Logical reasoning PrepTest 109 · Section 3 · Question 12

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Methods of Reasoning

Stimulus Summary:
Opposing point: Physicians don't prescribe herbs because they're not effective.

Author: It's really expensive to get a drug approved to be sold, which is a requirement for selling it. Herbs can't be patented, and only someone with a patent can make money off of medicines. So doctors can't recommend herbs as medicines.

Answer Anticipation:
When a Methods of Reasoning question shows up in an argument that has an opposing point/rebuttal structure, it's important to define how the main point relates to the opposing point, and what the author presents to rebut the facts or logic from the opposing point.

Here, the opposing point sets out an explanation for why doctors don't prescribe herbs as medicine—they're not effective. How does the main point relate to that? It provides an alternative explanation—they don't prescribe herbs because they can't since they're not approved for medicinal use. The premises bring up considerations that aren't mentioned by the opposing point in order to support this alternative explanation.

This method of reasoning—providing an alternative explanation—is a common method of rebuttal, so let's find an answer describing it.

Answer Explanation:
This answer matches our anticipation and the common method of rebuttal present exactly. Some people claim that herbs aren't prescribed because they don't work; the author supplies the alternative explanation that economics don't allow them to be approved, and thus they can't be prescribed, regardless of their effectiveness.

Key Takeaway:
First, when a Methods of Reasoning question deals with a rebuttal, figure out how the main point and opposing point are related, and what the author brings up to disagree with that opposing point. Second, one common method of reasoning is to argue for an alternative explanation, so be sure to be aware of what that type of argument sounds like—and not just for this question type!

Incorrect. There's no data presented about the effectiveness of herbs in treating illnesses, and the data presented by the author is about the cost of getting regulatory approval for a drug, so this answer is incorrect.

Incorrect. The author here presents new information to support an alternative hypothesis; she doesn't present an inconsistency. A good sign that there is no inconsistency is that there is only a conclusion raised as the opposing point—it's hard to have a single conclusion be inconsistent with itself!

Incorrect. While the argument does deal with alternative explanations no one lists all possible explanations before ruling out all but one. The opposing point just puts forward an explanation without supporting it and the author concludes a separate explanation after supporting it with data. There are presumably other potential explanations for why doctors don't prescribe herbs that are unmentioned in the stimulus.

Incorrect. There's no theory that makes predictions brought up, so this answer is out of scope.