Title: Language, reasoning, and commonsense knowledge
Speaker: Noah Goodman (Stanford University)
Date: Tues 9-3-2013
Time: 4:00 PM
Location: Singleton Auditorium, MIT 46-3002
Host: Prof. Joshua B. Tenenbaum; Tim O’Donnell
Human reasoning is a beautiful puzzle: it is productive, extending to new situations without bound, and it is uncertain, dealing gracefully with noisy evidence and shades of belief. Reasoning is also a key window on cognition, providing some of our best evidence about the structures that underly everyday, commonsense thought. I will argue that the core representations that support reasoning can be understood as a ‘probabilistic language of thought’, and that reasoning is an approximation to probabilistic inference. I will illustrate this claim with examples of reasoning about games and property induction. However, I will suggest that the bridge between the probabilistic language of thought and empirical data is a firm understanding of natural language. I will sketch a model of natural language pragmatics and semantics, and describe experimental evidence from communication games and quantity implicature. I will then describe how we can extend this framework to encompass vague language, focussing on scalar adjectives (like “tall”). I will conclude by coming back to reasoning, explaining two puzzling patterns: the sorites paradox and the effect of additional premises when reasoning general-to-specific. Time permitting, I will discuss possible process-level implementations in a short coda.