LSAT 158 | Section 2 | Logical Reasoning: Q21

LR Question 21 Explanation

QUESTION TEXT: A geologist recently claimed to have discovered …

QUESTION TYPE: Weaken

CONCLUSION: Nanobes are probably not living things.

REASONING: They’re too small to contain a reproductive mechanism, which is required for life.

ANALYSIS: The whole argument depends on: if something is too small to contain a reproductive system, then it can’t be alive.

So that’s where you should focus. The author is assuming that a living thing must itself physically contain the machinery needed to reproduce.

Maybe something can still count as living even if it doesn’t have a reproductive system. Maybe reproduction is happening in a different way than the author is imagining.

___________

1. This doesn’t help much. It tells us some bacteria don’t reproduce sexually, but the argument never said reproduction had to be sexual.
2. CORRECT. This shows that reproduction can still happen even if the nanobe doesn’t individually have its own reproductive mechanism.
3. Even if alleged Martian bacteria are the same size, that doesn’t show nanobes can reproduce.
4. This is tempting, but too vague. Saying earlier definitions used worse microscopes does not show that reproductive mechanisms are not required for life.
5. Size and simplicity are not the issue by themselves. The argument is specifically about whether something that small could reproduce.