PREP 19 Gortland Assumption

[amysky_0205]

Gortland has long been narrowly self-sufficient in both grain and meat. However, as per capita income in Gortland has risen toward the world average, per capita consumption of meat has also risen toward the world average, and it takes several pounds of grain to produce one pound of meat. Therefore, since per capita income continues to rise, whereas domestic grain production will not increase, Gortland will soon have to import either grain or meat or both.,

Which of the following is an assumption on which the argument depends?

(A)The total acreage devoted to grain production in Gortland will soon decrease.
(B)Importing either grain or meat will not result in a significantly higher percentage of Gortlands' incomes being spent on food that is currently the case.
(C)The per capita consumption of meat in Gortland is increasing at roughly the same rate across all income levels.
(D)The per capita income of meat producers in Gortland is rising faster than the per capita income of grain producers.
(E) People in Gortland who increase their consumption of meat will not radically decrease their consumption of grain.

I crossed out A.B.D and chose C

OA is E.

thank u.

[tim]

Before we help with this question, we need you to show some effort of your own. What did you try on this question? Where did you get stuck?

[rte.sushil]

Even i selected C when i solved this question, here is my reasoning:

Since in the question it is mentioned that as per capita income is rising + per capita consumption of meat is rising..
several pounds of grains = one pound of meat and if grain production doesn't increase then they have to import

now if i think? in what cases grain production is rising? one assumption comes in mind is :- that as income is rising , eople are eating more meat ,,,,if i say meat,,,grain is included with it because it may quite possible that if import of grain happens , then they can make meat at home. if meat is imported then it is directly avaialable


In E, if i think , that those who are increasing meat wil not decrease grain,,,i felt as increase of meat is already increasing grain automatically. if i say meat consumption is increased, then i have already included grain consumption.


Please help me in clarifying my doubt in understanding that what went wrong in my thinking?


Thanks

[tim]

this question is asking what assumption is necessary. a necessary assumption is one where the argument will fail without the assumption. so let's use the negation technique, taking the opposite of the answer choices and seeing if they cause a problem for the argument.

look at C: what if there is a single tiny income level where per capita meat consumption is not increasing. does this mean Gortland will no longer have to worry about importing meat or grain? of course not, so C is not necessary.

with E, what if people who eat more meat DO radically decrease their grain consumption? Gortland might actually get by without importing meat or grain, which messes with the conclusion. So in this sense E is necessary to the conclusion in a way that C is not.

[Levent-g]

Hi Tim,

I also understood that in the argument there is an causality between grain and meat production, like for instance that you need grain to feed the animals to produce meat. Nowhere in the argument a grain consumption by the Gortland population is mentioned, but instead that it takes several pounds of grain to produce one pound of meat.

Therefore it seemed to me that choice E is kind of out of scope, since the problem isn't the grain consumption, but rather the increased meat production and the necessary increasing grain to be able to produce.

Regarding choice C I don't understand your point. The argument mentiones that the meat consumption is increasing due to the rising per capita income. Choice C negates that and sounds like the statement in the argument isn't true. Because if the meat consumption in Gortland is same across all income levels, then a rising income would not lead to increased meat consumption.

Could you please explain a bit further?

Thanks

Levent

[jlucero]

Hi Tim,

I also understood that in the argument there is an causality between grain and meat production, like for instance that you need grain to feed the animals to produce meat. Nowhere in the argument a grain consumption by the Gortland population is mentioned, but instead that it takes several pounds of grain to produce one pound of meat.

Therefore it seemed to me that choice E is kind of out of scope, since the problem isn't the grain consumption, but rather the increased meat production and the necessary increasing grain to be able to produce.

Regarding choice C I don't understand your point. The argument mentiones that the meat consumption is increasing due to the rising per capita income. Choice C negates that and sounds like the statement in the argument isn't true. Because if the meat consumption in Gortland is same across all income levels, then a rising income would not lead to increased meat consumption.

Could you please explain a bit further?

Thanks

Levent

Regarding E, in order to be self-sufficient on grain, you need to produce as much as you consume. Since the conclusion is that this self-sufficiency is going to go away based on a steady production of grain and a need for more grain for the purpose of producing meat, we are assuming that all other uses of grain, including grain used for human consumption, stays the same.

Let's plug in numbers to show this. Let's say most people eat 1 unit of meat and 3 units of grains each day. As per capita income rises, it is possible that people would double their consumption of meat while eliminating all grains. The extra 3 units of grains could offset the extra grain needed to produce meat.

As for C, Tim's point is one that's essential for this type of question: assumptions are things that MUST be true. If E isn't true (and all that extra grain people no longer eat can offset the extra grain needed to produce more meat), the conclusion comes crumbling down. C can be true or false and the conclusion could still hold true. Maybe poorer people's consumption of meat is rising faster than richer people's. Maybe they are rising at the same rate. Regardless, Gortland might still have to import extra grains to meet its demand.

