Biconditional elimination

Biconditional elimination allows one to infer a conditional from a biconditional: if ( A ↔ B ) is true, then one may infer either direction of the biconditional, ( A → B ) and ( B → A ).

For example, if it's true that I'm breathing if and only if I'm alive, then it's true that if I'm breathing, I'm alive; likewise, it's true that if I'm alive, I'm breathing.

Formally:

( A ↔ B ) ∴ ( A → B )

also

( A ↔ B ) ∴ ( B → A )

ee also

*Logical biconditional
*If and only if


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