On 4/4/06, Jonathan Lang <[EMAIL PROTECTED]> wrote: > OK, then; what would be the specification for a _single_ set that > contains everything that doesn't intersect with a corresponding all() > Junction (the sort of thing that I'd use if I wanted to find the > largest subset of A that doesn't intersect with B)?

Can't do it. Here's a proof. Suppose you could find a _single_ set that contains everything that doesn't intersect some other set (the complement). Let S be the complement of the empty set. S is not an element of the empty set, so it must be a member of S, which is impossible. Finding the complement of a set assuming some other set is not hard though, simply by using the set difference operator. Luke