Agent (grammar)

In linguistics, a grammatical agent is the thematic relation of the cause or initiator to an event. The agent is a semantic concept distinct from the subject of a sentence as well as from the topic. While the subject is determined syntactically, primarily through word order, the agent is determined through its relationship to the action expressed by the verb.

Etymology

The word agent comes from the present participle agens, agentis ("the one doing") of the Latin verb agere, meaning "to do" or "to make."

Definition and Theory

Typically, the situation is denoted by a sentence, the action by a verb in the sentence, and the agent by a noun phrase. For example, in the sentence "Jack kicked the ball," Jack is the agent and the ball is the patient (the entity undergoing the action). In certain languages, the agent is declined or otherwise marked to indicate its grammatical role. Modern English does not mark the agentive grammatical role of a noun in a sentence, though certain nouns have a permanent trait of agency (e.g., runner, kicker). Notably, an agent noun is not necessarily an agent of a sentence: in "Jack kicked the runner," runner is the patient, not the agent.

Proto-Agent Theory

The linguist David Dowty proposed that typical qualities of a grammatical agent include having volition, being sentient or perceiving, causing a change of state, or moving. He defined a Proto-Agent and suggested that the nominal with the most Proto-Agent features and the fewest Proto-Patient features tends to be treated as the agent in a sentence. This approach addresses difficulties semanticists face in determining the number and quality of thematic roles. For example, in "His energy surprised everyone," His energy is the agent, even though it lacks typical agent-like qualities such as perception, movement, or volition.

Agent vs. Subject

The grammatical agent is often confused with the subject, but the two notions are distinct:

• The agent is based on its relationship to the action or event expressed by the verb (e.g., "he who kicked the ball").
• The subject is based on a more formal syntactic title using the theory of information flow.

In the active sentence "The boy kicked the ball," the boy is both the agent and the subject. However, in the passive voice — "The ball was kicked by the boy" — the ball is the grammatical subject, but the boy remains the agent. Many sentences in English and other Indo-European languages have the agent as subject.

Reciprocal Events

The use of some transitive verbs denoting strictly reciprocal events may involve a conflation of agent and subject. In the sentence "John met Sylvia," for example, though both John and Sylvia would equally meet Dowty's definition of a Proto-Agent, the co-agent Sylvia is downgraded to patient because it is the direct object of the sentence.

Examples

See Also

• Active–stative language
• English passive voice
• Passive voice
• Patient (grammar)
• Thematic relation
• Agent noun