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

Denisse on November 19 at 12:53AM

Valid Argument Example 2

I read the explanation you gave to Kelly on this, but I still don't understand how it is invalid unless we incorporate outside information, in this case the song. So basically this section isn't like reading comprehension where you only use the info in the passage right? we can bring "outside logic", like for instance there must be at least one man named Sue somewhere out there making the argument invalid?

1 Reply

Ben on November 28 at 03:51PM

Hi Denisse, thanks for the question.

I believe that the video was demonstrating the importance of the idea "assuming that the premises are true". It was shown this way to show that if we know that the premises are not true, then the argument is invalid.

But as far as LR goes, just take whatever they say in the argument (premise-wise) as true. Don't try to prove that a premise is incorrect based on your knowledge of the real world. Worry more about how an argument is invalid based on whether or not the conclusion follows logically from the premises.
This is the concept of validity. Regardless of which premises are given, just make sure the conclusion follows.

E.g. All moons are made of cheese. My pencil is a moon.

The conclusion that follows logically will be: My pencil is made of cheese.

I tried to come up with the most ridiculous statement possible so that you see that we are concerned only with the conclusion following logically from the premises.

The only time in LR that we should really be scrutinizing the "truthfulness" of premises is if they are contradicting themselves within the argument presented.

E.g. If someone says to another: "Take my advice, don't ever take anybody's advice."

Then we will see that something is wrong with the premises and that we can't have it both ways. If I heed your advice, I am going against your advice by doing so.

Does this help? Please let me know if you have any questions.