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WFT? One statement contains, "If, either, or" HELP!

Posted: Sun Oct 10, 2010 11:01 pm
by youknowryan
This one threw me for a loop since it has three indicators in it.

It is clear that if Bob's dismissal was justified, then he was either incompetent or late.


Do I treat it like a standard "or" statement?

dismissal justified -> late or incompetent


Or do I treat it like an either/or statement?

not incompetent (dismissal not justified) -> late (dismissal justified)

not late (dismissal not justified) -> incompetent (dismissal justified)


I am leaning toward the second option. Thoughts?

Re: WFT? One statement contains, "If, either, or" HELP!

Posted: Sun Oct 10, 2010 11:13 pm
by ziggie
dismissal justified -> late or incompetent

or you can also write it as

not late AND not incompetent -> dismissal NOT justified

Re: WFT? One statement contains, "If, either, or" HELP!

Posted: Sun Oct 10, 2010 11:32 pm
by youknowryan
Any one able to confirm this? THe "either" part is what still has my attention.

Re: WFT? One statement contains, "If, either, or" HELP!

Posted: Mon Oct 11, 2010 12:15 am
by kilgoretrout103
Ziggie is right.

Formal logic:

-J -> (I v L)

Contrapositive:

(-I & -L) -> J

J = Bob's dismissal was justified
I = incompetent
L = late

And "v" is a vel meaning "or."

EDIT: "Either" still means "one or the other, or both." Every "or" on the LSAT is inclusive, unless they explicitly say "This and that and not both."

Re: WFT? One statement contains, "If, either, or" HELP!

Posted: Mon Oct 11, 2010 1:35 am
by youknowryan
kilgoretrout103 wrote:Ziggie is right.

Formal logic:

-J -> (I v L)

J = Bob's dismissal was justified
I = incompetent
L = late

-J = justified or NOT justified?

Re: WFT? One statement contains, "If, either, or" HELP!

Posted: Mon Oct 11, 2010 6:59 pm
by kilgoretrout103
"-J" means "not justified."

Re: WFT? One statement contains, "If, either, or" HELP!

Posted: Mon Oct 11, 2010 7:06 pm
by cubswin
youknowryan wrote:
kilgoretrout103 wrote:Ziggie is right.

Formal logic:

-J -> (I v L)

J = Bob's dismissal was justified
I = incompetent
L = late

-J = justified or NOT justified?
kilgoretrout103 wrote:"-J" means "not justified."
I assume Kilgore rushed through this, since he correctly said that Ziggie was right. But the statement was "If Bob's dismissal was justified, then he was either incompetent or late." This making his symbolization (starting with ~J) incorrect. It should be

J --> I v L