Logical reasoning PrepTest 114 · Section 4 · Question 18

Correct. Argument or Facts:
Argument/Argument

Valid or Flawed:
Flawed/Flawed

Question Type:
Argument Evaluation

Stimulus Summary:
A: The brain's structure is important to thinking, so researchers should base their computers designed to think on that structure.

Y: That's like saying planes should be built like birds, which doesn't work
Thus - Computers structured like brains are likely to fail
And therefore - They should focus on the function, not the structure, of the brain

Answer Anticipation:
Yang's argument reaches a rather one-sided conclusion—focus on function and "ignore" structure. While Yang does use an analogy to show that structure isn't always inherent to a given function, she doesn't show that the structure can be entirely ignored. After all, that structure does result in the desired function.

In order to evaluate this argument, then, it'd be helpful to know if looking at structure—even if it isn't going to be used directly in a design of a thinking machine—might help researchers learn something about how to create such a machine.

Answer Explanation:
Yang recommends focusing solely on function and "ignor[ing]" structure in her conclusion. While a structure developed by nature to achieve a certain function might not be necessary to achieve that function, it's possible something could be learned by studying the structure, as this answer choice states. An answer to the question suggested by this answer would help to evaluate whether the physical structure of the brain should be ignored in the research aimed at making a thinking machine, so this is the correct answer.

Key Takeaway:
Whenever an argument features an extreme conclusion—e.g., something should be ignored—it's almost certainly stronger than the premises supporting it. If you can find a single reason why that extreme conclusion wouldn't hold, then you've identified a flaw.

Incorrect. The debate is over whether the structure of the brain includes something essential to thinking, not what type of thinking is involved.

Incorrect. The time spent developing something isn't relevant to whether the development is focused on the right things.

Incorrect. What is being done is out of scope of Yang's argument about what should be done.

Incorrect. "Some" failures don't matter to the argument—the question is whether anything could be learned by looking at the physical structure.