**Defined in theory: Kif-relations****Source code: kif-relations.lisp**

**Documentation:**If $tau$ denotes a function with a value for the objects denoted by $tau_1$,..., $tau_k$, then the term {tt (value $tau$ $tau_1$ ... $tau_k$)} denotes the value of applying that function to the objects denoted by $tau_1$,...,$tau_k$. Otherwise, the value is undefined.

(Undefined (Arity Value)) (= (Value ?F @Args) (If (And (Function ?F) (Member ?List ?F) (= (Butlast ?List) (Listof @Args))) (Last ?List)))