% Universals over infinite domains are proven or refuted % symbolically, never enumerated. % The specification's true example: every natural is at least zero. Query expression: [ForAll variable: X quantifier: [Natural value: X] body: [GreaterEqual left: X right: 0]] % The specification's false example: not every integer is. Query expression: [ForAll variable: X quantifier: [Integer value: X] body: [GreaterEqual left: X right: 0]] % Subtype inclusion, decided symbolically: every integer is a % rational, literally. Query expression: [ForAll variable: X quantifier: [Integer value: X] body: [Rational value: X]] % The algebra of Plus: adding zero is the identity, over all % integers, stated flat as membership. Query expression: [ForAll variable: X quantifier: [Integer value: X] body: [Plus left: X right: 0 result: X]] % Universals over finite quantifiers just run. Query expression: [ForAll variable: X quantifier: [Between value: X lower: 1 upper: 5] body: [GreaterThan left: X right: 0]] % Existence, over a finite quantifier. Query expression: [Exists variable: X quantifier: [Between value: X lower: 1 upper: 10] body: [Times left: X right: X result: 49]]