Seminar by Ralph Hertwig

Friday 23 October 2026, at 11:00 AM, Henri Gastaut meeting room, INT

Ralph Hertwig (Max Planck Institute for Human Development, Berlin) invited by Patrick Pintus

How experimental methods shaped views on human competence and rationality

Abstract: Within just 7 years, behavioral decision research in psychology underwent a dramatic change: In 1967, Peterson and Beach (1967) reviewed more than 160 experiments concerned with people’s statistical intuitions. Invoking the metaphor of the mind as an intuitive statistician, they concluded that “probability theory and statistics can be used as the basis for psychological models that integrate and account for human performance in a wide range of inferential tasks” (p. 29). Yet in a 1974 Science article, Tversky and Kahneman rejected this conclusion, arguing that “people rely on a limited number of heuristic principles which reduce the complex tasks of assessing probabilities and predicting values to simple judgmental operations” (p. 1124). With that, they introduced the heuristics-and-biases research program, which has profoundly altered how psychology, and the behavioral sciences more generally, view the mind’s competences and rationality. How was this radical transformation possible? We examine a previously neglected driver: The heuristics-and-biases program established an experimental protocol inbehavioral decision research that relied on described scenarios rather than learning and experience. We demonstrate this shift with an analysis of 604 experiments, which shows that the descriptive protocol has dominated post-1974 research. Specifically, we examine two lines of research addressed in the intuitive-statistician program (Bayesian reasoning and judgments of compound events) and two lines of research spurred by the heuristics-and-biases program (framing and anchoring and adjustment). We conclude that the focus on description at the expense of learning has profoundly shaped the influential view of the error-proneness of human cognition.

Ralph Hertwig is the Director of the Center of Adaptive Rationality (ARC) at the Max Planck Institute for Human Development in Berlin. Before joining the institute, Hertwig was a professor for cognitive and decision sciences and Dean at the University of Basel, Psychology Department. His research focused on how people make decisions and how good decisions can be fostered.