 Its names are usually derived from Proto-Austronesian "*qaNiCu" ("ghost", "spirit [of the dead]"), which also apply to other non-human nature spirits.The "free soul" is also referred to in names that literally mean "twin" or "double", from Proto-Austronesian "*duSa" ("two").A virtuous person is said to be one whose souls are in harmony with each other, while an evil person is one whose souls are in conflict.