Reply To: Inference

June 5, 2017 at 11:18 pm #3114
LSAT Dan
Participant

In a “Must Be True” question, there won’t be a gap between the between the support (premises) and conclusion; you shouldn’t expect to find a conclusion in the passage – either there won’t be one, or it won’t be relevant to answering the question. The correct answer will, essentially, be a conclusion. Not necessarily “the” (main) conclusion, but something that could be concluded.

To see this more clearly, let’s consider a closely related question, the sufficient assumption question. Sufficient assumption questions and Must Be True questions both typically use conditional logic, but in the assumption question, it’s a premise that’s missing. Let’s use a simple but complete argument for reference:
P1) Anyone who is in the military is entitled to half-off hamburgers at Bob’s.
P2) Sam is in the military.
C) Sam is entitled to half-off hamburgers at Bob’s.

The sufficient assumption question might be:

“”Anyone who is in the military is entitled to half-off hamburgers at Bob’s. Therefore, Sam is entitled to half-off hamburgers at Bob’s.

Which one of the following, if assumed, allows the conclusion to be properly drawn?”

Here’s where we have that gap you were talking about – in an *assumption* question, where what’s missing is a premise. The right answer, of course, is “Sam is in the military.”

But the inference question looms like this:

“Anyone who is in the military is entitled to half-off hamburgers are Bob’s. Sam is in the military.

If the above statements are true, which of the following must be true?”

There’s no gap in the logic here. In fact, there’s no conclusion here – just two statements, i.e. Potential premises. The right answer this time IS the conclusion of the potential argument: “Sam is entitled to half-off hamburgers at Bob’s.”

Hope this helps.

-Dan