On the homomorphisms between Parabolic Verma modules over Kac-Moody Algebras.
We consider a more general parabolic category over symmetrizable Kac-Moody algebras. We introduce a Ringel dual between finite truncations of blocks of the parabolic category and a reductive rule of hom-spaces between parabolic Verma modules which yield some applications on the homomorphisms between parabolic Verma modules.