Function SECOND-ITEM

returns the second item in the specified list. If the length of the list is 0 or 1, this function is undefined. This is different from Lisp's SECOND function, which returns NIL, which means both false and null list.
Arity: 2
Axioms:
(=> (Second-Item ?List ?Result)
    (And (List ?List)
         (Not (Null (Rest ?List)))
         (= ?Result (First (Rest ?List)))))