#24 - The Kiffer Forest Preserve, in the northernmost part

[Daliax]

The pre-phrase helps evaluate answers by seeing if they match the main idea. Answer E fits because it suggests the bear population in the valley stays steady, despite growth in the Preserve. Small differences, like "about the same," don't change the reasoning much.

[Jeff Wren]

Hi Daliax,

Excellent point!

[misheleleee]

E was one of my last contenders but I ultimately did not pick it because I thought that it was a trap answer that would not weaken the argument. Just because the bear population in valley didn't increase in the past 8 years, doesn't mean that it can't increase in the future, like the conclusion says.

Is my reason for eliminating E invalid in this question specifically because the conclusion about the valley's population increasing is based on an erroneous assumption that the valley's population has increased because the preserve's population increased?

[misheleleee]

E was one of my last contenders but I ultimately did not pick it because I thought that it was a trap answer that would not weaken the argument. Just because the bear population in valley didn't increase in the past 8 years, doesn't mean that it can't increase in the future, like the conclusion says.

Is my reason for eliminating E invalid in this question specifically because the conclusion about the valley's population increasing is based on an erroneous assumption that the valley's population has increased because the preserve's population increased?

Hi! Just wanted to follow up on this Thanks!

[Jeff Wren]

Hi misheleleee,

You asked:

"Is my reason for eliminating E invalid in this question specifically because the conclusion about the valley's population increasing is based on an erroneous assumption that the valley's population has increased because the preserve's population increased?"

That's correct.

As I mentioned in an earlier post (Post #18), this argument contains the flaw known as an error of composition (often called the part-to-whole flaw).

Answer E addresses this flaw. By stating that the bear population of the valley stayed about the same over the eight years, it confirms that what happened to part of the valley (the Preserve) did not also happen to the entire valley. Based on this fact, there would be no reason given in the argument to conclude that the bear population of the entire valley would increase simply because the bear population of the Preserve increased.

You wrote:

Just because the bear population in valley didn't increase in the past 8 years, doesn't mean that it can't increase in the future, like the conclusion says.

Based on this statement, it looks like you are probably approaching this Weaken question the wrong way. Sure, it's possible that the bear population of the valley could increase. Anything is possible. However, the conclusion of the argument is that the bear population of the valley will increase (if the road remains closed).

Any answer that casts doubt on that conclusion weakens in the argument. In other words, any answer that provides a reason to think that the bear population of the valley may not increase weakens the argument. Answer E does this. Since the bear population of the valley did not increase in the past eight years despite the increase in the Preserve, there's no reason whatsoever (at least none given in the argument) to conclude that it will increase going forward.