1. Either if Ann plays her ukulele, then Ben will dance; or if Carl plays his ukulele, then Doris will dance.
2. If Doris dances, then Ernie and Frank will laugh.
3. Ann will not play her ukulele.
4. Therefore, Ernie and Frank will laugh.
1. (A > B) v (C > D)
2. D > (E & F)
4. C > D / E & F
5. C > D (D.S. 1, 3)
6. E & F (M.P. 2, 5)
Since E & F is the conclusion, the argument is valid, according to the Disjunctive Syllogism and Modus Ponens rules.
The above was to prove to myself that I understand logical proofs, seeing as how Logic and I are touch-and-go as of late. If I don't pass this class I will cry large tears of torment. Not just because of losing the ability to graduate, but because I know I can pass this thing if I just apply myself and stop horsing around.
To that end, next week I'm taking a break from Facebook, among a few other computer-related things. It's a time-killer and often I spend a long time on it doing nothing. I would take a break from the Internet altogether, except that my Logic class is...online. Doy.
Obviously this blog will still get updated every evening. But I need to pull myself out of the muck of low grades and figure this stuff out. So there.