[manhhiep2509]

Hello.

Please take a look my problem and see what is wrong with my reasoning.

I understand that we need an assumption that indicates the grain consumption, that is not used to produce meat, does not decrease more than that, used to produce meat, increases.

Since the correct choice is an assumption, it must be necessary. However, I cannot explain why we need to know about the consumption of people who increase their meat consumption.
What makes those people so special that we need to know about their grain consumption?
How about people who do not increase their meat consumption? If their grain consumption decreases substantially then the choice E may not be necessary to make the conclusion true.

Even I negate the choice, it does not break the conclusion at all because the choice overlook the grain consumption of people who do not increase meat consumption.

Thank you.

[RonPurewal]

Even I negate the choice, it does not break the conclusion at all because the choice overlook the grain consumption of people who do not increase meat consumption.

Thank you.

This reasoning isn't valid unless you consider "People who don't increase meat consumption will also lower their grain consumption significantly" as a reasonable possibility.

... but that's tantamount to saying that those people will, in essence, begin to starve themselves. That's farfetched to start with; in a country whose economy is rapidly growing, it's absurd. So, the argument is indeed destroyed by that negation.

[manhhiep2509]

Even I negate the choice, it does not break the conclusion at all because the choice overlook the grain consumption of people who do not increase meat consumption.

Thank you.

This reasoning isn't valid unless you consider "People who don't increase meat consumption will also lower their grain consumption significantly" as a reasonable possibility.

... but that's tantamount to saying that those people will, in essence, begin to starve themselves. That's farfetched to start with; in a country whose economy is rapidly growing, it's absurd. So, the argument is indeed destroyed by that negation.

Thanks Ron.

You pointed out an aspect I did not realize, i.e. if people do not increase their meat consumption, they will unlikely decrease their grain consumption because grain and meat are basic food to all people.
However, even if your explanation is sound, you still assumed that there is nothing leading to the decrease in grain consumption of those people who do not increase their meat consumption.

I always expect that assumption is must something that we cannot question the connection between assumptions and conclusion. I mean once an assumption is explicated, we cannot find any flaw to question whether it supports the conclusion.

However, in the question, I must make another assumption to make the assumption valid.

So, can I conclude that not all correct assumptions are valid and sometimes we still need to make other assumptions to support the former?

Thank you.

[RonPurewal]

You pointed out an aspect I did not realize, i.e. if people do not increase their meat consumption, they will unlikely decrease their grain consumption because grain and meat are basic food to all people.
However, even if your explanation is sound, you still assumed that there is nothing leading to the decrease in grain consumption of those people who do not increase their meat consumption.

Your point seems to be this: We have to assume that people won't starve themselves.
If that's what you're saying, then, yes, I suppose we have to "assume" that. But we also have to "assume" that the sun will come up tomorrow morning, and so on. In other words, if something is an obvious and universal fact, it doesn't need to be spelled out.

If you don't like that, then you could always call these things "axioms" or "postulates" rather than assumptions.

[AkashicT191]

I know the OA is E, but I thought about it over and over again and still think E is far from airtight.

Say "people in Gortland who increase their consumption of meat will not radically decrease their consumption of grain".

Alright, but how about a plague started and wipes out 95% of the Gortland population? Gortland surely will need no import of neither meat nor grain for a long time. The OA, which is E, at least when I read it, guarantees only the increase of per capital meat and grain consumption , but it doesn't guarantee the number of people from a radical fall, which seems a big opening to me.

[RonPurewal]

Alright, but how about a plague started and wipes out 95% of the Gortland population?

^^ No.

You will never have to consider outlandish/absurd/extreme/crazy scenarios.

If you're even thinking about something like this... that's the end of that train of thought. Done. Don't waste your time.

[RonPurewal]

Gortland surely will need no import of neither meat nor grain for a long time. The OA, which is E, at least when I read it, guarantees only the increase of per capital meat and grain consumption , but it doesn't guarantee the number of people from a radical fall, which seems a big opening to me.

An "assumption" is something that's necessary in an argument. It does NOT "guarantee" anything. So, this whole line of thought is irrelevant.

(Analogy: Vitamin C is necessary for human life. If you don't get it, you'll die.
What you're doing here is like saying, "Vitamin C won't keep you alive all by itself." Sure, but that has nothing to do with the question of whether it's necessary.)

[AkashicT191]

An "assumption" is something that's necessary in an argument. It does NOT "guarantee" anything. So, this whole line of thought is irrelevant.

(Analogy: Vitamin C is necessary for human life. If you don't get it, you'll die.
What you're doing here is like saying, "Vitamin C won't keep you alive all by itself." Sure, but that has nothing to do with the question of whether it's necessary.)

I got it! My understanding of the word 'necessary' was not right! Thank you Ron! Thank you for the correction~!

[tim]

Glad to hear it!