 Clauses (2) and (3) allow the degenerate case that the list of universal quantifiers is empty \((n = 0)\). The resulting expressions \((\exists x\)/) and \((\vee\)/) are identified with the usual existential quantifier \((\exists x)\) and the usual disjunction \(\vee\), respectively. Similar stipulations are made about clauses (4) and (5).