LSAT 140 | Section 4 | Reading Comprehension: Q24

RC Question 24 Explanation

DISCUSSION: You might think that the point of the passage is to compare two theories of mirrors. But the field-of-sight theory is only mentioned to establish that we have a pretty good explanation of mirrors. After the first paragraph, the field-of-sight theory is not mentioned again.

Instead, the rest of the passage discussed the front-to-back theory. The main point of the passage is that the front-to-back theory is not satisfactory. This is because it doesn’t consider what happens when we look into mirrors (last two sentences of para. 4).

___________

1. The passage doesn’t give any evidence against the field-of-sight theory. It appears the author agrees that this theory is correct.
2. This is a tempting answer, but the front-to-back theory is not based on empirical evidence. We use our mental constructs to imagine the front-to-back theory (the second sentence of paragraph 3), but these constructs are contrary to fact (paragraph 3). The front-to-back explanation is based on a false idea.
3. Second-to-last sentence of paragraph 4 did mention two necessary conditions for an explanation of mirrors, but this is not the same as listing difficulties that need to be overcome. A difficulty is a specific obstacle that needs to be removed, for instance “we need to construct a physically perfect mirror” or “we need to figure out a way to measure light entering a mirror”.
4. CORRECT. Paragraphs 2-4 are dedicated to showing why the front-to-back theory is inadequate. See the passage analysis section and the discussion above for more details.
5. The passage does explain why the front-to-back theory is accepted. But it is not because of theoretical support. Instead, the front-to-back theory receives support for two reasons:
    
   1. The front-to-back explanation seems natural to us, due to the way we imagine mirrors (paragraph 3)
   2. Scientists like to separate the observer from the phenomenon (first sentence of paragraph 4)