Logical Reasoning

PT141 · S4 · Q10 Vacuum cleaner salesperson: To prove

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Vacuum cleaner salesperson: To prove that this Super XL vacuum cleaner is better than your old vacuum cleaner, I ran your old vacuum once over this dirty carpet.

Conclusion (proving that)

The Super Xl is better than your old vacuum cleaner.

Evidence

I ran your old vacuum once over this dirty carpet. Then I ran the Super XL over the same area. It was able to pick up all the dirt that the old vacuum left behind.

Evaluate

This doesn't seem like a fair way to compare two vacuums.

What if you wanted to see which pink paint will better hide that brown wall: You paint a coat of Paint 1. You can still see some brown spots poking through; the color seems thin in other places.

You paint a coast of Paint 2. Now the brown spots are covered up. The color seems nice and saturated everywhere.

Do you conclude that Paint 2 did the better job of covering up the wall? No, because it wasn't a fair fight. A better head-to-head experiment would be dividing up the original brown wall into two halves, and painting a coat of Paint 1 on one half and a coat of Paint 2 on the other half. That would allow us to judge how well each paint covers up a dark brown wall.

Similarly, to measure the suckitude of these vacuums, we should let the old vacuum do this half of the room, let the Super XL do that half of the room (assuming both halves are equally dirty), and compare which carpet has the most residual dirt.

Goal

Look for an answer complaining about the unfair head-to-head comparison. Judging one vacuum's 2nd lap around a dirty carpet against another vacuum's 1st lap around that carpet isn't an apples to apples comparison we can really evaluate.

10.

The vacuum cleaner salesperson's argument is most vulnerable to the criticism that it

  1. ignores the possibility that dirt

    Doesn't Hurt

    Since this answer begins with fails to consider / ignores the possibility, we can ask ourselves whether the idea it presents would be an Objection. "Hey, author -- the Super XL isn't necessarily better. After all, there was still some dirt in the carpet even after the Super XL was used on it." That does seem to weaken a bit. However, it's a weak idea. Was the author saying something strong, like "The Super XL is supposed to get rid of all the dirt on any area of carpet it goes over?" No, it only said "all the dirt that was picked up (which is not necessarily all the dirt that was on the carpet) was stuff that the old vacuum failed to pick up". If the old vacuum the carpet 60% dirt-free, and after the Super XL went over the carpet, it was 90% dirt free, this answer is saying that 100% of that extra 30% that the Super XL grabbed was missed by the old vacuum. But the fact that 10% of the dirt is still on the carpet doesn't change the author's argument that the Super XL is better than the old vacuum.

    2% picked this

  2. takes for granted that the

    Not Assumed

    Since this answer begins with takes for granted / presumes / fails to establish, we can ask ourselves whether the argument needed to make this Assumption. Was the author assuming / promising that the Super XL will be better than the old vacuum when it's x years old? No, the author's conclusion is very specific and present tense. She's proving that "this Super XL vacuum cleaner is better than your old vacuum cleaner". She might even admit that the old vacuum cleaner this potential customer has was the better unit, in its heyday. She's trying to make her sale by just pointing out that the Super XL is currently outperforming their old vacuum cleaner.

    3% picked this

  3. takes for granted that because

    Not Assumed Too Strong: best

    Since this answer begins with takes for granted / presumes / fails to establish, we can ask ourselves whether the argument needed to make this Assumption. No, it doesn't need to assume that Super XL is the best; it's only trying to prove that it's better than this potential customer's old vacuum.

    2% picked this

  4. ignores the possibility that the

    Doesn't Hurt

    Since this answer begins with fails to consider / ignores the possibility, we can ask ourselves whether the idea it presents would be an Objection. "Hey, author -- the Super XL isn't necessarily better. After all, the old vacuum actually picked up more dirt than the Super XL!" That does seem to weaken a bit. However, the author has a pretty clear response available -- "Of course the old vacuum picked up more dirt; it went first!" If the old vacuum the carpet 60% dirt-free, and after the Super XL went over the carpet, it was 90% dirt free, this answer is saying that the old vacuum picked up 60% of the dirt, whereas the Super XL only picked up 30% of the dirt. The author is thinking, "If we had done the Super XL first, it would have picked up 90% of the dirt. Say you were attempting a crossword puzzle with 40 clues on it. You figure out about 25 of them and then give up. Someone else comes along and figures out another 10 of them. Who's the better crossword player? It's hard to say. The first person figured out more clues, but they got first crack at the puzzle, so they may have gotten all the easier ones that Person 2 would have gotten as well.

    27% picked this

  5. Correct

    ignores the possibility that if

    Why this is right

    Since this answer begins with fails to consider / ignores the possibility, we can ask ourselves whether the idea it presents would be an Objection. "Hey, author -- the Super XL isn't necessarily better. After all, if you had used the Super XL first, you would have had just as must residual dirt as the old vacuum cleaner." This indirectly points to the unfair fight of how the salesperson did the head-to-head test. We're essentially objecting, "What if, in a fair fight, the Super XL just tied the old vacuum?"

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

    67% picked this

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