This paper argues that constructions with subject-experiencer psychological verbs are adjectival passives, contra the received view that constructions are verbal passives across the board. We put forth a battery of morphological, syntactic and semantic tests to support our claim. The divide, we argue, is based on the individual-level/stage-level distinction, rather than on the lexical category of the participle. We provide a theoretical, aspect-based account that generates the distribution of ser and estar in verbal and adjectival participles and paves the way for a comprehensive analysis of the ser and estar distribution across other constructions where the alternation is attested, such as underived adjectives and prepositions. [ABSTRACT FROM AUTHOR]