QUESTION TYPE: Flawed Reasoning
CONCLUSION: Disease X surely causes high blood pressure.
REASONING: Angiotensinogen levels are correlated with high blood pressure. Disease X raises angiotensinogen levels.
ANALYSIS: This argument mixes up correlation and causation. We know that angiotensinogen is associated with high blood pressure. But that doesn’t mean it is a cause. Whenever there is a correlation, there are four possibilities:
- Angiotensinogen causes high blood pressure.
- High blood pressure causes angiotensinogen.
- A third factor causes both. E.g. maybe high blood sugar causes high blood pressure and also high angiotensinogen.
- It’s a coincidence.
If #2 or #3 are true, it’s possible that disease X could raise angiotensinogen without raising blood pressure.
___________
- This is a different flaw.
Example of flaw: High blood pressure causes fatigue. So, if someone is tired, they will get high blood pressure. - This is a different flaw. You have to translate answers and fill in words from the stimulus. “A condition” = high angiotensinogen. “an effect” = high blood pressure.
So this answer says the argument ignores this possibility: “Even if angiotensinogen levels cause high blood pressure, other factors may completely eliminate this effect and leave blood pressure no higher”.This….is not a flaw. Angiotensinogen still causes high blood pressure in this example! The fact that something is counteracted doesn’t mean it isn’t a cause.
Example of flaw: I have been shot in the chest, while wearing a bulletproof vest. Bullets kill people, so I must be dead even though I am talking. Boo!
(I am ignoring that the bulletproof vest can counteract the effect of a bullet, even though bullets do cause death normally) - CORRECT. See the analysis above. High blood pressure and angiotensinogen are correlated. The author incorrectly assumes that one causes the other. Sometimes a correlation is just random.
- This answer describes getting causation backwards. It’s a different flaw.
Example of flaw: If the cat eats the mouse, the mouse will die. So if the mouse dies, it will be eaten by the cat. - This is a different flaw, and rather complex. I’ve never seen any question use this as a correct answer. If it did happen, it would be a complex stimulus.
Example of flaw: Shouting “RUN FOR YOUR LIFE!!” often causes a stampede, and this stampede may kill people. So, it is literally impossible for shouting “RUN FOR YOUR LIFE!!” to ever directly kill someone. (The argument ignores that startling someone with a weak heart may cause a fatal heart attack, or cause them to slip and fall to their death, or something like that.)
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