EDB — 252

[252]Prerequisites:[23T]↺↻,[026]↺↻,[1Y0]↺↻,[00S]↺↻. Let \(A\) be a non-empty set; we define \(B\) as the set that contains all the elements that are in all the elements of \(A\). Write a well-formed formula that defines \(B\), prove that \(B\) is indeed a set, and show that it is unique; for symmetry with the axiom [026]↺↻ we will indicate it with

It is related to the usual notation by the relation