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> A -> B does not imply !B -> !A A -> B does imply !B -> !A. The error in reasoning here seems to be that attitude towards a website is assumed to be a binary
by tr352 9y ago
> A -> B does not imply !B -> !A
A -> B does imply !B -> !A. The error in reasoning here seems to be that attitude towards a website is assumed to be a binary "like/not like" variable, while in reality one can also neither like nor dislike something.
- snovv_crash 9y agoNo it doesn't. Just because you tell me you don't like to get shot doesn't mean you are ok with being stabbed.
- matt4077 9y agoWhile it pains me to admit: They're actually right, and I was wrong above.
- tr352 9y agoYes it does. In fact, in classical logic, A->B is equivalent to !B->!A. See https://en.m.wikipedia.org/wiki/Contraposition https://en.m.wikipedia.org/wiki/Contraposition
- spookyuser 9y agoExactly. A consequence of this being true is the Raven Paradox [1], seemingly the OP has solved the classic riddle in a HN thread. [1] https://en.wikipedia.org/wiki/Raven_paradox https://en.wikipedia.org/wiki/Raven_paradox