Logical Reasoning

PT149 · S1 · Q6 The only vehicles that have high resale values

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

  • Save & drill this skill — build targeted practice sets from questions like this one

  • Video walkthroughs — watch every question solved step by step

  • 81 official LSATs — as questions, timed sections & full-length tests

Start practicing free

The only vehicles that have high resale values are those that are well maintained.

Evidence

The only vehicles that have High Well high resale value are those Resale → Maintained that are well maintained.

Conclusion

Any vehicle that is well Well High maintained has a high Maintained → Resale resale value.

Evaluate

This argument just presents a conditional premise (A → B) and then illegally concludes that the reverse would be true (B → A).

(country accent) We call that the famous Necessary vs. Sufficient flaw around these here parts.

"the only" is a sufficient indicator that means .

It's more common cousins, "only if" and "only" are necessary indicators that mean .

"any" is a sufficient (LEFT side) indicator, just like all other universals (e.g. all, each, every, none)

Goal

Let's look for an answer that presents a conditional premise and then offers a conclusion that is just the illegal reversal of that conditional rule.

6.

The flawed nature of the argument can most effectively be demonstrated by noting that, by parallel reasoning, we could argue that

  1. since none of the plants

    Bad Conclusion Match

    We can tell this is more than a simple reversal, since the evidence talks about "whether it's been pruned before" and the conclusion talks about "whether it needs pruning". There can't be any new ideas in the conclusion, just the same two ideas in reverse logical order. The correct conclusion here, given the initial premise, would be, Thus, if a plant has never been pruned, it must be in this garden.

    3% picked this

  2. since the best mediators have

    Trap

    Weak Evidence/Conclusion Match Opposite vs. Reversal This premise and conclusion are not conditional claims, so we can stop reading upon seeing that. If the conclusion were reversing the premise, it would sound like, "Thus, mediators with the longest track records are the best mediators". Instead of reversing, this conclusion tried to Flip the Illegal Light switch, by just saying the opposite of both ideas in the evidence.

    1% picked this

  3. since only those who desire

    Bad Conclusion Match

    Since the conclusion isn't a conditional idea (it's just saying that "X is the most important factor involved in Y"), we can immediately bail. If the conclusion were reversing the logic of the premise's conditional, we'd get something like, Thus, any person who desires to become an astronaut will actually become an astronaut.

    5% picked this

  4. Correct

    since all city dwellers prefer

    Why this is right

    Both premise and conclusion are conditional ideas. They both contain the same two concepts and simply reverse the logical order of them. Premise city dweller → prefer waterfall to traffic jam Conclusion prefer waterfall to traffic jam → city dweller

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

    86% picked this

  5. since one’s need for medical

    Bad Premise Match

    This premise is not conditional. It's a Volume Dial type idea "the more improved health, the less need for medical care". Once we see the premise isn't conditional, we know we can't replicate the Necessary vs. Sufficient error (aka the Conditional Logic flaw). It's also not really a reversal. The conclusion is just an overly hyperbolic application of the volume dial idea. If someone is in excellent health, we would think that they need medical care less than someone in good to poor health. But we wouldn't be able to go to the extreme language of no need for medical care.

    5% picked this

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

Save and practice this skill
LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free