Thematic roles

It is often convenient to identify arguments of (Fregean) predicates in terms of thematic roles such as the following: Agents are arguments that bring about a state of affairs. The line between agents, on the one hand, and instruments or causes, on the other, can be fuzzy, but agents are (or are perceived to be) conscious or sentient, in a way that instruments or causes aren't. Some examples are given in (1)-(3).

(1) a. Agent:   The lions devoured the wildebeest.
b.   The boys caught some fish.
c.   My mother wrote me a letter.
(2) a. Instrument:   This key opens the door to the main office.
b.   They must have used indelible ink.
(3) a. Cause:   Hurricane-force winds demolished much of the town.
b.   An epidemic killed off all of the tomatoes.
c.   An economic downturn put thousands of workers out of work.

Experiencers are arguments that undergo a sensory, cognitive, or emotional experience.

(4) a. Experiencer:   The rhesus monkey had never seen snow before.
b.   Many people fear snakes.
c.   Their resourcefulness struck her as admirable.

Recipients are arguments that receive something (whether good or bad) in a situation.

(5) a. Recipient:   They gave the workers a raise.
b.   He spared me his usual sob story.
c.   I paid my landlord the rent.

Goals are the endpoints of paths.

(6) a. Goal:   I'd like to send this package to France.
b.   They invited the Holtenbrooks to their house for dinner.
c.   Lucky raced across the lawn to the edge of the forest.
(7) a. Path:   Lucky raced across the lawn to the edge of the forest.
b.   We drove the scenic route.

Measure or amount arguments express extension along some dimension (length, duration, cost, and so on).

(8) a. Measure:   They rowed for three days.
b.   The book costs ten dollars.

Finally, the thematic role of theme is something of a catch-all. According to one definition, 'theme' refers to an argument undergoing motion of some sort, including motion in a metaphorical sense, such as a change of state. As is usual in the syntactic literature, we will also use the term for arguments that are most 'affected' in a situation or for the content of an experience.

(9) a. Theme:   The lions devoured the wildebeest.
b.   This key opens the door to the main office.
c.   Hurricane-force winds demolished much of the town.
d.   They gave the workers a raise.
e.   I'd like to send this package to France.
f.   Many people fear snakes.