LSAT 8 | Section 1 | Logical Reasoning: Q3

LR Question 3 Explanation

QUESTION TEXT: Sheila: Health experts generally agree that smoking…

QUESTION TYPE: Flawed Reasoning

CONCLUSION: Tim’s conclusion is that it is not true that cigarette smoking is very likely to be harmful to one’s health.

REASONING: Tim points out that his grandfather smoked quite a bit and was very healthy.

ANALYSIS: Suppose I say that most people who eat fast food are fat. You can’t disprove me by pointing out that one person who eats fast food isn’t fat. I only said most people are fat, which isn’t necessarily all.

That’s what Tim does. Sheila says smokers are probably unhealthy. Tim would need statistics to disprove that. He just gives one example.

___________

1. CORRECT. This is awkwardly worded, but it’s correct. A probabilistic conclusion is just when you say something like “it will probably rain this month.” There’s still a chance that it won’t. A counterexample is an example of something that contradicts a conclusion. A single counterexample can’t contradict a probabilistic conclusion.
2. There’s nothing wrong with disproving experts using information they didn’t have access to. If the experts had said “everyone who smokes will be unhealthy” then Tim’s argument would be good.
3. The experts did not explicitly mention Tim’s grandfather.
4. Tim actually assumed that longevity and health are related. He said his grandfather lived to be very old. He didn’t say he was healthy, but presumably he meant he was when he said he was old.
5. If the experts formed independent opinions this would strengthen Sheila’s argument (by preventing groupthink.) This isn’t the sort of thing Tim was assuming.

Recap: The question begins with “Sheila: Health experts generally agree that smoking”. It is a Flawed Reasoning question. Learn how to master LSAT Flaw questions on the LSAT Logical Reasoning question types page.