 reserve R for 1-sorted;
 reserve X,Y for Subset of R;
 reserve R for finite 1-sorted;
 reserve X,Y for Subset of R;
 reserve R for finite Approximation_Space;
 reserve X,Y,Z,W for Subset of R;

theorem :: Proposition 2 e)
  Z misses W implies
    kappa (Y \/ Z, W) <= kappa (Y, W) <= kappa (Y \ Z,W) by Test1,Test2;
