I present to you my new theorem as follows:
If 1 == 3 then 3 == 3
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This statement is 100% logically coherent internally. But it also doesn't matter because we know that 1 does not equal 3 so this proof is completely pointless. I could also say 3 == 5 and it would still be logically sound but completely useless information.
For a laymen, I don't follow this.
Are you proving for some arbitrary definition of == that isn't what we commonly consider the definition? How is it logically coherent? You mean only in the sense that you say it is and you haven't provided any rules to disprove it?