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

Andrew on April 5, 2018

Intro to logical reasoning valid arguments

I have a question about the second argument. Anyone named Sue is a girl. X is named Sue. X is a girl The question I have is you initially call it a valid argument, you assume the premises to be true however when you introduced the Johnny cash song (which no song will be occurring on the LSAT) you change it to a flawed argument. However you call it a flawed argument, I thought the purpose of this section was to determine if the arguments were valid (good) or invalid (bad). However you are introducing that the argument is flawed with a SONG - which is never going to occur on the LSAT. We assumed the premise to be true, and it was a valid argument before the johnny cash song, however there will not be a johnny cash song playing on the LSAT, what benefit does playing the Johnny Cash song have in determining whether or not it is valid or invalid? (NONE) I thought that was the purpose here, not to go off on some tangent about it being flawed or not with a song which will never occur on the LSAT. So is it a valid argument that is flawed? Or just a flawed argument that isn't valid anymore because it is flawed. Also the third example. (It is cold. It will snow) I understand that it is an invalid argument because the conclusion does not follow logically. But why is it flawed? And what is the purpose of talking about flaws this early it only has confused me.

1 Reply

Austin on May 13, 2018

Hi Andrew, the way I understood it was that an argument is valid if the conclusion follows the premises logically, if we assume that everyone named sue is a girl and x is named sue logically were lead to believe that x is sue, however by using the song to show that not everyone named sue is a girl we know that while the argument is VALID because it follows logically it is FLAWED because because the premise is false.

In example 3 its an invalid argument because the conclusion doesn't follow logically from the given premises, just because its cold doesn't mean its gonna snow. If the premises were "when its cold in X it snows, X is cold" and the conclusion was "it is snowing in X" then we are logically led to believe that its cold where X is.
That's how I understood it hope it helps.