Logical Reasoning

PT107 · S1 · Q15 Ordinary mountain sickness, a common

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Ordinary mountain sickness, a common condition among mountain climbers, and one from which most people can recover, is caused by the characteristic shortage of oxygen in the atmosphere at high altitudes.

Conclusion

Cerebral edema is especially dangerous at high altitudes.

Evidence (since)

Cerebral edema has symptoms that are very similar to ordinary mountain sickness, which occurs at high altitudes.

And if you don't correctly treat cerebral edema from the onset, it can quickly become life-threatening.

Evaluate

It might take a few reads to understand the argument.

It sounds like cerebral edema is dangerous no matter where it happens, because it can quickly become life-threatening if it's not correctly treated at its onset.

So why does the author think it's especially dangerous at high altitudes? She is apparently worried that at high altitudes, we might confuse it for ordinary mountain sickness, which has the same symptoms and occurs at high altitudes.

If you were at sea level, a doctor would look at your symptoms and think, and they would probably guess cerebral edema, since it makes no sense to have the high altitude - caused mountain sickness if you're at sea level.

But if you were at high altitudes, someone might diagnose your symptoms as ordinary mountain sickness.

Goal

So overall, we want to look for an answer that spells out some part of the storyline the author is envisioning: people might be at high altitudes and have cerebral edema, but the medical folks trying to treat that person assume she has ordinary mountain sickness, and so they don't give her the correct treatment for cerebral edema, so the cerebral edema quickly becomes life threatening.

15.

Which one of the following is an assumption on which the argument depends?

  1. Correct

    The treatment for ordinary mountain

    Why this is right

    Was the author thinking that someone with ordinary mountain sickness gets a different medical protocol than does someone with cerebral edema? Yeah, I guess he was! I mean, he's worried about the idea that at high altitudes the medical staff will confuse your cerebral edema for regular ol' mountain sickness and they'll treat the latter rather than the former. If we negate this answer, it becomes a big objection: "Hey, author --- it doesn't actually matter if they confuse our cerebral edema for ordinary mountain sickness. After all, the treatment for ordinary mountain sickness is identical to the treatment for cerebral edema. They're not different. So whether they think we have cerebral edema or ordinary mountain sickness, they'll give us treatment X. Thus, it doesn't make sense to say that cerebral edema is especially dangerous at altitudes where it could be confused with ordinary mountain sickness."

    Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.

    65% picked this

  2. Cerebral edema can cause those

    Out of Scope: Coma

    The author has only committed to the idea that cerebral edema can be "quickly life-threatening, if not correctly treated". She hasn't committed to believing any specific symptoms of cerebral edema (like a coma) once it gets to its dangerous stage.

    3% picked this

  3. Unlike cerebral edema, ordinary mountain

    Too Strong: No Disruption

    The author doesn't need to assume that cerebral edema and ordinary mountain sickness don't have this symptom in common. She only needs to assume that, "if a doctor thinks you have ordinary mountain sickness, they won't give you the correct treatment for cerebral edema". If we negated this answer and said, "Hey, author -- people with ordinary mountain sickness also get disruption of blood circulation in the brain", it wouldn't hurt the argument. He would say, "Sure, but that ailment can be treated with simple oxygen infusions. Cerebral edema, meanwhile, needs to be treated as soon as possible with a high dose of potassium (for example)."

    17% picked this

  4. Shortage of oxygen at extremely

    Out of Scope: Errors of Judgment

    This answer seems to be an Outside Knowledge trap. Being deprived of oxygen does indeed have these effects, in the real world. But that has nothing to do with the logic of this argument. The argument would be the same if shortage of oxygen caused you to suddenly speak with an Irish accent. The author only needs to assume that, "If someone might confuse your cerebral edema with ordinary mountain sickness, then you're less likely to get your cerebral edema correctly treated from its onset". This answer doesn't fall anywhere into that idea.

    8% picked this

  5. Most people who suffer from

    Out of Scope: Recover Without Treatment

    We're told that most people can recover from ordinary mountain sickness, but it doesn't say they recover without any special treatment. Would it hurt the argument if most people did need special treatment to recover from ordinary mountain sickness? No, it would only hurt the argument if the special treatment people needed for ordinary mountain sickness was the same as the special treatment for cerebral edema.

    8% picked this

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