Previous typological studies of impersonal pronouns show that to a certain degree, the generic/arbitrary readings of these syntactically projected arguments correspond to specific structures, case assignment patterns, and their compatibility with specific time references (e.g., Cinque 1988; Egerland 2003a,b; Fenger 2018; Šereikaitė 2022). However, almost all of these studies focus on the Indo-European language family, especially Germanic and Romance languages. Drawing data from implicit causees in three periphrastic causatives in Teochew, an understudied variety of Southern Min (Sinitic), I show that they have generic/arbitrary readings, and hence are analyzed as impersonal pronouns. However, even as the same thematic category, i.e., causee, these implicit arguments have different syntactic and semantic properties, corresponding to the long-standing observation that implicit arguments do not form a homogeneous category (see a more recent discussion in Akkuş 2021a). In addition, these implicit causees provide valuable typological insights to the discussion of impersonal pronouns. More specifically, I show that even when it is not syntactically projected, an implicit causee with a generic/arbitrary reading patterns with impersonal pronouns in terms of the compatibility between the choice of reading and temporal reference. In addition, syntactically projected implicit causees as impersonal pronouns can have a structure as large as DP, an observation never made before for null impersonal pronouns. Moreover, discussions of Case for impersonal pronouns might require finer review if languages without morphological cases are considered. Finally, an impersonal pronoun can be [-human], contrasting with the typical [+human] property argued in much previous literature. All of these demonstrate that more than one type of phonologically null impersonal pronouns can exist in a single language.
