• Nathan Fox

Let's Break Down Sufficient Assumptions

Test 0 - Question 2 - Question 15

Logical Reasoning

Difficulty: 3


Sufficient Assumption questions, done properly, are all about predicting the answer before getting bogged down in the wrong answer choices. On these questions, your task is to WIN the case for your client. This means connecting the evidence and conclusion in a way that makes the conclusion fact. There's usually only one way to get there. Cover up the answer choices with your hand if you need to. You've gotta be the boss of the test on this one. 

The pertinent evidence is "Each year's vaccination will protect only against the strain of the influenza virus deemed most likely to be prevalent that year."

The conclusion we're trying to reach is "Every year it will be necessary for all high-risk individuals to receive a vaccine for a different strain of the virus."

My extremely formulaic prediction is a bridge between the evidence and the conclusion: "Every year, there will be a different strain of influenza virus deemed most likely to be prevalent."

Do you see how that prediction, when combined with the evidence, will PROVE the conclusion as fact? Do you feel it click? You need to feel it click. It makes perfect sense, and it's predictable. You can do this. 

Now watch how easy it is to slice through the answer choices:

A) What? Who cares? This doesn't bridge the evidence and the conclusion. B) Irrelevant. Don't care.  C) This is simply restating a premise. We already know that each year the vaccine will protect only against the strain of virus deemed to be most prevalent. So obviously it's not going to protect against more than one strain. This answer does nothing. D) It's a clunky way of saying it, but this is a perfect answer. This answer has the exact same effect as "every year there will be a different strain deemed most likely to be prevalent." This answer, when true, proves the conclusion. Do you feel it click? You gotta feel it click. This is a perfect answer. Sufficient Assumption questions are so, so easy once you learn to feel that click.  E) Side effects? Get out of here. Who cares? The wrong answer choices here are really, really wrong. There's only one answer that makes the argument win. The other answers aren't even close.

Get more of these explanations from the LSAT Demon


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