Logical ReasoningDifficulty: Hard

PT123 S2 Q23 Explanation

Philosopher: An action is morally right if

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsSufficient Assumption

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Stimulus

Philosopher: An action is morally right if it would be reasonably expected to increase the aggregate well-being of the people affected by it. 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, actions that well-being of the people affected by them are also right.

What this question is testing

Sufficient Assumption

Your task

Find the assumption that, if added, guarantees the conclusion follows.

Common trap

Answers that only partly bridge the gap, leaving the conclusion unproven.

Winning move

Identify the new term in the conclusion and pick the choice that links it to the evidence.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
23.

The philosopher’s conclusion follows logically if which one of the following

Answer choices

  1. Unrelated to Goal15% picked this

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

    We need to be convinced that if something "isn't wrong" then it's "right". This doesn't have any power to do such a thing. This actually reiterates part of what we get from the bi-conditional rule. if it decreases well being, then wrong.

  2. No Impact8% picked this

    No action is both right and

    We need to know that if an action "isn't wrong" then it's "right". In other words, we want to know that every action is either right or wrong. This answer tells us that no actions are BOTH right and wrong. But it still leaves open the possibility that some actions are neither right nor wrong. There might be three types of actions: right, wrong, neutral The actions our conclusion cares about are actions that don't affect well-being. We know from one of the conditional premises that such actions are "not wrong". But this answer leaves open the possibility that such actions could be Right or just Neutral. So we haven't proven the conclusion. We haven't proven that such actions are Right.

  3. Correct61% picked this

    Any action that is not morally wrong is

    Why this is right

    We were looking for "If it isn't wrong, then it's right", and that's exactly what this is giving us. Since actions that don't affect well-being don't decrease well-being, we know (from the premises) that they are not morally wrong. Now, according to this answer, we know that if they are not morally wrong, then they are morally right. So we've proven that actions that don't affect well-being are morally right.

    Skill tested: Sufficient Assumption · how this choice captures the argument's function is the move to repeat next time.

  4. Too Weak14% picked this

    There are actions that would be reasonably expected to leave unchanged the aggregate well-being of the

    This is necessary for the argument to be valid, but is not sufficient to guarantee that such actions are morally right. This is telling us that "actions that don't affect well-being" do in fact exist. We know from the premises that such actions aren't morally wrong. But we need to be able to prove that they are morally right, and this answer has no power to prove that something is morally right.

  5. Bad Evidence/Trigger Match2% picked this

    Only right actions have good

    This provides a conditional that allows us to prove that an action is "right", which is our whole goal! (Only this and choice (C) have that essential feature) The rule is "if an action has good consequences, then it's right" Okay, did the evidence establish that "actions that don't affect well-being have good consequences"? No, it didn't. In fact, it's almost a self-contradiction. If it doesn't affect well-being, then how could it have good consequences. Since the actions we're dealing with in the conclusion don't trigger this conditional, it's useless to us.

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