It is often a tautology - a statement which is true bit adds nothing to anyone's knowledge. A recent example is the fatuous remark by the British Prime Minister "Brexit is Brexit".
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The empty set is open because the statement: "if x in A, some neighborhood of x is a subset of A" is true! If A is empty, the hypothesis: "if x in A" is false and so the statement is vacuously true.
I believe you are talking about subsets. The empty set (set with no elements) is a subset of any set, including of the empty set. ("If an object is an element of set A, then it is also an element of set B." Since no element is an element of set A, the statement is vacuously true.)
In computing, this is an AND statement.
No, it is not a true statement. It is a false statement.
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