Which one of the following statements most accurately characterizes a difference between the two passages?

Esther on June 5, 2018

example 2 versus example 1

how does one show if a premise is false? for example example 2. I have never met a man named sue. How am I supposed to know a man named sue exists

3 Replies

Mehran on June 5, 2018

@esther the correct answer choice would have to say something along the lines of, "There is a boy named Sue" or "Not all people named Sue are girls."

This is precisely why we say you want to assume all premises are true. Because if a correct answer choice takes issue with the truth of a stated premise, it will be very obvious.

Hope that helps! Please let us know if you have any other questions.

Esther on June 5, 2018

I'm still confused.
Im still not understanding how example 2 was invalid if we are to assume all premises are true

Christopher on June 6, 2018

@esther Part of this comes down to the way the test is designed. Essentially, the test is entirely self-contained. That means that on the example you asked about, if there is nothing in the question that references Johnny Cash's music or any factual man named Sue, then the argument is valid. However, if the question provides information that casts doubt on the validity of a premise, then you can question it, but that's going to be fairly obvious. So, in short, you're not going to have questions like example 2. Either that argument is valid, or there would be an explicit counterpoint that challenges a premise. This is going to play out differently in different question types, but on any given question, remember that the only information that matters is the information that is on the page. Does that clear it up at all?