Mo2men wrote:
Dear Mike,
While I was reviewing this question in
Magoosh, there was something interesting about choice B. It is stated that B is weakener. I heard Chris in his video says the same. However, I do not understand how B can weaken the argument. I hope you can clarify this point.
Thanks for your help.
Dear
Mo2men,
I'm happy to respond.
I think to be super-technical, I would say that
(B) could be a weakener. It allows for the possibility of a weakener.
Think about it. At the last government inspection, the radiation levels were at N sieverts, for some value of N. We know that N is above the acceptable safety level S, N > S, because that was the finding in the last inspection. Let's say that the level now is T. How does T compare to N & S? Mathematically, there are four basic possibilities.
Case 1: T > N
Case 2: T = N
Case 3: S < T < N
Case 4: T
< S
Now, choice (B) explicitly eliminates Case 1--it takes Case 1 off the table, so only Cases 2-4 could be true.
If Case 2 or Case 3 is true, then the level now is still above the safety levels, and the conclusion of the argument is untrue. In these cases, (B) would be a clear weakener.
If Case 4 is true, then (B) would still be consistent with the argument's conclusion. Here, (B) would not be a weakener.
If Case 1 is not true, we have no idea which of the other three cases is true. (B) is a weakener in some cases but not in others.
Now, a few things to keep in mind. We are looking for an assumption, and an assumption has an effect of always strengthening the argument. Something that is sometimes a weakener is never a strengthener, never an assumption. Finding out that that (B) allows for some cases that make it a weakener some of the time is enough to disqualify it as a possible assumption. In that sense, it's a weakener---it's a weakener at least some of the time, and that means it absolutely can't be an assumption. That's what is important in answering this question. A weakener some of the time would not be the correct answer if the question were asking for a weakener.
What we get to call a "weakener" to some extent depends on context. If we are answering a weakener question, the bar is high: something always has to be a weakener to qualify for the correct answer to a weakener question. If we are answering an assumption or strengthener question, then the fact that something is sometimes a weakener is enough to disqualify it. As in many things, the bar for disqualification is lower than the the bar for complete acceptance.
Finally, I will say: imagine this scenario--A reporter says, "
The Fieldpark nuclear power plant was cited three years ago by a governmentally led safety commission for exceeding safe levels of radiation. What can you say about the plant's current safety levels?" In response, a Fieldpark PR person say, "
The number of sieverts the plant releases has not increased since the last governmental inspection."
That response is a classic PR-person donkey-feathers answer (PS: that expression was an attempt to avoid the use of profanity of GMAT Club!) All your red flag sensors should go off when you hear that response. It simply sounds like a response that is hiding something. Now, do we know, in a cold logical way, that it is hiding something? Technically, no, but it still should activate all your suspicions. That's the kind of statement that (B) is. In addition to the logical analysis, you also should have a gut-level discomfort about what scam it is trying to pull.
In the real world, once you have your MBA, in the business world, you will encounter all kinds of manipulative people who excel at telling you things that, from a purely logical point of view, could be fine, and if you don't have finely honed intuitions about when someone is trying to defraud you, you could suffer.
Does all this make sense?
Mike
I would like to thank you for taking time to write this response. I'm happy that my pre-thinking matches a lot of your response, especially case 2.