A thematic role or semantic role is a way in which an object can relate to an event.
Some examples of thematic roles are:
- “agent”: who is willfully causing this event?
- “benefactor”: who benefits from this event?
- “patient”: who or what is affected/changed by this event?
Syntactic and thematic roles
Thematic roles exist in contrast to syntactic roles, like “subject” or “direct object”: these describe a way in which something participates in a verb at the syntax level.
In Toaq, syntactic roles are the ones already represented by the “blanks” in verb definitions:
choıdea: ___ stabs ___.
Whereas thematic roles are represented using verbs that relate an event to an object, generally used as prepositions ( ):
nhuq: ___ happens for ___'s benefit.
In the two sentences below, the syntactic subject and object are exchanged, but the thematic roles stay the same: Brutus, the agent, is causing change, while Caesar, the patient, suffers this change.
|Sentence||Syntactic roles||Thematic roles|
|(1) Choıdea mí Butusu mí Kaısa da.
Brutus stabs Caesar.
|(2) Bọchoıdea mí Kaısa mí Butusu da.
Caesar is-stabbed-by Brutus.
Note that the assignment of Agent and Patient roles to Brutus and Caesar happens “automatically” according to the semantics of choıdea. To stab is for an agent to stab a patient.
We can further dress the event up with a “benefactor” using a preposition:
(3) Choıdea mí Butusu mí Kaısa nhûq mí Loqgınu da.
(4) Bọchoıdea mí Kaısa mí Butusu nhûq mí Loqgınu da.
We say that the stabbing-event, or the being-stabbed-event, “happens for” Longinus's sake.
In Toaq deep syntax
(TODO: mention Spec𝑣P thematic role assignment vs. Spec/CompVP syntactic roles)
Table of thematic role words
Each of these has a definition like: “___ is an event with ___ as its (Role).”. The first column lists “transparent” forms, or one that are built from some representative root (like lıe ‘to experience’ for Experiencer, etc.). The second column is a made-up root that has the same meaning, but offers the convenience of being shorter or more elegant than its “transparent” counterpart – note that the word forms with an outgoing link (↗) are unofficial.
“Agent” and “patient” roles are usually baked into a transitive verb, so translating toıcha and techa can be a bit tricky or ambiguous.