Despite displaying identical exponents (a reflexive clitic, imperfective tenses and agreement between the verb and the preverbal definite DP theme), change-of-state predicates in generic/middle contexts (inchoative middles, henceforth), can in fact have two different underlying representations: (i) a generic inchoative and (ii) a generic se-passive, this being the only one projecting a Voice head passivized by the reflexive clitic, which denotes an implicit generic external argument. Spanish allows the insertion of an affected applicative head in inchoative configurations ( Cuervo 2003), which introduces an unselected dative argument interpreted either as an unintentional causer of the event if merged above the verbalizing head, or as affectee if merged below it. Crucially, this paper shows that the generic passive configuration disallows the applicative’s unintentional causer interpretation, since the position above vP is already filled by Voice; therefore, the only available merging position for the applicative is below vP. However, the unintentional causer interpretation is possible in generic inchoative constructions, which lack a VoiceP. The data and analysis presented here support Wood and Marantz’s ( 2017) proposal of a single argument-introducing head whose category and interpretation vary in terms of the syntactic context it is merged in. Finally, this study stresses the need to establish a more detailed classification of Spanish se-constructions as a whole and middles in particular with respect to their interaction with applied arguments.