PrepTest 123

[lcid:3589] Prep Test 123 LSAT — Logical Reasoning — S2 Logical reasoning

Question prompt

Philosopher:  An action is morally Remaining source text redacted.
Why the credited answer is right

Credited answer: C

The notes below walk through why it fits the stem and how to eliminate the rest.

Argument or Facts

Argument

Valid or Flawed

Flawed

Question Type

Strengthen with Sufficient Premise Questions / Sufficient & Necessary Questions

Stimulus Summary

Reasonable expectation of increasing well-being → Morally right
Reasonable expectation of reducing well-being ← → Morally wrong
Therefore: Reasonable expectation of not changing well-being → Morally right

Answer Anticipation

First, some notes on the stimulus. The second statement is a biconditional, as established by the "if and only if" language. It's also important to note here that the negation of Morally right isn't Morally wrong, and vice versa—there exists the possibility that something is morally neutral.
This question is very interesting. The first premise is a conditional rule that guarantees an action is morally right—which is where the conclusion wants to end up—but the conclusion's sufficient condition and the premise's can't overlap since increasing and leaving well-being the same are logically not equivalent.
The contrapositive of that rule (short version): not Morally right → not Increase well-being. That also doesn't help us in our attempt to make this argument valid since it doesn't overlap with the conclusion in a helpful way. While Doesn't change well-being falls under the umbrella of not Increase well-being (if something doesn't change well-being, then it doesn't increase it), it's on the wrong side of the conditional to chain together. We'll have to look at the second premise to see if there's some connection to the conclusion that we can work with.
Looking at the second, we run into similar issues, but it's important to remember here, we're dealing with a biconditional statement. The contrapositive is similarly biconditional:
not Morally wrong ← → not Reduce well-being
This, too, doesn't seem to build to the conclusion, but don't forget that biconditionals work in both directions, so we could reframe it as:
not Reduce well-being ← → not Morally wrong
Similar to the first conditional, there is some overlap between not Reduce well-being and Not change well-being. Mainly, if something doesn't change well-being, then it doesn't reduce well-being (the reverse isn't true). So:
Not change well-being → not Reduce well-being ← → not Morally wrong
Using the second premise and a relationship that has to be true (the first link in that conditional chain), we can prove that actions that don't change well-being are not morally wrong. Since the conclusion is that these actions are morally right, we can connect those two ideas to validate it:
not Morally wrong → Morally right
That was a long way to go, and a lot of tactical use of knowledge of the LSAT and conditional logic. We'll discuss how to approach the answer choices if you didn't do this work during your anticipation step while looking at them.

Answer choices

  1. A
    Only wrong actions would Remaining source text redacted.
    Why choice A is not credited
    Incorrect. Reasonably expected to reduce well-being → Morally wrong. This answer choice just restates half of our biconditional. Since it doesn't add anything, it can be eliminated. This answer choice would just require you to understand the biconditional and be able to diagram it to eliminate!
  2. B
    No action is both Remaining source text redacted.
    Why choice B is not credited
    Incorrect. In other words, if an action is wrong, then it's not right, and if it's right, then it's not wrong. That doesn't provide any information that would help prove something is right, which is what the conclusion is trying to do. Since it's not helping to build to the conclusion, it can be eliminated even without a strong anticipation.
  3. C
    Any action that is Remaining source text redacted.
    Why choice C matches the stem
    Correct. not Morally wrong → Morally right. Even if you didn't have a solid anticipation, this answer choice overlaps with the conclusion by justifying that there is a condition that guarantees something being morally right. Without an anticipation, this answer choice should be analyzed to see if it can be built to connect Not change well-being to Morally right (the conclusion). And since not changing the aggregate well-being guarantees that well-being isn't decreased (or increased, but that's not relevant here), the biconditional guarantees that it is not morally wrong, and this answer choice bridges the gap in the conclusion.
  4. D
    There are actions that Remaining source text redacted.
    Why choice D is not credited
    Incorrect. This answer choice is more in Necessary Assumption language, bringing up that one of the terms does, in fact, exist in the real world. That's generally not going to be strong enough to justify a strong conclusion, which we have here since it's a conditional.
  5. E
    Only right actions have Remaining source text redacted.
    Why choice E is not credited
    Incorrect. Good consequences → Morally right. This answer choice does overlap with the conclusion in that it has Morally right as a necessary condition, but the sufficient condition isn't directly related to the other half of the conclusion. "Good consequences" is ill-defined and doesn't necessarily overlap with leaving the aggregate well-being unchanged, so this answer choice is out of scope. In general, answer choices that introduce new terms in Strengthen with Sufficient Premise questions are wrong.

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