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 Th7:
  bound_in All(x,p) = x & the_scope_of All(x,p) = p
proof
  All(x,p) is universal;
  then All(x,p) = All(bound_in All(x,p), the_scope_of All(x,p)) by Th6;
  hence thesis by Th5;
end;
