• Casey_Masterpiece@lemmy.world
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        10 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.

        • Rhynoplaz@lemmy.world
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          10 months ago

          But they switched the order in only the first half of the statement. I don’t know if everyone commenting caught that.

          Is “If B then A” equal to “B if and only if A”?

          This IS different from the original question.

      • Thoth19@lemmy.world
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        10 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