Namely, I argue against the widely held assumption that (thematic) wa has a uniform function, say topic-marker or ground-marker, and propose that wa marks a topic only when it is associated with certain grammatical functions (GF's), such as direct object, while it merely indicates groundhood (givenness) when it is associated others, including subject.
i propose that what has been traditionally called thematic wa is an amalgam of 'topic-marking wa' and 'ground-marking wa'.