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by whoisburbansky 2076 days ago
The way he phrases it is "What can we say about !A and !B," according to the article. The only time he talks about "If A implies B, does not A imply not B," is when describing close answers he got to his question. I don't think it's a trick question the way he asks it, and it also seems like the sort of thing you should be able to work out with concrete examples if you aren't sure.