causativeanticausative

Causative-anticausative refers to a diathesis in some languages where a single verb has two related forms that encode opposite valency or participant structure. The causative form expresses that the subject causes an event to occur, typically introducing or increasing transitivity by adding an external causer or agent. The anti-causative (or anticausative) form marks that the event happens without an explicit external causer, often yielding an intransitive or patient-focused reading in which the subject undergoes a change of state or experiences the event.

In practice, languages realize this opposition in diverse ways. The causative may be built with morphological affixes, such as prefixes, suffixes, or stem changes, or it may arise through periphrastic constructions. The anti-causative is similarly variable, appearing as a distinct form, a reflexive or passive construction, or an intransitive reinterpretation of the base verb. In many systems, causatives increase verbal valency by adding an external participant, while anti-causatives reduce valency and foreground the affected undergoer rather than the causer.

Semantically, the causative is used when an agent intentionally brings about an event or state, whereas the anti-causative is used when the event occurs without an overt agent, often with a sense of spontaneity, inevitability, or the subject’s involvement as the undergoing participant. The two forms thus illustrate a cross-linguistic pattern of valency-changing diatheses and are closely related to, but distinct from, voice alternations such as active/passive or antipassive.

Causative-anticausative patterns are of interest in typology and historical linguistics, where they shed light on how languages encode agency, causation, and event structure.