Relation Has-Some

Instance-Of: Binary-Relation, Relation, Set
Arity: 2
Binary relation R HAS-SOME values on domain instance i if there exists at least one value v such that R(i,v) holds.

When used in the definition of a class where ?i is the instance variable, (HAS-SOME ?i R) means that the slot R must always have a value when applied to instance of that class.

Equivalence Axioms for Has-Some:

(<=> (Has-Some ?Instance ?Binary-Relation)
     (Has-At-Least ?Instance ?Binary-Relation 1))