LSAT 124 | Section 2 | Logical Reasoning: Q7

LR Question 7 Explanation

QUESTION TEXT: In Western economies, more energy is used to operate buildings…

QUESTION TYPE: Necessary Assumption

CONCLUSION: 50-100 years from now, energy efficient building materials will save over $200 billion per year.

REASONING: They currently save a few billion dollars per year.

ANALYSIS: This is the worst LSAT argument I’ve come across in a while. It starts with a long intro that tells us nothing except that energy efficient buildings are saving us several billion dollars per year.

It then concludes that in the future, they will save us much more money. There are a ton of necessary assumptions here:

1. We’ll keep building improvements.
2. Energy costs will stay about the same, or increase.
3. We’ll still use as much energy as we do now.
4. We can form predictions of what the future will be like 50-100 years from now (we can’t).
5. And so on.

The first one is the correct answer.

___________

1. CORRECT. If it becomes prohibitively expensive, we’ll stop adding it to buildings. So our savings won’t increase, and the argument fails.
2. An oil crisis isn’t necessary. As long as energy prices remain at least at their current level, there will be savings.
3. That isn’t necessary. We could build a lot more buildings and have more consumption, but still save billions because all of those buildings have efficient technology. We would use even more energy if they weren’t efficient.
4. “Savings” doesn’t mean spending is lower. It means we spend less than we would have spent without the savings.
5. Not necessary. Even current technologies will produce savings.

Recap: The question begins with “In Western economies, more energy is used to operate buildings”. It is a Necessary Assumption question. Learn how to master LSAT Necessary questions on the LSAT Logical Reasoning question types page.