Judgment Under Uncertainty Revisited: Probability vs Strength  of Inductive Support

Kahneman and Tversky famously identified various  "fallacies" of uncertain reasoning.  In this talk, I will take  another look at some of these "fallacies".  I will suggest that they  may not be as fallacious as they first appear.  They may stem from a  conflation of probability and strength of inductive support: two  closely-related but distinct concepts that arise in the context of  uncertain reasoning.  The talk will have a normative (philosophical)  component and an empirical (psychological) component.  I will argue  (a) that people DO tend to make judgments about strength of inductive  support in a way that would explain many of the results of  experiments by Kahneman, Tversky, and others, and (b) that these  patterns of judgment about strength of inductive support are  (normatively) rational.  In part (a), I will appeal not only to  speculative (philosophical) charitable reconstruction, but also to  some recent experiments of Osherson et al that were explicitly  designed to test people's judgments about strength of inductive  support against the normative standards I will discuss in part (b).