If I'm understanding correctly, I think you've made a mistake in your formal logic above—you equated "If B, then A" with "If A, then B" which is not at all the same.

The search for a double crux encourages each side to adopt the causal model of the other (or, in other words, to search through the other's causal models until they find one they can agree is true). I believe "If B, then A," which is meaningfully different from your belief "If ¬B then ¬A." If each of us comes around to saying, "Yeah, I buy your similar-but-different causal model, too," then we've converged in an often-significant way, and have almost always CLARIFIED the underlying belief structure.

Comment author:CCC
02 December 2016 07:56:32AM
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If I'm understanding correctly, I think you've made a mistake in your formal logic above—you equated "If B, then A" with "If A, then B" which is not at all the same.

No, he only inferred "If A, then B" from "If not B, then not A" which is a valid inference.

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).

## Comments (104)

Best*0 points [-]If I'm understanding correctly, I think you've made a mistake in your formal logic above—you equated "If B, then A" with "If A, then B" which is not at all the same.

The search for a double crux encourages each side to

adoptthe causal model of the other (or, in other words, to search through the other's causal models until they find one they can agree is true). I believe "If B, then A," which ismeaningfully differentfrom your belief "If ¬B then ¬A." If each of us comes around to saying, "Yeah, I buy your similar-but-different causal model, too," then we've converged in an often-significant way, and have almostalwaysCLARIFIED the underlying belief structure.No, he only inferred "If A, then B" from "If not B, then not A" which is a valid inference.

*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.