Some Oralists do not go so far as to claim that the Homeric epics actually are products of an oral epic tradition: many limit themselves to claiming that the Homeric epics merely draw on earlier oral epic. For much of the mid-20th century much of the resistance to Oral Theory came from scholars who could not see how to preserve Homer as the great original poet: they could not see how there was any room for artistry and creativity in a formulaic system where set-piece episodes (Walter Arend's "type scenes") were as formulaic as Parry's metrical epithet-noun combinations. Some scholars divided Oralists into "hard Parryists", who believed that all aspects of Homeric epic were predetermined by formulaic systems, and "soft Parryists", who believed that Homer had the system at his command rather than the other way round. More recently, books such as Nagy's influential 1979 book about epic heroes, "The Best of the Achaeans", and Egbert Bakker's 1997 linguistic study "Poetry as Speech", work on the principle that the radical cross-fertilisation and resonances between different traditions, genres, plot lines, episodes, and type scenes, are actually the driving force behind much of the artistic innovation in Homeric epic.