PrepTest 159, Section 3, Question 13
Every human's brain contains a mental representation of(43 more words not shown)
Which one of the following(9 more words not shown)
- AThe human brain's(9 more words not shown)
- BThe external world(10 more words not shown)
- CThe human brain(10 more words not shown)
- DThe human brain(8 more words not shown)
- EIt is impossible(13 more words not shown)
Reading the argument
I don't know where you're sitting. A coffee shop? Your house? A boat? My mental picture of the world plainly doesn't contain every detail about it.
So I'm comfortable with the idea that the brain's representation is incomplete. I'm less sure about the general rule offered to support it: why couldn't a smaller object represent something larger and more complex? Could a sophisticated computer model a much larger system? That's a question worth asking, even though imagining a model doesn't establish that it represents every detail.
What we’re looking for
For the conclusion question, ask what those reasons are meant to establish. The statements after “After all” support the earlier claim that the brain's representation leaves out detail. That is the answer I'd predict. The world's size and complexity and the rule about what smaller objects can represent are reasons to accept that claim. We can identify the point they support without agreeing that those reasons are convincing.
Working the answers
- ACorrect
This is the point the rest of the argument supports. The author appeals to the relative size and complexity of the world and brain to explain why the brain's representation leaves out much detail. A states that conclusion directly.
- B
This is a reason for the conclusion. The world being larger and more complex matters because the author combines it with a general rule about what objects can represent. The resulting claim is that our mental representation leaves out detail.
- C
This applies the author's general rule to the brain: the brain can't completely represent something larger and more complex. That supports the conclusion about its representation of the external world. It isn't the final claim about how much detail that representation leaves out.
- D
This gives the starting point: the brain has a representation of the world. The author then goes beyond the representation's existence to argue that it is incomplete. D leaves out the claim being established.
- E
This is the broad rule offered as support. We might question it, but a questionable premise doesn't become the conclusion merely because it draws our attention. The author uses this rule to reach the narrower point about the human brain's picture of the world.
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