PrepTest 154

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Stimulus Summary:
An engineer says unintended airbag deployment sometimes causes injuries, so automakers are inventing complex computerized systems to control air bags and hopefully prevent these injuries. But the more complex a computerized control system for air bags is, the more ways it can fail. Therefore, the attempts to fix this problem will only make it worse.

Answer Anticipation:
Does "there are more ways the thing can fail" actually equal "the thing is more likely to fail"? If we build a simple test rocket that can only fail by exploding mid-air, but does so 50% of the time, is it actually more likely to fail than a complex space shuttle with a million possible points of failure, that only fails on 1 in 100 launches? This is an equivocation between the possible modes of failure and the likely rate of failure, in other words, a percent vs. numeral fallacy.

Answer Explanation:
Yep, right away this calls out the central problem with this logic. Something could have more possible ways to fail without actually being more likely to fail. If you took time to anticipate, you were immediately rewarded!

Key Takeaway:
Fallacies involving equivocation between two related but different concepts are an LSAT favorite. You can only use statistics about one thing to draw conclusions about exactly that thing, not about something kinda related but fundamentally different. In this case there's also a percent versus number issue, again a common concept on the LSAT. When analyzing any stimulus, keep a watchful eye out for conclusions that are based on data about something that is not precisely the same as the subject of the conclusion.

Incorrect. The argument hasn't committed this particular fallacy. The engineer just says that the complex computer systems will make the problem worse. They don't say "and with each failure, air bags will deploy accidentally."

Incorrect. The engineer's conclusion doesn't require specifically addressing non-computer related failures, because the conclusion is about the rate of accidental inflation, not about the rate of computer errors. In order for the engineer's prediction to be correct, the rate of accidental inflations just needs to go up; it doesn't matter if such inflations are all tied specifically to computer failures or not.

Incorrect. It wouldn't be fallacious to ignore this possibility, since the engineer's conclusion doesn't say "therefore, there is no advantage to continuing to develop these computer systems." Our author is only talking about the rate of accidental inflations, not about the overall value of the systems.

Incorrect. The engineer isn't trying to second-guess the necessity of air bags in vehicles! They just don't think ever more complex computer systems are going to reduce accidental inflations.