Professor Gendler begins with a demonstration of sampling bias and a discussion of the problems it raises for empirical psychology. The lecture then returns to divisions of the soul, focusing on examples from contemporary research. The first are dual-processing accounts of cognition, which are introduced along with a discussion of the Wason selection task and belief biases. Next, the influential research of Kahneman and Tversky on heuristics and biases is introduced alongside the famous Asian disease experiment. Finally, Professor Gendler introduces her own notion of alief and offers several examples that distinguish it from belief. Complete course materials are available at the Open Yale Courses website: http://oyc.yale.edu This course was recorded in Spring 2011.