LSAT 11 | Section 2 | Logical Reasoning: Q15

LR Question 15 Explanation

QUESTION TEXT: A standard problem for computer security is that passwords …

QUESTION TYPE: Flawed Reasoning

CONCLUSION: If the trial result can be repeated operationally, there will be a way to give access only to authorized users.

REASONING: A new voice recognition system was tested in a trial, and it never incorrectly granted access to unauthorized users.

ANALYSIS: Notice what the conclusion says. It doesn’t just claim that unauthorized people are kept out. It claims the system gives access to those who are entitled and no one else.

But the evidence only mentions that the system didn’t incorrectly accept unauthorized users. It says nothing about how it performed when authorized users tried to get in. What if it denied everyone?

___________

1. Not the issue. The argument is explaining why it’s turning away from passwords, not making an invalid comparison.
2. This is the trap. Yes, the trial is small but the author already qualifies the conclusion (“if the results can be replicated”). So they’re conditional in their claim, not overgeneralizing from little data.
3. Irrelevant. The argument is only about computer security. No other applications matter.
4. CORRECT. The conclusion claims the system will allow access only to entitled users, but the trial only tested unauthorized users. So it ignores the possibility that authorized users might be wrongly rejected.
5. Actually the opposite. The conclusion is reasonably cautious. It’s the incomplete evidence that’s the flaw, not an overstatement.