Speaker: Athulya Aravind (MIT)
Title: Principles of presupposition in development
Time: Thursday March 8th, 12:30-2:00pm
Place: 32-D461
Abstract:
Natural language affords us the means to communicate not only new information, but also information that we are already taking for granted, our presuppositions. The proper characterization of presuppositions–the way they enter into the compositional semantics and the way they fit into the exchange of information in communicative situations–has been at the center of long-standing debate. One class of theories treat presuppositions as categorically imposing restrictions on the conversational common ground: presuppositions must signal information that is already mutually known by all participants. While principled and elegant, these theories are often thought to be empirically inadequate, as the common ground requirement is not always met in everyday conversation. A second class of theories, therefore, adopt weaker and less categorical approaches to the phenomenon that are nonetheless a better fit to the empirical facts.
This talk compares these two classes of approaches to presupposition in terms of their implications for language acquisition. I argue that children initially adopt a view of presuppositions as uniformly placing restrictions on the conversational common ground, even in situations where these requirements may be bent. More tellingly, I show that children initially lack the ability to use presuppositions in ways that violate the common ground requirement. The observed two-step developmental trajectory supports a common ground theory of presuppositions, according to which the “rule of thumb” is that presuppositions are already common knowledge, and informative uses involve strategic violations of this rule. In turn, the acquisition data vindicate some of the theoretical idealizations whose empirical validity is masked in part due to the pragmatic sophistication of adult language users.