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I found this proof on a blog I read. Can you find what (if anything) is wrong with it?

Here's a link to the whole post: http://www.analphilosopher.com/posts/1068508260.shtml" [Broken]

Here's a link to the whole post: http://www.analphilosopher.com/posts/1068508260.shtml" [Broken]

1. A conditional statement is false if and only if its antecedent is true and its consequent is false.

2. Z = If Z is true, then Keith is God. (That is, let "Z" be the statement "If Z is true, then Keith is God.")

3. Z is a conditional statement.

Therefore,

4. If Z is true, then either (a) "Z is true" is true and "Keith is God" is true, (b) "Z is true" is false and "Keith is God" is true, or (c) "Z is true" is false and "Keith is God" is false (from 1, 2, and 3).

5. It is not the case that (if Z is true, then "Z is true" is false and "Keith is God" is true).

6. It is not the case that (if Z is true, then "Z is true" is false and "Keith is God" is false).

Therefore,

7. If Z is true, then "Z is true" is true and "Keith is God" is true (from 4, 5, and 6, Impl, Assoc, Com, Impl, DeM, DN, Com, Simp, Impl, DeM, DN, Com, Simp, Conj, DeM, DS, Impl).

Therefore,

8. If Z is true, then "Keith is God" is true (from 7, Impl, Dist, Com, Simp, Impl).

Therefore,

9. If Z is false, then "Z is true" is true and "Keith is God" is false (from 1, 2, and 3).

Therefore,

10. If Z is false, then "Z is true" is true (from 9, Impl, Dist, Simp, Impl).

Therefore,

11. If Z is false, then Z is true (from 10).

Therefore,

12. Z is true (from 11, Impl, DN, Taut).

Therefore,

13. "Keith is God" is true (from 8 and 12, MP).

Therefore,

14. Keith is God (from 13). Q.E.D.

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