One of the effects of lead poisoning

Answer choices

1. A

   Correct70% picked this

   In Van Gogh’s later paintings he painted some things as he

   Why this is right

   This is providing an idea that is necessary for the author's explanation to be plausible. In her mind, Van Gogh has lead poisoning in his later years, and so he sees bright haloes around light sources and thus paints bright haloes around light sources in an attempt to make his painting match what he sees. So she is assuming that at least sometimes he painted things as he saw them. If we negated this answer, that would mean "in his later paintings, Van Gogh never painted things as he saw them". Would that negation weaken the argument? Definitely! So this should be correct. If he never painted things as saw them, and he painted bright haloes around the stars and the sun, then that means that does not see bright haloes around the stars and the sun, which suggests that he did not have lead poisoning. If it's easier, you can think about the negation (he never painted things as he saw them) as weakening by providing an alternate explanation: there weren't bright haloes because that's what his lead-poisoned vision made stuff look like -- he wasn't even painting what he saw -- there were haloes purely because of his artistic purposes.

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

   70%
2. B

   Not Necessary9% picked this

   Van Gogh continued to use paints containing lead after having painted

   While it could strengthen the author's argument if we knew that Van Gogh had ongoing lead exposure, it's not necessary. He definitely had exposure to lead. The author needs to assume that he had enough exposure to trigger lead poisoning, but it's highly possible that this sufficient exposure to lead occurred purely through his work on "Sunflowers". The author doesn't need to assume that he had ongoing lead exposure.

   9%
3. C

   Out of Scope: other symptoms4% picked this

   Van Gogh did not have symptoms of lead poisoning aside from seeing bright haloes

   Whether Van Gogh had other symptoms or only had halo-vision, it wouldn't make any difference to this argument. This argument is definitely assuming that Van Gogh had at least one symptom from lead poisoning (seeing bright haloes around light sources), but it doesn't need him to have only one symptom.

   4%
4. D

   Too Strong: no other11% picked this

   The paints Van Gogh used in the “Sunflowers” paintings had no toxic ingredients

   It doesn't make any difference to this argument whether the paints used in "Sunflowers" had other toxic ingredients. It would only matter if those other toxic ingredients also could explain bright haloes around light sources. And we have no common sense reason to think that toxic ingredients generally cause bright haloes, so if we negate this and get, "Yo author -- there were other toxic ingredients in the paints he used", it would be a very weak objection because we have no reason to think that those other ingredients would be an Alternate Explanation for the bright haloes.

   11%
5. E

   Too Strong6% picked this

   The effects of Naples yellow could not have been achieved using

   Too Strong: could not have been achieved This answer is saying that Naples yellow was the only pigment that could achieve a certain effect. We don't have any restrictive language like that in the paragraph. We just know that Van Gogh used Naples yellow; we don't know he had to use it to achieve a certain effect.

   6%