PrepTest 118, Section 1, Question 23
For each action we perform, we can know(39 more words not shown)
The conclusion follows logically if(7 more words not shown)
- AOn some occasions(15 more words not shown)
- BOn some occasions(8 more words not shown)
- CKnowing that an(13 more words not shown)
- DOnly the immediate(13 more words not shown)
- EAn action may(14 more words not shown)
Reading the argument
Do we really have to know every consequence to know which action is best?
Let's accept that we can know only some consequences of an action. Drinking a glass of water may make me less thirsty, while some later effect remains unknown. Knowing the immediate result doesn't mean knowing everything that will happen.
But the argument takes another step. Suppose being morally right means having the best consequences. The author says we could then never know which action is morally right, because we never know all its consequences. Why couldn't knowing the main consequences be enough? What if the unknown effects wouldn't change which action comes out best? Knowing 90 percent isn't knowing everything, but the author hasn't yet shown that anything short of everything must be inadequate.
What we’re looking for
We're asked to supply an assumption that makes the conclusion follow. Close that gap: knowing an action has the best consequences requires knowing all its consequences. Since the passage says we can never meet that requirement, we could never know which action has the best consequences. Under the proposed definition of moral rightness, that also prevents us from knowing which action is morally right.
Working the answers
- A
Knowing that an action is wrong on some occasions doesn't establish what knowledge is required to identify the action with the best consequences. A leaves our central question unanswered: must we know all the consequences?
- B
This says we sometimes can know which action is morally right. That doesn't explain why we could never have such knowledge under the definition the argument considers. We need a link between incomplete knowledge of consequences and the claimed inability to judge, not a bare claim that knowledge is sometimes possible.
- CCorrect
Now complete knowledge is a requirement for knowing that an action has the best consequences. We can know only some consequences, so we fail that requirement for every action. If moral rightness means having the best consequences, we therefore cannot know that an action is morally right. Each step in the argument is now connected.
- D
Limiting the relevant consequences to immediate ones doesn't establish that we must know every consequence. It could instead make the task easier by allowing us to disregard later effects. D gives us no reason that knowing only some consequences must prevent the judgment.
- E
Whether moral rightness varies from person to person is a separate issue. Even if the same action is right for one person and wrong for another, we still need to know why incomplete knowledge of consequences prevents us from determining what is right.
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