Can someone please respond to this? I have the same question.
Mehranon September 20, 2018
@Eleazar @blconley6 because that is the rule. You seem to be confusing yourself with this example.
Notice you even state "it can't be both" which implies "not both" as opposed to "either/or."
However, if you actually encountered your example on the LSAT, it would be diagrammed as follows:
not R ==> S not S ==> R
And in this example, it is possible for it to be both sunny and raining (S and R can exist together because they are the necessary conditions which means their existence tells us nothing else), which actually can happen (Have you ever visited Paris in the summer? Or any humid climate for that matter).
But I would also like to point out that your example is not logically correct. Just because it is not sunny, doesn't necessarily mean it is raining. It could be night time or it could even be snowing.
The best example for "either/or" is a 24-hour store with only two employees. If one is not there, the other must be but there is nothing stopping them from being present together.
Try not to overthink these rules. Memorize them and apply them.
Hope that helps! Please let us know if you have any other questions.
