Nobel-winning behavioral economist Daniel Kahneman, who upended his field, dies at 90
Israeli-American psychologist and Holocaust survivor proved the irrationality of decision-making, arguing people’s mental biases often lead them to act against their own interests
Daniel Kahneman, an Israeli-American psychologist who broke ground in the field of behavioral economics and upended the common assumption in economics that human beings are rational decision-makers, died on March 27 at the age of 90.
The Israeli-born author won the 2002 Nobel Prize in Economic Sciences for his research integrating psychology and economics, which challenged the notion that people act rationally. Instead, he argued, people’s mental biases often lead them to make decisions that run counter to their own interests.
Kahneman’s death was confirmed by his partner, Barbara Tversky and step-daughter, Deborah Weisman, an editor at the New Yorker. He lived in Manhattan at the time of his death.
Born in Israel while his mother was visiting relatives, Kahneman was raised in Paris on the brink of World War II, and spent his early life under the Vichy regime and Nazi occupation. When Nazis began to arrest French Jews en masse, he and his family found refuge hiding in a chicken coop in Cagnes-sur-Mer.
Kahneman’s father, a diabetic, was unable to secure medication for his condition while in hiding, and died just six weeks before the Allies liberated France.
After moving with his mother and sister to Mandatory Palestine following the war, Kahneman spent his adolescence in Jerusalem in the country’s first decade of existence.
It was in high school that Kahneman became acquainted with famed biochemist and thinker Yeshayahu Leibowitz, whom he recalled had a major influence on his intellectual development and was “bigger than life.”
Leibowitz was both the father of his childhood best friend and his high school chemistry teacher. Kahneman continued to study under him at the Hebrew University, where he received his bachelor’s degree in psychology and mathematics.
After receiving his PhD in psychology from the University of California at Berkeley, Kahneman returned to Israel to lecture at the Hebrew University, where he met the psychologist Amos Tversky.
The two scholars quickly became close friends and collaborated on research which integrated cognitive psychology with economics. Their joint work earned Kahneman a Nobel Prize, but only after Tversky’s death in 1996.
When he and Tversky both lived and taught in Jerusalem, Kahneman recalled spending hours on end with his colleague writing a relatively brief paper, “Judgement under Uncertainty,” a prelude to the next few decades of their research.
“Amos and I wrote every word together, and we spent a lot of time on every sentence. And we really tried not to have a superfluous word. The prose doesn’t flow because every word was chosen. We spent almost a year writing those five pages. We did little else,” he said.
In 2013, former US president Barack Obama awarded Kahneman with the Presidential Medal of Freedom, the country’s highest civilian honor. Obama lauded Kahneman at the ceremony as a scholar of psychology who “basically invented the study of human decision-making.”
The renowned psychologist was not shy to speak his mind on political developments in Israel. He signed his name on letters against government plans to politicize the National Library and more recently, partook in a written plea to international organizations urging action to return the hostages held by Hamas.
In the last few years of his life, Kahneman took a strong public stance against the Israeli government’s efforts — now on pause — to overhaul the judiciary. In an interview with Israel’s Channel 12 last year, he said that the government’s proposed changes, if realized, would signal “the end of the country” as he knew it.
Kahneman predicted that the moment “the executive authority will supersede the judicial authority… that’s the end of democracy. There is no doubt.”
Kahneman married twice, first to Irah Kahn, a marriage that ended in divorce. Next he married Anne Treisman in 1978, a fellow psychologist at Princeton University. When Kahneman moved to join Princeton in 1993, his friendship with Tversky, who lectured at Stanford at the time, fizzled out.
Some time after Treisman’s death in 2018, Kahneman began a relationship with Tversky’s widow, Barbara Tversky. The two lived together for four years before Kahneman’s death.
Kahneman is survived by his two children Michael Kahneman and Lenore Shoham, step-children Jessica, Daniel, Stephen, and Deborah Treisman and seven grandchildren.
