QUESTION TYPE: Flawed Parallel Reasoning
CONCLUSION: Rosa’s dogs bark a moderate amount.
REASONING: Labrador retrievers bark a lot, and Saint Bernard’s rarely bark. Rosa’s dogs are crosses between Labrador retrievers and Saint Bernards.
ANALYSIS: This argument uses conditional reasoning, but it’s not a conditional reasoning error. Instead, this is sort of a common sense error.
You know from common sense that mixing two dogs doesn’t lead to a half and half mix on every attribute. So we can’t know how much Rosa’s dogs will bark.
To parallel the flaw, look for:
- Two statements that are conditional (i.e. if, all, every, etc.), and
- That can’t be combined predictably
Note that some things can be combined predictably. For example, if you mix water and vodka you will have half water, half vodka.
- This is tempting. But it has a “some” statement, and it also doesn’t say lack of diligence leads to very bad grades. It should have said: diligent = good, not diligent = bad, therefore somewhat diligent = somewhat good.
- CORRECT. This matches exactly. Type A = Labrador retriever. Type B = Saint Bernard. Toxicity = barking.
- The stimulus had a half-half mix for each individual dog. This should have said “Each member of the Perry family lives half in Green County, half in Winn County.”
- To match, this should have said: “Transcriptionists write shorthand, engineers write only calculus. Therefore, Bob writes half shorthand, half calculus”.
It’s a silly argument, but then so was the original.
- Just like C, this does’t combine the characteristics within a single dress.
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