A statement is “vacuously true” if it resembles a material conditional statement , where the antecedent. is known to be false.
A vacuous truth is a conditional or universal statement that is true because the antecedent cannot be satisfied. It is sometimes said that a statement is vacuously true because it does not really say anything.
“All cell phones in the room are turned off” is true when there are no cell phones in the room.