What four word phrase will let you know that a statement is truly biconditional?

Definition: A biconditional statement is defined to be true whenever both parts have the same truth value. The biconditional operator is denoted by a double-headed arrow . The biconditional p <-> q represents "p if and only if q," where p is a hypothesis and q is a conclusion.
Biconditional Statements - Math Goodies
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