Q19 - The conventional process for tanning

[ohthatpatrick]

Question Type:
Necessary Assumption

Stimulus Breakdown:
Conclusion: If you use biological catalysts, tanning leather will be cheaper.
Evidence: A big part of the cost of tanning is waste disposal. If you use biological catalysts, you get 20% less waste. In all other senses, using biological catalysts costs about the same as conventional chemicals.

Answer Anticipation:
We're debating whether it would really be CHEAPER if we used biological catalysts. All we know is that there would be 20% less waste. So we're assuming that "20% less waste = cheaper". How could it be 20% less waste but still more expensive? Maybe it's using biological catalysts makes the waste a more volatile chemical (like nuclear waste or biohazard waste) so it has to be disposed of in a more costly way. The author is assuming that it WOULDN'T have to be dispoed of in a more costly way than that for conventional chemicals.

Correct Answer:
D

Answer Choice Analysis:
(A) Out of scope. The author never touches on "quality". We only care about overall cost.

(B) Irrelevant. Has that Premise Booster feel. We already know that cost of USING the chemicals is roughly the same. So why does the author need biological catalysts to cost less by weight? He'd be perfectly content if they cost the same. The author thinks our cost savings are coming from the fact that there's 20% less waste in the end.

(C) Out of scope. The author doesn't need to assume that the cost effectiveness of biologial catalysts is a RECENT DEVELOPMENT made possible by NEW TECHNOLOGICAL INNOVATIONS.

(D) Yes! If we negate this, we get that "disposing of the biological catalysts costs signifcantly more than disposing of conventional chemicals". This makes it possible that 20% less in volume could still be equal or greater in cost.

(E) Out of scope. We don't need to say anything specific about labor costs, because the author has already told us that, other than disposal, the costs of biological vs. conventional balance out to be about the same.

Takeaway/Pattern: About half the correct answers to Necessary Assumption have the "ruling out" feel of "_____ does NOT cost significantly more than ____". These answers are also very easy to negate, since we can simply remove the 'not'.

#officialexplanation

[cdjmarmon]

I was between D and E and picked E, which was wrong.

My issue here is I tried the denial test on each answer and each one would destroy the arguement.

However, I think I can slightly see how E is irrelevant becuase the argument says tanning using the biological catalyst process costs about the same as using than the conventional process. So, I would assume that when they are talking about the "process" they are including the labor costs associated with that process.

Anyway, I would appreciate some clarity on my assumption. Also, Im very curious how two answers, when negated, can destroy the argument but only one is right and the other is out of scope.

[timmydoeslsat]

I agree with you that labor costs would be considered as part of the process. We really are told that if you leave out the waste disposal aspect, that the two ways of doing this tanning are about the same.

So I would immediately be skeptical of (E). Any greater? We can have something be slightly greater with no problem.

This argument comes down to the idea of producing less waste vs cost of waste disposal.

We haven't talked about cost when dealing with disposing of these two types of wastes.

Answer choice D gives us that classic LSAT idea of significantly.

What if it were true that disposing the biological ones were significantly more expensive than the chemical ones?

You would have an argument that needs to be disposed of immediately.

We know that waste disposal is a substantial part of the overall cost of tanning. These two processes are the same basically when you do not consider the waste disposal.

Throw in the idea that the biological one is significantly more expensive than the other. This argument is waste disposal material at that point.

[cdjmarmon]

Got it. Thank you.

I am also curious of one more thing though. The negation of E would destroy the argument. However, because its technically irreleveant or becuase its already been considered the negation of E really doesnt matter either right?

Therefore, the negation test works for answering Nec. Assump. questions only if the answer is relevant to the question?

[timmydoeslsat]

Got it. Thank you.

I am also curious of one more thing though. The negation of E would destroy the argument. However, because its technically irreleveant or becuase its already been considered the negation of E really doesnt matter either right?

Therefore, the negation test works for answering Nec. Assump. questions only if the answer is relevant to the question?

First, I would say that the negation of E is not destroying the argument. We know that the biological and chemical costs of processing are about the same. So when you state that it is greater, it is not a big deal. Greater by one cent? Two cents? A dollar? The any part is too strong since we are told they are about the same cost.

The true gap in the reasoning is that while we have the processing cost being about the same between B and C, we know that B produces 20% less waste. Also, waste disposal is a huge part of the overall cost. But we cannot validly infer that B is going to be cheaper than C simply because B is producing less waste. What is the cost discrepancy between getting rid of B versus that of C? That is the fundamental gap in the argument.

When dealing with answer choices in necessary assumption question stemss, be wary of:

- Primarily
- Best
- Any
- All
- Most

Not to say that these will never work, but something being necessary to the argument is generally not a lot. It truly depends on the context of the argument.

[demetri.blaisdell]

Great stuff here, you two. Timmydoeslsat is right on in identifying the gap. Less waste doesn't mean it's cheaper to clean up. Is it easier to clean up 10 pounds of radioactive waste or 20 pounds of dirt?

Be very careful on the negation test. "Not any greater" doesn't change to "way greater." The proper negation is something like:

Labor costs associated with tanning leather using biological catalysts are at least a little greater than the labor costs associated with the conventional tanning process.

When you do it properly, it's easy to see why the argument isn't destroyed by the negated version of (E).

I hope this helps. I love to see you two getting in to these problems.

Demetri

[njsim10]

I'm still a little confused about this question. It says 'if waste disposal is left out of the comparison'. That's why I didn't pick option D. Are we not supposed to leave it out of the comparison?

[wgutx08]

No we are not --- there is a "however" in the next sentence, starting to discuss the waste disposal.

say,

This cardigan is so much prettier than that sweater if the color is left out of the comparison. However, I'd rather be killed than wear something in that hideous purple. So I will certainly buy the sweater instead.

isn't this argument very much about color although I said "if the color is left out" at the beginning?

And something like
"The sweater is not in a even more hideous color"
can very well work as a necessary assumption for my argument, right?

hope that helps