LSAT 72, Logical Reasoning II, Q22, LSATHacks

LR Question 22 Explanation, by LSATHacks

QUESTION TEXT: A recent study revealed that people who follow…

QUESTION TYPE: Flawed Reasoning

CONCLUSION: The recommendations for avoiding pathogen infection must be wrong.

REASONING: Those who follow all the recommendations are more likely to get sick.

ANALYSIS: I’ve seen this flaw occur a few times on recent LSATs. You should commit it to memory. The key is that the argument didn’t ask why one group followed the instructions precisely, and the other didn’t. Maybe the group that followed the instructions precisely has a higher risk: weaker immune systems, eats meat more regularly, has less sanitary meat, etc. In that case, precautions could help, even if they don’t eliminate the problem.

The argument is trying to fool you into thinking this is a scientific experiment, where people are divided into two groups and we test the influence of one factor. But that’s not what happened. People may be more likely to fall into the “takes precautions” group if they are at risk. Since there’s no randomness in group choice, this isn’t a controlled experiment. 

___________

1. The argument is only talking about infections from meat. Other foods are irrelevant.
2. It doesn’t matter how many people follow the instructions. The argument was making a claim about what happens to the entire group that follows instructions. It doesn’t matter if that’s 1,000 people or 100,000,000.
3. This answer is trying to convince you that some diseases can’t be detected, and therefore the study missed them. It’s trying to contradict a premise. That almost never happens.
   Also, the premise didn’t say the meat instructions group had more “symptoms” of diseases. It said they have more diseases, period. We don’t know how this was measured, but presumably it was accurate. (e.g. via blood tests).
4. This contradicts the stimulus. Some people followed the instructions yet still got sick.
5. CORRECT. This suggests that people take precautions because they know they may get sick. In that case it’s possible the precautions help, even though they don’t eliminate the problem. 

Hi, I'm Graeme Blake

Founder of LSAThacks; I scored a 177 on the LSAT.

I created the LSAT Mastery Seminars, which are part of the Ultimate LSAT Prep Bundle

If you like the explanations you're reading I'm 100% confident you'll enjoy the courses. Satisfaction guaranteed.

---------
Updates:

For updates, sign up for my email list. I update whenever I have new posts.