Equal is a logical function of an arbitrary number of arguments. Its value is False if there exists at least one pair of unequal elements. By this criterion it is true on sets with less than 2 elements. Equal[] -> True, Equal[x] -> True

Unequal evalutes to True only if there exists no equal pair

Unequal[] -> True

In both cases the "if there exists a pair" clause is false, the rest of the clause is not tested according to the rules fixed for AND by exiting with False at the first occurence of a "FALSE" argument.

Regards Roland