#2 - Brian: I used to eat cheeseburgers from fast-food

[Administrator]

Complete Question Explanation

Flaw in the Reasoning, CE. The correct answer choice is (D).

In his statement, Brian describes a dietary change he made: stopping eating cheeseburgers (meat and cheese) daily and switching to a diet of lean meats, fruits, and vegetables. The result was an observable change in how he felt and in his cholesterol and blood pressure. On the basis of these results, Brian concludes that eating bread and meat in the same meal is unhealthy.


Answer choice (A):

Answer choice (B):

Answer choice (C):

Answer choice (D): This is the correct answer choice. The last sentence is the conclusion, and the idea here is that he stopped eating bread and meat in the same meal, but then also switched his entire diet. So he did something in addition to just cutting out bread and meat; thus we don't know how much of a factor, if any, the cutting out the bread and meat was as opposed to switching diets. This is why D is the correct answer.

Put another way, one part of Brian's change is no longer eating bread and meat in the same meal. Another part of his change was switching to a diet of lean meats, fruits, and vegetables. Essentially, he is saying that his lower cholesterol and blood pressure is because he stopped eating bread and meat in the same meal. In actuality, it could be that the switching to a diet of lean meats, fruits, and vegetables (the "other" part of this change) could have caused the improved cholesterol and blood pressure.

Answer choice (E): This answer choice is factually incorrect. Brian did make the change, and he saw actual results. So, his conclusion rests on his results, not purely what supposedly happened with other people.

[hope]

I chose answer choice E. I think I need help in properly identifying the conclusion which I thought was the last sentence. Is this correct? If so, I don't see how D applies to this conclusion. What "part of a change" is D referring to? And what other parts need to be ruled out? Thanks.

[atierney]

Hi Hope,

Hopefully this will be of some assistance. So, the last sentence is the conclusion as you suggested, and the idea here is that he stopped eating bread and meat in the same, but then also switched his entire diet. So he did something in addition to just cutting out bread and meat; thus we don't know how much of a factor, if any, the cutting out the bread and meat was as opposed to switching diets. This is why D is the correct answer. And, in terms of answer choice E, the answer choice is factually incorrect. Brian did make the change. And his conclusion rests on his results, not purely what he read.

Let me know if you have further questions on this.

[hope]

I'm still not completely clear on the language of D. Is it that the "one part of a change" was cutting out bread and meat which was responsible for the effect of being unhealthy? If so, what is the "other parts of that change which were responsible?" In other words, what specifically did the stimulus fail to rule out? Thanks.

[evelineliu]

Hi Hope,

One part of Brian's change is no longer eating bread and meat in the same meal. Another part of his change was switching to a diet of lean meats, fruits, and vegetables. Essentially, he is saying that his lower cholesterol and blood pressure is because he stopped eating bread and meat in the same meal. In actuality, it could be that the switching to a diet of lean meats, fruits, and vegetables (the "other" part of this change) could have caused the improved cholesterol and blood pressure.

Hope that helps,
Eveline

[hope]

Hi Hope,

One part of Brian's change is no longer eating bread and meat in the same meal. Another part of his change was switching to a diet of lean meats, fruits, and vegetables. Essentially, he is saying that his lower cholesterol and blood pressure is because he stopped eating bread and meat in the same meal. In actuality, it could be that the switching to a diet of lean meats, fruits, and vegetables (the "other" part of this change) could have caused the improved cholesterol and blood pressure.

Hope that helps,
Eveline

It does help Eveline. Thank you so much for the clarity. This one was actually really simple. I just didn't understand the language of the answer.

[jessicawhitley]

D's language still eludes me in many ways. Could it be that cutting out bread and meat was the "one part of a change" that had the detrimental consequences on health?slope game If so, what "other parts which were responsible for that change" are you referring to? Stated differently, what was it specifically that the stimulus failed to rule out? Warm regards.

[Jeff Wren]

Hi Jessica,

Before getting into the specific wording of Answer D, it can be helpful to first be clear on the flaw in the argument itself. (Having a good prephrase before looking at the answers will help make more sense of Answer D.)

In the argument, Brian makes two major changes to his diet. One change is that he stops eating cheeseburgers. (In other words, he stops eating meat and bread at the same time.) The second major change is that he switches to a diet of lean meats, fruits, and vegetables. He then has improved health (such as lower cholesterol and blood pressure). Brian assumes that his improved health is due to no longer eating cheeseburgers (i.e. eating meat and bread at the same time), which is why he concludes that "eating bread and meat at the same time is unhealthy."

The flaw here is that the far more likely cause of his improved health is the switch to eating lean meats, fruits, and vegetables (i.e. a healthy diet) and whether or not he eats meat and bread at the same time has nothing to do with his improved health.

In other words, Brian is making a causal flaw here, specifically he is overlooking a very likely alternate cause (lean meats, fruits, and vegetables) for his effect (improved health).

Answer D describes this flaw. "Concludes one part of a change" (this refers to him no longer eating cheeseburgers/meat and cheese at the same time) "is responsible for an effect" (his improved health) "without considering the possibility that other parts of the change" (now eating lean meats, fruits, and vegetables) "were responsible." This is just a wordy way of describing that Brian ignores the fairly obvious alternate cause for his improved health, his overall switch to a much healthier diet.