levels" of acids in the environment? So "out of scope"?

[jardinsouslapluie5]

I don't understand how (C) weakens...

[einuoa]

I too had some trouble with C, but here's my reasoning for it, if any LSAT geek can confirm/check this reasoning, I'd greatly appreciate it!

The stimulus is saying that the amount of acidic pollutants released into the air has decreased over the LAST SEVERAL DECADES, therefore we can EXPECT an overall decrease in negative environmental effects, presumably in the future. Answer choice C is saying that the current decrease will end, so there may be less of a likelihood that we can still expect an overall decrease in acid rain. It's not a very strong weakener in my opinion but it weakens nonetheless.

[christine.defenbaugh]

I too had some trouble with C, but here's my reasoning for it, if any LSAT geek can confirm/check this reasoning, I'd greatly appreciate it!

The stimulus is saying that the amount of acidic pollutants released into the air has decreased over the LAST SEVERAL DECADES, therefore we can EXPECT an overall decrease in negative environmental effects, presumably in the future. Answer choice C is saying that the current decrease will end, so there may be less of a likelihood that we can still expect an overall decrease in acid rain. It's not a very strong weakener in my opinion but it weakens nonetheless.

Great work einuoa!

What's really going on here is a temporal problem. As you pick up, the premise is about something that's happened in the past. And the conclusion goes on to predict something that will happen in the future as a result.

Arguments that make this kind of temporal shift are always vulnerable to attack on that basis! A better argument would hedge the conclusion a bit and say something like "If nothing changes, we can expect...."

Imagine if we said the Johnny has been saving his whole allowance every week for the past few months. Therefore, by Christmas, he'll have saved up a good chunk of change! Well, we'd have to assume that he'll continue to save instead of spend! If he decided to blow it all next week on games, then we wouldn't be able to conclude anything about what he'd have by Christmas.

That's how (C) sneaks in there to weaken the argument. If the premise will soon no longer be true, then it's a lot less likely to be able to support this prediction about the future!

Keep up the great work!

[jewels0602]

I was down to A and E, and I chose E.

I read the thread a few times over and I'm still not getting why A is correct, mostly because I'm unsure of what it means.

Can A be ruled solely on the basis that it's talking about increased level of acidic rain when we are only concerned about decreased amounts of acidic pollutants? (we can't determine the effects of these ecosystems once level of acidic pollutants start to decrease)

I'm unsure of what E is saying too and how it weakens the argument--so the minerals in soil are exhausted, but so what?

[sh854]

I am also wondering why A is correct. Please help.

[ohthatpatrick]

Question Type: Weaken EXCEPT

Task: Eliminate the four answer choices that Weaken

Argument Core:

P - Smaller amt of acidic pollutants released into air over last few decades

C - Going forward, we'll see a decrease in bad environmental effects of acid rain.

============

Our job in debating any conclusion begins with phrasing OUR side of the debate ... "We WON'T see a decrease in bad effects of acid rain"
or
"We'll see MORE bad environmental stuff from acid rain (or same amt)"

Let's get rid of the four answer choices that sound like BAD environmental stuff from acid rain is a-comin'.

(A) This sounds like the opposite of what we want (which is why it's the answer). This sounds good --- ecosystems have figured out a way to protect themselves from bad acid rain stuff.

Let's see how the four other choices DO make it sound like BAD environmental stuff from acid rain is a-comin'.

(B) We have stuff that NEUTRALIZES acid, but we're NOT using it as much anymore.
(bad -- we're not neutralizing acid as much as we used to)

(C) Pretty soon, countries are gonna start making more acidic pollutants again.
(bad -- increased levels of acidic pollutants are a-comin')

(D) Bad acid rain stuff is apparently NOT something that disappears once you stop the acid rain. It's like you have a permanent bank account of damage in the ground, and every time you get more acid rain, it only ADDS to the bank account of damage. So we're adding less each year to the account than we used to, but were still adding damage (bad).

(E) Some ecosystems used to have a built in mineral shield that protected them from bad acid rain stuff. However, that shield has been depleted. If their shields are now down, then acid rain can start inflicting its bad stuff.

[maria487]

In a sense, couldn't you say that (A) is actually weakening in that it provides an alternative cause for the predicted effect given in the conclusion?


The stimulus says: Acidic pollution decreased --> Expected decrease in negative environmental effects of acid rain.

If you then give another reason why you can expect a decrease in the negative environmental effects of acid rain, as (A) does--sophisticated mechanisms that reduce negative effects of acid (note: this does not say acid rain, so I'm interested how this plays into the argument), would that not weaken?

[ohthatpatrick]

Say that this was my argument:

The Prius gets 50 miles per gallon. Thus, I think you would enjoy owning a Prius.

Would this idea strengthen or weaken?
The Prius has smooth handling and ample cargo space
(This post response is brought to you by Toyota)

Providing MORE reasons to believe that I would enjoy having a Prius strengthens the argument. It makes the conclusion more plausible.

=======

The alternative-explanation template you're citing works like this:

PREMISE: a puzzling phenomenon or statistical anomaly
CONC: a potential explanation for that

Here, an alternative explanation weakens the Conclusion / Argument. We're always judging the truth value of the conclusion. So when you propose an alternative explanation, you make it seem less likely that the conclusion's explanation is the valid one.

Meanwhile, what THIS argument gave was
PREMISE: statistical phenomenon
CONC: a prediction based on that phenomenon

We're judging the truth value of the prediction. WILL that prediction come true? The more reasons you give me for thinking the prediction will come true, the more likely it is that the prediction in the conclusion is valid.

Remember, the four answers we're eliminating make it seem like we WON'T see a decrease in negative effects of acid rain.

You could probably rectify your thinking on (A) by simply switching from calling it an "alternative" reason for believing the conclusion to calling it an "additional" reason to believe the conclusion.

Hope this helps.

[nexus_1]

[quote="ohthatpatrick"]Say that this was my argument:

The Prius gets 50 miles per gallon. Thus, I think you would enjoy owning a Prius.

Would this idea strengthen or weaken?
The Prius has smooth handling and ample cargo space
(This post response is brought to you by Toyota)

Providing MORE reasons to believe that I would enjoy having a Prius strengthens the argument. It makes the conclusion more plausible.

=======


hi,ohthatpatrick, i don't think your example strengthen the ARGUMENT. I think your example just strengthen the CONCLUSION. I cannot understand why this strengthen the argument and I'm really puzzle about that. Could you please explain in details?

[tommywallach]

Technically, if something strengthens the conclusion, it does strengthen the argument, as the argument has only been made to reach the conclusion. That said, I still think this does strengthen the argument as a whole anyway.

-t

[roflcoptersoisoi]

In a sense, couldn't you say that (A) is actually weakening in that it provides an alternative cause for the predicted effect given in the conclusion?


The stimulus says: Acidic pollution decreased --> Expected decrease in negative environmental effects of acid rain.

If you then give another reason why you can expect a decrease in the negative environmental effects of acid rain, as (A) does--sophisticated mechanisms that reduce negative effects of acid (note: this does not say acid rain, so I'm interested how this plays into the argument), would that not weaken?

Not necessarily, because the argument doesn't posit that the only way we could have a decrease in the negative environmental effects of acid rain is through the decrease in acidic pollutants.