LingLang Lunch (10/2/2013): Josh Hartshorne (MIT)

Syntax, Semantics, World Knowledge, and Reference

Consider these examples from Winograd (1972):

(1) The city council denied the protesters a permit because they feared violence.
(2) The city council denied the protesters a permit because they advocated violence.

Most people reliably attribute different interpretations to they in (1-2), though in principle in each case the pronoun could refer to the city council, the protesters, or someone else. Levesque (2012) has argued that solving such sentences draws on such a wide range of cognitive abilities that it is an even stronger test of human intelligence than the original Turing Test.

Psycholinguists, too, have been interested in ambiguous pronouns. In 1974, Garvey and Caramazza demonstrated that people have strong expectations about the meanings of pronouns even without having heard the potentially critical end of the sentence:

(3) The city council denied the protesters a permit because they…
(4) Sally frightened Mary because she…
(5) Alfred liked Bernard because he…

These intuitions can be modified by such a bewildering range of contextual manipulations that here, too, many commentators resorted to attributing pronoun reference to inference over ill-specified concepts such as “event structure” (Pickering & Majid, 2007) or “salience” (Song & Fisher, 2004).

In this talk, while I concede that pronoun reference is very difficult and that, in the limit, it requires a broad swath of cognition, we nonetheless are already in a position to say quite a lot about it. Much of the complexity of the phenomena reduce to the interactions of a small number of abstract structures in semantics and discourse. I demonstrate this with a combination of experiments and computational modeling.