#22 - Critic: Almost all of the paintings from our cityʼs

[lawadvocate!]

Hello!

I don't understand this Necessary Assumption question. I selected B. I saw that the correct answer is C. Is this the correct breakdown?

Conclusion: Blue Irises cannot be considered part of the city's art movement.
Evidence: Blue Irises displays bold brushwork. But, it doesn't exhibit a sharp contrast of light & shadow. The stimulus says almost all of the paintings from our city's art movement share two characteristics: bold brushwork & a sharp contrast of light & shadow. The only paintings' from the city's art movement that don't share these characteristics are abstract paintings-which do not depict light or shadow.

So all of the paintings from the city's art movement falls into two camps. One-they share two characteristics (bold brushwork & a sharp contrast of light). OR Two-they're abstract paintings & do not depict light or shadow.

Well, we're told Blue Irises do display bold brushwork, but does not have a sharp contrast of light & shadow so it doesn't fall into the first camp. Looking at the second camp, if it were abstract then it would follow that it is in the city's art movement because it does not depict light & shadow. BUT, we're told it is not considered part of the city's art movement-so it must NOT be abstract.

If you negate Answer C you get Blue Irises is an abstract painting which would demolish the argument because now, it has to be part of the art movement.

Is this correct? Thank you!

[Adam Tyson]

Pretty good, lawadvocate!, but there's one small item I might nitpick about, and that is where you said "if it were abstract then it would follow that it is in the city's art movement." This is a Mistaken Reversal of what we can gather from the stimulus. Being abstract does not guarantee being part of the city's art movement - there could be lots of abstract paintings that are from somewhere else. Rather, being abstract is part of a necessary condition: IF a work is part of the city's movement, THEN it either has bold brushwork and sharp contract of light and shadow, OR it is abstract.

The conclusion is based on the contrapositve - IF an artwork does not have bold brushwork and sharp contract of light and shadow, AND it is not abstract, THEN it is not part of the city's art movement. The author concluded that the sufficient condition did not occur based on only one of those necessary conditions failing to occur. He must have assumed the other necessary condition also failed to occur, for if it had occurred then Blue Irises could be part of the city's art movement. Not that it must be, but that we could not prove that it wasn't.

In short, your analysis was excellent, but for one minor detail that didn't trip you up in this case. I just want to make sure it NEVER has the chance to trip you up! Good job!

[Juanq42]

Pretty good, lawadvocate!, but there's one small item I might nitpick about, and that is where you said "if it were abstract then it would follow that it is in the city's art movement." This is a Mistaken Reversal of what we can gather from the stimulus. Being abstract does not guarantee being part of the city's art movement - there could be lots of abstract paintings that are from somewhere else. Rather, being abstract is part of a necessary condition: IF a work is part of the city's movement, THEN it either has bold brushwork and sharp contract of light and shadow, OR it is abstract.

The conclusion is based on the contrapositve - IF an artwork does not have bold brushwork and sharp contract of light and shadow, AND it is not abstract, THEN it is not part of the city's art movement. The author concluded that the sufficient condition did not occur based on only one of those necessary conditions failing to occur. He must have assumed the other necessary condition also failed to occur, for if it had occurred then Blue Irises could be part of the city's art movement. Not that it must be, but that we could not prove that it wasn't.

In short, your analysis was excellent, but for one minor detail that didn't trip you up in this case. I just want to make sure it NEVER has the chance to trip you up! Good job!

Thanks for this breakdown Adam. To confirm:

PREMISES -
(Almost all paintings): city's art movement bold brushwork AND sharp contrast (of light and shadow)

(The remaining paintings): city's art movement abstract (nonrepresentational)

While this painting displays bold brushwork, it does not have sharp contrast which triggers the contrapositive

(NO bold brushwork) OR NO sharp contrast (of light and shadow) NOT IN city's art movement

Yet, the CONCLUSION has not been fully satisfied, Blue Irises NOT city's art movement

Required Assumption: Answer C)

Blue Irises NOT abstract

because of this contrapositive:

(The remaining paintings): NOT abstract (nonrepresentational) NOT IN city's art movement

[KelseyWoods]

Good job, Juanq42!

Your analysis makes sense, but we can simplify your diagramming a bit to match Adam's analysis.

