Complex Predicates again: Asymmetry as origin of light verb distribution

In many contemporary Ir. languages, complex predicates come in pairs, with one member functioning as active or transitive member (in Persian with kardan, zadan, etc.), the other one as its passive or intransitive counterpart (with sodan, xwordan, etc.). While many studies have looked at the matter from a theoretical perspective, studies of its historical development are rare. This paper thus proposes at possible origins and logics of the distribution of light verbs.