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1) if B then A 2) if not B, then not A. Which implies if A then B.

1) if B then A

2) if not B, then not A. Which implies if A then B.

... but then he went on to say "How can an equivalent argument have explanatory power?" which seemed, to me, to assume that "if B then A" and "if A then B" are equivalent (which they are not).

I read that statement as implying that argument A is equivalent to argument B. (Not (1) and (2), which are statements about arguments A and B)

And, if A implies B and B implies A, then it seems to me that A and B have to be equivalent to each other.

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## Comments (102)

Best*0 points [-]... but then he went on to say "How can an equivalent argument have explanatory power?" which seemed, to me, to assume that "if B then A" and "if A then B" are equivalent (which they are not).

I read that statement as implying that argument A is equivalent to argument B. (Not (1) and (2), which are statements

aboutarguments A and B)And, if A implies B

andB implies A, then it seems to me that A and B have to be equivalent to each other.