reserve A for QC-alphabet;
reserve sq for FinSequence,
  x,y,z for bound_QC-variable of A,
  p,q,p1,p2,q1 for Element of QC-WFF(A);

theorem
  All(x,y,p) is universal & bound_in All(x,y,p) = x & the_scope_of All(x
  ,y,p) = All(y,p) by Th7;
