LSAT-Section-1-Logical-Reasoning Section One : Logical Reasoning - Practice Questions

Question 247

During the three months before and the three months after a major earthquake in California, students at a college there happened to be keeping a record of their dreams. After experiencing the earthquake, half of the students reported dreaming about earthquakes. During the same six months, a group of college students in Ontario who had never experienced an earthquake also recorded their dreams. Almost none of the students in Ontario reported dreaming about earthquakes. So it is clear that experiencing an earthquake can cause people to dream about earthquakes.

Which one of the following, if true, most strengthens the argument?

Select an option, then click Submit answer.

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Before the California earthquake, no more of the students in California than of those in Ontario recorded dreams about earthquakes.
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The students in California were members of a class studying dreams and dream recollection, but the students in Ontario were not.
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Before they started keeping records of their dreams, many of the students in California had experienced at least one earthquake.
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The students in Ontario reported having more dreams overall, per student, than the students in California did.
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The students in Ontario who reported having dreams about earthquakes recorded the dreams as having occurred after the California earthquake.

Reference / correct answer:

Before the California earthquake, no more of the students in California than of those in Ontario recorded dreams about earthquakes.

Isn’t there a song “California Dreaming”? We don’t think this is what they had in mind. We need to strengthen the argument that experiencing an earthquake can cause people to dream about earthquakes. The evidence is that almost none of the students in Ontario, who never experienced an earthquake, dreamt about earthquakes, while half the Californian students did dream about earthquakes after going through a major quake. Well, we know that we can weaken a causal argument by severing the link between the supposed cause and the effect, and one way to do that here is to show that students from California dreamed about earthquakes before the big one hit. Then it wouldn’t seem as likely that experiencing the quake caused the dreams. (Maybe something else, like media coverage from previous quakes, keeps Californians – even those who haven’t personally experienced one – dreaming of quakes all the time…) Since this would damage the argument, the author assumes that they didn’t dream much about quakes before the one in question, and the argument would be strengthened if this assumption were bolstered. Choice option [Before the California earthquake, no more of…] accomplishes this. The Ontario group is the control group, so if the Californian dreams prior to the quake were similar to the Ontario dreams (almost none about earthquakes), then the possible alternative discussed above is discounted, the author’s assumption is shored up, and we’d be more likely to believe the conclusion in the final sentence.

Question 248

It is wrong to waste our natural resources, and it is an incredible waste of resources to burn huge amounts of trash in incinerators. When trash is recycled, fewer resources are wasted. Because less trash will be recycled if an incinerator is built, the city should not build an incinerator.

Which one of the following can be properly inferred from the statements above?

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All of the city's trash that is not recycled goes into incinerators.
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By recycling more trash, the city can stop wasting resources entirely.
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The most effective way to conserve resources is to recycle trash.
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If the city is to avoid wasting resources, huge amounts of trash cannot be burned in any city incinerator.
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If the city does not burn trash, it will not waste resources.

Question 249

Human intelligence is not possible without human emotions. A computer is something that can never have emotions, so for that reason alone a computer will never be able to display intelligence.

Which one of the following is an assumption on which the argument depends?

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A computer could have emotions only if it could display intelligence.
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Computer technology will not greatly advance beyond its current state.
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Someone or something is intelligent only if it can identify its emotions.
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The greater the capacity to feel emotions, the more intelligence there is.
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Being intelligent requires the capacity to have emotions.

Reference / correct answer:

Being intelligent requires the capacity to have emotions.

Did you pick up on the scope shift in this Assumption question? Did you notice the mismatched terms? If not, take another look before reading on. Hint: look closely. Okay:

Human intelligence requires human emotions. A computer can’t have human emotions. Therefore, a computer can’t display human intelligence. What’s wrong with that?

Nothing – but that’s not what the author says. She concludes that computers can’t display intelligence period; she leaves out the word “human,” and therein lays the shift. What if there are other kinds of intelligence that don’t require emotions? Then the author couldn’t argue that computers can never display intelligence based solely on the fact that they don’t have emotions. If the author wants to make a case about intelligence in general based on the evidence given, then she needs the connection cited in option [Being intelligent requires the capacity to…]. (Note: If you missed the distinction between human intelligence and intelligence in general, option [Being intelligent requires the capacity to…] probably looked to you like a restatement of the first sentence.)

LSAT-Section-1-Logical-Reasoning – Section One : Logical Reasoning