Logical reasoning PrepTest 153 · Section 2 · Question 9

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Point at Issue

Stimulus Summary:
Ellen (Degeneres? I hope it's Degeneres) argues that protection of the Earth's biosphere should be a high priority, because its so-called "essential services" are worth an estimated $33 trillion annually.

Santiago doesn't like her line of reasoning, because determining the Earth's biosphere should be protected based on its monetary value suggests that it's important mostly because it provides humans with valuable "services."

Strategy Overview:
Look for each speaker's conclusion, and determine if they disagree upon either of those points. If not, check to see if one speaker's conclusion disagrees with a premise or subsidiary conclusion of the other's argument. Remember that the correct answer to a Disagree question is always a statement that Must Be True for one speaker and Must Be False for the other.

Answer Anticipation:
Santiago doesn't seem to disagree that biosphere protection should be a priority, but he does seem to think we shouldn't argue for such protection by reducing the biosphere's importance to its dollar value to humanity. We're probably looking for something about that issue.

Answer Explanation:
Nice of them to put the correct answer first so you don't have to read the word "biosphere" too many more times. Yes, this is correct. Ellen would call this a Must Be True, and for Santiago it's a Must Be False.

Key Takeaway:
Two-perspective questions are getting more and more common on the LSAT, so make sure to practice them. The fastest way through a Disagree is by sticking to the "MBT for one, MBF for the other" mantra. If you apply this scrupulously, you'll get the right answer every time.

Incorrect. Probably a Must Be True for Santiago, but Ellen never stated an opinion on this. Both people need to have an opinion for a Disagree answer to be correct.

Incorrect. Ellen likely considers this to be true, but Santiago never gave an opinion on the effectiveness of this line of reasoning. Rather, he thinks this way of thinking is morally wrong.

Incorrect. Ellen thinks this Must Be False, since she's using such calculations in her argument, but Santiago hasn't taken a stance on it.

Incorrect. Both speakers seem to agree on this. It's just that Santiago has a problem with it, while Ellen thinks that's just fine.