Flaw Questions - Assumptions Answer Choices

[Emmeline Ndongue]

In flaw questions, do assumptions answer choices have to be "necessary" assumptions to be the correct answer? Can "sufficient" assumptions answer choices also be the correct answer?


It seems that if the answer was about sufficient assumptions, it'd be incorrect. Is it because for an argument to connect with its premise, you only need "necessary" assumptions rather than "sufficient" ones?

[christine.defenbaugh]

Thanks for the question, Emmeline!

As a general matter, yes, the assumption pointed to in a flaw answer choice will be a necessary assumption. These answer choices come in the format of:

• "flawed because it presumes, without providing justification that..."
• "flawed because it takes for granted that..."
• "flawed because it assumes that..."

If you think about it, when we accuse an argument of being flawed, we are accusing the author of making some inappropriate step in logic. It wouldn't be right to accuse someone of something they didn't do, so we should only accuse the author of something we know for certain s/he was thinking. The only things I know for certain they had to have been thinking are the assumptions that are necessary for the argument to work.

As a result, we would want to avoid any big overkill, very sufficient-but-totally-not-necessary assumptions in these answer choices.

Now, it's worth pointing out here that many, many, many assumptions on the LSAT are actually both 'necessary' and 'sufficient' at the same time. These are perfectly appropriate for flaw answer choices, because all we care about is the fact that they are needed for the argument.

I hope this helps!

[Emmeline Ndongue]

It really helps. Appreciated for the clarification!