LSAT 123 | Section 2 | Logical Reasoning: Q2

LR Question 2 Explanation

QUESTION TEXT: All Labrador retrievers bark a great deal. All Saint Bernards…

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.

___________

1. 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.
2. CORRECT. This matches exactly. Type A = Labrador retriever. Type B = Saint Bernard. Toxicity = barking.
3. 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.”
4. 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.
5. Just like C, this does’t combine the characteristics within a single dress.