The Legacy of Daniel Kahneman:

s joint papers from the 1970s and 1980s have inspired many, including myself.These articles magically turned statistical thinking-previously a niche interest-into a major research focus.Kahneman and Tversky revived the concept of heuristics, which had largely been forgotten at the time, and played a pivotal role in bringing psychology to the attention of economics and other social sciences.I was also deeply influenced by Tversky's seminal work on the foundations of measurement, which inspired my first book on modeling (Gigerenzer 1981).In their joint work, known as the heuristics-and-biases program, Kahneman and Tversky argued that human judgment systematically deviates from the norms of probability and logic, resulting in predictable cognitive biases.These biases were attributed to heuristics-mental shortcuts-which led to a broader narrative in behavioral economics and psychology that emphasized human fallibility in decision-making.The heuristics-and-biases program sparked intense debate on the nature of human rationality.This debate placed me in direct opposition to Kahneman and Tversky, with Kahneman referring to me in Thinking, Fast and Slow (Kahneman 2011, 449) as "our most persistent critic".At stake was more than simply an academic disagreement-it was a fundamental clash of worldviews on rationality, intelligence, the standards for sound judgment, and their implications for policy-making.In this article, I will focus on Kahneman's legacy: the contributions made and the opportunities missed.After discussing these, I reflect on the challenges we faced in our exchanges, both as fellow scientists and fellow human beings.It is of course impossible to discuss Kahneman without referring to Tversky as well, given that much of Kahneman's early work was written with him.At the same time, although Kahneman and Tversky are often spoken of as a unit, they were markedly different, both personally and scientifically.This contrast was part of their success.For more than a dozen years, they formed a highly influential partnership.However, their differing personalities also led to the eventual end of their GIGERENZER / THE LEGACY