• @[email protected]
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        210 months ago

        If B then A is the same as if X then Y is the same as if A then B. They are saying it’s the same as the OP. Changing the letters around doesn’t change the meaning since the letters are just placeholders.

        Now if you said If A then B AND If B then A as one it wouldn’t be the same because A and B would have to keep the same meaning.

      • @[email protected]
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        110 months ago

        I mean it is the definition of “if and only if”. And by commutativity we also know that A iff B is equal to B iff A

          • @[email protected]
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            110 months ago

            Yeah if vs iff can be confusing at first. Trying to understand it with normal grammar doesn’t work right. It’s a lot more helpful to grok the symbols and so the truth tables by hand to see how they fit together