- Thu Dec 29, 2022 6:23 pm
Great question! The goal of the assumption negation technique is to help you imagine what the argument would be like without the potential assumption. So, when you negate the answer choice, you want to put it back in the argument in the negated form. What happens to the argument with the negated assumption? Does it hurt the conclusion? Does it help the conclusion? Does it have no impact on the conclusion? You are looking for an answer choice that hurts the conclusion of the argument when it's negated.
Let's look at how it would work in a simple argument.
Premise: Socrates is a man
Conclusion: Socrates is mortal
Imagine the following possible answers:
(A) Socrates has two legs
(B) Some men live forever
(C) All men are mortal
If we negate answer choice (A), we get that "Socrates does not have two legs." Putting that back into the argument we'd struggle to connect that fact to the conclusion. Answer choice (A) is an example of a no-impact answer. It doesn't impact the conclusion either way.
If we negate answer choice (B) it would say "no man can live forever." If we insert this negation into the argument, we actually support the conclusion. If no man can live forever, and Socrates is a man, that must mean he's mortal. BUT remember, this is the negation that supports the conclusion. That means this is an incorrect answer choice. The absence of the answer choice helps the argument. The answer choice itself does not help the argument.
If we negate answer choice (C), it would say "not all men are mortal." This would hurt the argument. The only thing we know about Socrates is that he is a man. If not all men are mortal, we can't conclude from the fact that Socrates is a man means he's mortal. This makes it less likely that he's mortal, so it hurts the conclusion. The absence of this answer choice hurts the argument, so this is the answer choice we are looking for.
Overall, I highly recommend trying out the negation technique will all answer choices in practice. You'll get a better sense of what it looks like when the negation has no impact on the argument, when it helps the argument, and when it hurts the argument.
Hope that helps!