Conditional Logic question

InfiniteHubris
Posts: 1
Joined: Sun Mar 03, 2013 2:38 am

Conditional Logic question

Postby InfiniteHubris » Sun Mar 03, 2013 2:43 am

with questions that have "And in the trigger"- I'm a bit confused about the validity of the contrapositives.

For example,

If both P and Q are selected, then R is selected.

P and Q-> R

The contrapositive being-

-R-> -P or –Q

However, since it’s P AND Q that are sufficient to cause R
Couldn’t you not have R (-R) and still have P? But not Q. Alternatively, have Q, but not P.

Any explanation would be saaahhweeetttt.

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CardozoLaw09
Posts: 1744
Joined: Sat Aug 28, 2010 1:58 pm

Re: Conditional Logic question

Postby CardozoLaw09 » Sun Mar 03, 2013 3:10 am

You can have one and not the other and you can also not have both.

So you can have ~P and have Q or the other way around; and you can also not have both of them.

peeonyou
Posts: 71
Joined: Fri Mar 01, 2013 10:58 pm

Re: Conditional Logic question

Postby peeonyou » Sun Mar 03, 2013 3:38 am

CardozoLaw09 wrote:You can have one and not the other and you can also not have both.

So you can have ~P and have Q or the other way around; and you can also not have both of them.

he's right.

to give an example:

if you drink and you drive -> you can get a DWI.

if you can't get a DWI -> you are either not drinking, not driving or not doing either one.




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