A certain gene can be stimulated by chemicals in cigarette smoke, causing lung cells to metabolize the chemicals in a way that makes the cells cancerous. Yet smokers in whom this gene is not stimulated have as high a risk of developing lung cancer from smoking as other smokers do.

Summary
A certain gene can be affected by chemicals in cigarette smoke.
When the gene is affected in this way, it causes lung cells to metabolize in a way that makes the cells cancerous.
Smokers in whom this gene is not stimulated have as high a risk of developing lung cancer from smoking as other smokers do.

Very Strongly Supported Conclusions
There’s no obvious conclusion to draw, but I’d observe that the facts seem to present a discrepancy. We’d expect that smokers in whom the gene is stimulated should be at a higher risk of lung cancer. The fact that they aren’t is strange. This suggests there might be something about the smokers in whom this gene is stimulated that might work to reduce the risk of lung cancer.

A
stimulation of the gene by chemicals in cigarette smoke is not the only factor affecting the risk for smokers of developing lung cancer
This is strongly supported, because if it weren’t true, then we’d expect the smokers in whom the gene is stimulated to have a higher risk of lung cancer. The fact that they don’t implies that there are other factors relevant to lung cancer that might work to reduce the smokers’ risk.
B
nonsmokers have as high a risk of developing lung cancer as do smokers in whom the gene has not been stimulated
The stimulus compares the risk of lung cancer in one kind of smoker compared to another kind of smoker. We don’t get a comparison between smokers and nonsmokers.
C
smokers in whom the gene has been stimulated are more likely to develop lung cancer than are other smokers
The stimulus provides evidence against (C). Smokers in whom the gene is stimulated have “as high a risk” of lung cancer from smoking as other smokers do. This suggests the risk of lung cancer, at least from smoking, is equivalent in the two kinds of smokers.
D
the gene is more likely to be stimulated by chemicals in cigarette smoke than by other chemicals
The stimulus doesn’t compare what is more likely to stimulate the gene.
E
smokers are less likely to develop lung cancer if they do not have the gene
If anything, the stimulus provides some evidence against (E). Smokers in whom the gene is stimulated have “as high a risk” of lung cancer from smoking as other smokers do. This suggests the risk of lung cancer, at least from smoking, is equivalent in the two kinds of smokers.

3 comments

Commissioner: Budget forecasters project a revenue shortfall of a billion dollars in the coming fiscal year. Since there is no feasible way to increase the available funds, our only choice is to decrease expenditures. The plan before you outlines feasible cuts that would yield savings of a billion dollars over the coming fiscal year. We will be able to solve the problem we face, therefore, only if we adopt this plan.

Summarize Argument

The commissioner concludes that the only way to solve the problem of the revenue shortfall is by adopting his plan. He supports this with three premises:

(1) Budget forecasters predict a billion-dollar shortfall next year.

(2) We can't increase funds, so we must cut spending.

(3) This plan would cut spending and save a billion dollars.

Identify and Describe Flaw

This is the cookie-cutter flaw of mistaking sufficiency for necessity. The author treats “his plan” as necessary for “solve the problem.” But according to the premises, “his plan” is sufficient, not necessary.

In other words, the commissioner’s argument is flawed because he ignores the possibility that some other plan or solution could also solve the revenue shortfall. His plan might not be the only option.

A
relies on information that is far from certain

We have no reason to doubt the forecasters’ prediction and we can’t assume that it’s uncertain.

B
confuses being an adequate solution with being a required solution

The commissioner confuses an adequate (or sufficient) solution— his plan— with being a required (or necessary) solution. But just because his plan would solve the problem doesn't mean that it’s the only way to solve the problem.

C
inappropriately relies on the opinions of experts

The commissioner points to budget forecasters’ prediction about next year’s revenue shortfall. He relies on experts, but he doesn’t do so inappropriately since the experts’ prediction is within their own field.

D
inappropriately employs language that is vague

The commissioner uses clear and precise language throughout his argument. He doesn't inappropriately rely on vague language.

E
takes for granted that there is no way to increase available funds

The commissioner’s claim that there is no way to increase funds is a premise; we must accept that it’s true. So (E) doesn't describe a flaw in his argument.


4 comments

Ambiguity inspires interpretation. The saying “We are the measure of all things,” for instance, has been interpreted by some people to imply that humans are centrally important in the universe, while others have interpreted it to mean simply that, since all knowledge is human knowledge, humans must rely on themselves to find the truth.

Summarize Argument
The author claims that “ambiguity inspires interpretation.” The argument proceeds with an example to prove this claim: a particular phrase is ambiguous, and has therefore been interpreted in different ways by different people.

Identify Argument Part
The claim that “ambiguity inspires interpretation” is the main conclusion of the argument. It is supported by the example of an ambiguous phrase that has prompted interpretation.

A
It is used to support the argument’s conclusion.
The claim that “ambiguity inspires interpretation” does not support anything else in the argument. Instead, it is supported by an example.
B
It is an illustration of the claim that we are the measure of all things.
The author never actually claims that we are the measure of all things. That’s just an example of an ambiguous phrase, not something that’s argued to be true. Also, nothing in the argument illustrates that we are the measure of all things.
C
It is compatible with either accepting or rejecting the argument’s conclusion.
Since the claim that “ambiguity inspires interpretation” is the argument’s conclusion, it cannot be compatible with rejecting the argument’s conclusion. That would be self-contradictory.
D
It is a view that other statements in the argument are intended to support.
This describes the main conclusion, which is precisely what the claim that “ambiguity inspires interpretation” is. The only other statement in the argument is an example which illustrates this principle, thereby supporting it.
E
It sets out a difficulty the argument is intended to solve.
The argument doesn’t attempt to solve any kind of difficulty. The author’s goal is instead to demonstrate a particular claim to be true through the use of an example.

3 comments