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

Lamis-Youssef on March 31, 2019

Valid and invalid arguments

Do we assume the premises are true because they gave us that information or do we question the premises ? I.e in example #2, the conclusion follows the premises perfectly but it is still invalid because IN GENERAL we know that a boy could be named sue?

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Ravi on May 10, 2019


Great question. Mehran uses the 'Girl named Sue' reference to
illustrate one way that an argument can be attacked (attacking the
premises by claiming or showing one or more of them to be false).
However, as Mehran notes, if we assumed the premises in that example
to be true, it's a valid argument. The argument only becomes invalid
when we find that one of the premises is false.

For the purposes of the LSAT you always want to assume the premises
are true. The way you're attacking the arguments in the LSAT is to
show why, even if we assume the premises to be true, the conclusion
doesn't necessarily follow.

Does this make sense? Let us know if you have any more questions!

KK. on May 12, 2019

If I understand this correctly and #2 was an LSAT question, #2 would be a valid argument because we are assuming the premises are correct?