QUESTION TYPE: Flawed Parallel Reasoning
CONCLUSION: The Vegetaste Burger will probably be very successful.
- Successful product ➞ Massive ad campaign
- Vegetaste will have a massive ad campaign
ANALYSIS: The president gives us a single conditional statement, then tells us that Vegetaste meets the necessary condition of that statement.
(Technically it’s not a conditional, because it says “almost all”. But drawing it as a conditional simplifies the question).
A necessary condition never proves anything. It’s as if I said that because something has a tail, it’s a cat.
So we need another argument with one conditional statement and the necessary condition as evidence. Then the argument should incorrectly conclude the sufficient condition.
- This is a silly argument. It’s like saying “Barack Obama must be the president of some other country, because most people in America are not president”. But this is a flaw of numbers, not the flaw made in the stimulus.
- We can say that if you work at Coderight, you probably have ten years experience. Donna will probably meet this sufficient condition, but the argument concludes that she will certainly have the experience. So this is a bad argument. But it doesn’t reverse sufficient and necessary.
- This is actually a pretty good argument. If 95% of Acme’s workers are factory workers, and 95% of them oppose the merger, then at least 90.25% of Acme’s workers oppose the merger.
- CORRECT. This mirrors the structure:
President ➞ Ph.D
Robert has a Ph.DWe can’t expect Robert to become president just because he meets the necessary condition. Maybe Robert is a down-on-his-luck hobo with a Ph.D
- This is a pretty good argument. Evidence from the past can let us make probabilistic predictions about the future.
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