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When does Exclusive Or, ⊕, automatically become Inclusive Or?

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Is X⊕ ¬X ≡ X ∨ ¬X ?

Anyways, without doing all the algebra and operations at the link below, how can I determine or see - by inspection - whether an Exclusive Or (⊕) can be simplified to an Inclusive Or? To wit, when does ⊕ imply Inclusive Or?

Now this is odd, yet an insightful lesson. I began this by saying that "Either... or..." is an exclusive-or; and yet, we simplified the proposition to the exact same one, but using an inclusive-or. Upon reflection, this makes perfect sense: we can use an inclusive-or, because we can't have A and ¬ A both be true. So we could still use the inclusive-or but have the whole proposition still function like an exclusive-or.

I am dodging algebra, as I am assuming that the poster (his name is poop man in the quote above) intuited that he can simplify the ⊕ in

(A ∧ ¬ B) ⊕ (¬ A ∧ C)

to an inclusive Or.

To wit, poop man started from intuition, then worked on the algebra. I'm assuming that he didn't dive head first into all that algebra, without any inkling or intuition whether he can simplify ⊕ into an inclusive-or.

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Note that X Xor not X = 1. (1 comment)

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Your equivalence is rather silly since both sides are constants. More completely:

A and ¬A = 0
A nand ¬A = 1
A or ¬A = 1
A nor ¬A = 0
A xor ¬A = 1

You can just as well ask when XOR becomes NAND, or when AND becomes NOR, since they have the same values in the cases above. Or since

2 + 2 = 4
2 * 2 = 4

when does addition become multiplication?

Finding an instance where the result of two different operations happens to result in the same value doesn't mean much at all.

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