PT123.S2.Q23

PrepTest 123 - Section 2 - Question 23

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Philosopher: Support An action is morally right if it would be reasonably expected to increase the aggregate well-being of the people affected by it. Support An action is morally wrong if and only if it would be reasonably expected to reduce the aggregate well-being of the people affected by it. Thus, Conclusion actions that would be reasonably expected to leave unchanged the aggregate well-being of the people affected by them are also right.

Argument Summary

The philosopher gives us two principles that assign moral labels based on an action's expected effect on aggregate well-being, then tries to extend those labels to a third category.

Principle 1: If an action is reasonably expected to increase aggregate well-being → morally right.

Principle 2: An action is morally wrong if and only if (making this a biconditional) it is reasonably expected to reduce aggregate well-being.

That "if and only if" means both of the following:

  • Expected to reduce well-being → morally wrong
  • Morally wrong → expected to reduce well-being

And we can also infer this from the "if and only if" statement:

  • NOT expected to reduce well-being → NOT morally wrong

The conclusion: actions expected to leave well-being unchanged are also morally right.

So there are three possible effects on well-being: increase, decrease, and unchanged. The premises assign moral labels to the first two (right and wrong, respectively). The conclusion tries to slap a label on the third: also right.

The Missing Link

What can we already prove about actions that leave well-being unchanged?

You might first look at Principle 1, since it's the one that leads to "morally right." But Principle 1 triggers when well-being is expected to increase. If well-being is unchanged, it's not increasing. So Principle 1 can't help us here.

What about Principle 2? If well-being is unchanged, it's not decreasing. And the biconditional tells us: not expected to decrease → not morally wrong. So we can already prove, from the premises alone, that actions leaving well-being unchanged are not morally wrong.

But the conclusion says these actions are morally right. And "not morally wrong" isn't the same thing as "morally right" unless there's no middle ground. Think about sorting laundry into a "clean" basket and a "dirty" basket. If a shirt isn't in the dirty basket, is it clean? Only if there's no "worn once, probably fine" pile on your bedroom floor.

Here's the missing piece of the argument:

From Premise 2: unchanged well-being → not expected to reduce → not morally wrong
Missing bridge: not morally wrong → morally right
Conclusion: unchanged well-being → morally right

We're looking for an answer that says there's no moral middle ground. If an action isn't wrong, it's right. The correct answer could also express this as "if an action isn't right, it's wrong."

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23.

The philosopher's conclusion follows logically if which one of the following is assumed?

a

Only wrong actions would be reasonably expected to reduce the aggregate well-being of the people affected by them.

This restates something we already know from Principle 2. The word "only" introduces a necessary condition, so (A) is saying: expected to reduce well-being → wrong action. That's just one direction of the biconditional we were already given. Adding information we already have to the argument can't make it valid. We need a connection between "not morally wrong" and "morally right," and (A) doesn't provide that.

15%
b

No action is both right and wrong.

This says the categories "right" and "wrong" don't overlap. But the problem isn't overlap. The problem is that there might be actions falling into neither category. Knowing that right and wrong are mutually exclusive doesn't eliminate the possibility of that an action is neither right nor wrong.

To see why, consider: "no cats are dogs" doesn't prove your neighbor's pet is a cat. It could be a hamster. Similarly, knowing an action can't be both right and wrong doesn't prove that a "not wrong" action must be right. It could be morally neutral, which is exactly the gap this argument needs to close.

If you diagram (B), it says: right → not wrong (and wrong → not right). But we need: not wrong → right. Those aren't the same relationship. (B) tells us what follows from being right, but we need to establish what follows from not being wrong.

7%
c

Any action that is not morally wrong is morally right.

This is exactly the bridge we identified. It says not morally wrong → morally right. Combined with what the premises already establish (unchanged well-being → not expected to reduce well-being → not morally wrong), we get the full chain: unchanged well-being → not morally wrong → morally right. That's the conclusion, and now it's guaranteed.

63%
d

There are actions that would be reasonably expected to leave unchanged the aggregate well-being of the people affected by them.

This asserts that actions with neutral effects on well-being exist. But the conclusion isn't trying to prove these actions exist. It's trying to prove that if they exist, they're morally right.

13%
e

Only right actions have good consequences.

This introduces "good consequences," a concept that doesn't appear anywhere in the premises. The word "only" makes this: good consequences → right action. But to use it, we'd need to know that unchanged well-being counts as a "good consequence," and nothing in the argument establishes that. Without that connection, (E) just sits there, unable to link up with any part of the existing chain.

2%

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