Journalist: Scientists took blood samples

Answer choices

1. A

   Too Strong Assumption: all1% picked this

   It presumes that all human traits are

   We cannot say the author needed to assume that 100% of human traits are genetically determined. We only talked about one trait, liking or disliking vegetables. And even for vegetable-hating, the author is only saying "in at least some cases" it's genetically determined.

   1%
2. B

   Not an Objection5% picked this

   It overlooks the possibility that the volunteers in one or both of the two groups may not have been representative of the human population

   The author doesn't need either of the groups to be representative because the conclusion is not speaking for any more-general group. If I see a 4th grader dunk a basketball, I'm allowed to conclude, "Thus, in at least some cases, a 4th grader can dunk a basketball". That doesn't mean I'm assuming he/she is representative of 4th graders. I can assume he/she is a total freak. They still prove that at least sometimes this can happen. Similarly, it doesn't matter whether these veggie-haters are average or oddballs. Either way, if gene X is causing their veggie-hating, then the author's conclusion is factually true.

   5%
3. C

   No Causality in Evidence12% picked this

   It overlooks the possibility that even when one phenomenon always produces another phenomenon, the latter phenomenon may often be present

   If an answer is structured overlooks the possibility that even when X is true, Y may still be true then it will be correct if and only if it matches like this: overlooks the possibility that even when [Premise is true], [Opposite of Conclusion] may still be true. This answer is saying, "even when one phenom always produces another phenom". We stop there and ask ourselves, "Was there a premise that said that one thing always produces another thing?" Nope. There was a premise that said "one thing always accompanies another thing" (gene X always accompanied the people in the veggie hating group) But produces is causal, and we don't have any causal language until the conclusion. This answer choice is trying to weaken this type of argument: Tickling a baby always makes them giggle. Since I just heard Terry's baby giggling, the baby must have just been tickled.

   12%
4. D

   Even if + Conclusion7% picked this

   It overlooks the possibility that even if a dislike of vegetables is genetically determined, it may be strongly influenced by genes

   It is always wrong to say "If Conclusion ... " or "Even if Conclusion". The former can't be used to strengthen and the latter can't be used to weaken. When we say "even if the conclusion is true, I have this other complaint", the other complaint is meaningless. You just awarded the case to your opponent. You granted them the truth of their conclusion. That's game over.

   7%
5. E

   Correct75% picked this

   It takes for granted that the volunteers in the group that enjoyed eating vegetables did not also all have

   Why this is right

   Did the author need to assume that the veggie-loving group does not also all have gene X? For sure! If the veggie loving group and the veggie hating group all have Gene X, then who would possibly think that Gene X was causing people to hate veggies? In order for something to be a Causal Difference-Maker, it has to be a difference! If we say "Sharon is a better figure skater than Leslie because Sharon has had lessons", then we're assuming that Leslie has not also had lessons. This type of argument pattern is known as Assumes a Difference. It's sometimes such an obvious / implied idea that it's hard for us to notice that it was missing. If I say, "Kevin's waffling between an iPhone and a Samsung. He should go with the iPhone since they're having a sale right now." we hear it implied that only iPhone is having a sale right now. They are special in this way; that's why I only mentioned them. But logically that doesn't count. Just because it's the only thing you've mentioned doesn't establish it's the only thing with that trait. Just because the argument only mentioned that the veggie hating group had gene X is common doesn't mean that the veggie hating group was special for all having gene X in common.

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

   75%