Essentially the first 2 sentences tell us that the paintings in the city's art movement either have bold brushwork + sharp contrast, or they are abstract.

city's art movement (bold brushwork + sharp contrast) OR abstract

The contrapositive, then, is that if a painting does not have bold brushwork + sharp contrast AND it is not abstract, then it is not a part of the city's art movement.

(bold brushwork + sharp contrast) AND abstract city's art movement

We know Blue Irises does not have bold brushwork + sharp contrast (it's missing the sharp contrast part) but that's not enough to confirm that it's not a part of the city's art movement. We also need to know that it is not abstract. Which, as you correctly pointed out, answer choice (C) does.

Great job!

Best,
Kelsey

[salman]

Hello,

I understand the reasoning and selected the correct answer choice. But kept answer choice B as a contender as well for some time. When I apply the negation technique on both B and C the argument falls apart.

[Luke Haqq]

Hi salman!

Happy to address answer choice (B) in comparison with (C).

Before applying the Assumption Negation technique to those answer choices, let's start with the conclusion of the stimulus: "However, the most famous painting from our city—Blue Irises—cannot be considered part of the city's art movement." Why does the critic conclude this? The final sentence explains that Blue Irises has bold brushwork but lacks a sharp light/shadow contrast. The first sentence connects this contrast to the city's art movement: "Almost all of the paintings from our city's art movement share two characteristics: bold brushwork and a sharp contrast of light and shadow." However, this doesn't mean that being part of the city's art movement necessarily implies that artwork must exhibit these characteristics. Rather, the second sentence notes that some parts of the movement do not share those characteristics. Missing from the stimulus is a clear reason why the stated characteristics of Blue Irises imply that cannot be considered part of the city's art movement.

Answer choice (B) states, "Blue Irises does not depict any shadows at all." Negating this would produce: "Blue Irises depicts at least some shadows." If Blue Irises depicted some shadows, this wouldn't do anything to the conclusion that it cannot be part of the city's art movement. In addition, merely depicting shadows doesn't get to the sharp contrast aspect. So even if it depicted some shadows, one would still be left wondering why that entails that Blue Irises must not be part of the city's art movement.

Answer choice (C) gets at this. We are told that the only paintings that are part of the city's art movement that do not have bold brushwork and the light/shadow sharp contrast are abstract paintings. If Blue Irises were not an abstract painting, then it could not be part of the city's art movement because it lacks one of the essential features and isn't within the exception (it's not abstract, according to (C)). Or to explain it using the Assumption Negation technique, the negation of (C) would be: "Blue Irises is an abstract painting." If this were true, the argument that it is not part of the movement would fall apart, for it would fall within the exception given in the second sentence indicating that abstract paintings are part of the movement.

[cd1010]

Could you clarify why A is not the same as C?

My reasoning is: Stimulus says: Abstract Paintings are nonrepresentational (AP NonRep)
A says: Blue Irises is NonRep. But, this doesn't mean A is saying that Blue Irises is Abstract.
We need to cross out the possibility of Blue Irises being abstract to be able to conclude that Blue Irises does not display a sharp contrast of light and shadow.

[Chandler H]

Could you clarify why A is not the same as C?

My reasoning is: Stimulus says: Abstract Paintings are nonrepresentational (AP NonRep)
A says: Blue Irises is NonRep. But, this doesn't mean A is saying that Blue Irises is Abstract.
We need to cross out the possibility of Blue Irises being abstract to be able to conclude that Blue Irises does not display a sharp contrast of light and shadow.

Hi cd1010,

The stimulus tells us the following:

All paintings from our art movement must display light and shadow, except for abstract paintings. Blue Irises does not display light and shadow, and therefore it isn't part of our art movement.

For the stimulus's argument to make sense, we must establish that Blue Irises is not an abstract painting, and therefore does not count under that exception. Answer choice (C) tells us explicitly that it is not an abstract painting.

Now, as for answer choice (A): it tells us that Blue Irises is nonrepresentational. But does this tell us definitively whether it is abstract or not? The answer is no, because we know that all abstract paintings are nonrepresentational, but we have no reason to believe that all nonrepresentational paintings are abstract. Therefore, answer choice (A) certainly COULD be true, but it's not REQUIRED in order for the argument to work.

This seems much like what you wrote! Does this make sense?