反证法是错误的
1 分•作者: slack3r•7 个月前
反证法是错误的。存在真、假和不可判定三种情况。
让我来解释一下它是如何运作的。
p => q 并不一定意味着 ¬q => ¬p。这里有三种情况。如果 ¬q 为真，那么 p 也可能不可判定。
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Proof by contrapositive is wrong. There is a true, false and undecidable case also.<p>Let me explain how it works.<p>p. =>. q. does not necessarily imply not q ==> not p. There are three cases here. If not q is true, then p can also be undecidable.