In order, finally, to show the systematic connection of all these di alectical assertions in a sophisticala doctrine of the soul, in a connection of pure reason, and hence to show its completeness, one notes that ap perception is carried through by all classes of categories, but only to ward those concepts of the understanding which in each class ground the unity of the remaining ones in a possible perception, consequently, subsistence, reality, unity (not plurality), and existence; yet reason rep resents them all here as conditions of the possibility of a thinking being, which are themselves unconditioned.