Comparative Statements on the LSAT

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Comparative Statements on the LSAT:
Where Being Better Might Still Mean You Suck

If Sally is better looking than Margaret, you can’t infer that Sally is good looking. She could easily resemble Shrek and still be better looking than Margaret. However, you also can’t conclude that Margaret looks like a wildebeast. Margaret might be the second best looking Victoria’s Secret model. Right behind Sally, of course.

If Walter receives a better score on his biology exam than he did on his calculus exam, he could have received an A+, a C, or an F. The general population generally believes that rocky road ice cream tastes better than broccoli, but does that mean that everyone loves rocky road ice cream? Not necessarily.

These situations might seem intuitive at first, but this distinction is the basis for many fallacies on the LSAT. Comparative or relative statements have been used repeatedly on recent tests to tempt students to draw invalid inferences, and thus err in finding that elusive correct answer.

As you can see from the examples above, claiming that one thing is better than something else, or that one factor is more important than another, does not tell you very much. If salsa X is spicier than salsa Y, students will normally infer that this means that salsa X is very spicy and salsa Y is not spicy at all. That could be the case. But it also could be true that both X and Y are incredibly, light-your-mouth-on-fire spicy. Or it could also be true that both are about as spicy as mayonnaise.

Here are two recent examples that confused students:

1. Taxes

A recent weaken question discussed the relationship between taxes on cigarettes and smoking. Unsurprisingly, the argument concluded that imposing a stiff tax on cigarettes would reduce the number of people that smoke. Great news.

A tempting sucker choice stated the following:

People are less likely to discontinue an activity if the price of that activity increases due to taxes than for a different reason.

This was a very popular answer choice. Students took this to mean that people are not likely to stop doing something (smoking) if the price goes up due to taxes. But that is not what the answer choice says. It simply states that people are less likely. That means that the chances that people stop smoking could be 1%, 50% or 99%. And that means this answer doesn’t do bupkis for us.

2. Moon

Another vexing question investigated the idea of building colonies on the Moon. Sweet idea, I know. The argument went on to conclude that such colonies would be built. This was a flaw question and the flaw was found squarely in one comparative statement.

Due to overcrowding on Earth, there is a growing incentive to build colonies on the Moon.

Sure, there is a growing incentive. There is also a growing incentive to sleep in a hyperbaric chamber (like the King of Pop) because air pollution is getting worse. But I’m not actually going to do it. A growing incentive implies that there is more of a reason that before, but that could mean the chances of actually building a colony on the Moon are 3% or 88%.

What’s the lesson to be learned? Watch out for comparative or relative statements, and make sure not to misinterpret them. After all, you don’t just want to do better than the next guy, you actually want to do well.

4 Responses

  1. Ashley says:

    I believe you made a mistake on one of your examples: “If Walter receives a better grade on his biology exam than he did on his calculus exam, he could have received an A+, a C, or an F.”
    Walter could not receive an F on his biology exam, assuming an F is the lowest possible grade. If he receives an F on his biology exam, then there is no way for him to receive a better grade on his biology exam than on his calculus exam. What would be possible is for him to get the same grade, F, or do better on his calculus exam.

  2. Jake Flannagan says:

    The excellent answer, I congratulate :(

  3. Adam says:

    I still believe the example works. He could have received a grade of 40% on his biology exam and 35% on his calculus…both are still F grades but the biology exam grade is till higher.

  4. Anonymous says:

    “People are less likely to discontinue an activity if the price of that activity increases due to taxes than for a different reason.”

    Don’t you mean, more likely?

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