Daniel Kahneman, Nobel laureate, 90
Daniel Kahneman, an Israeli-American psychologist and best-selling author whose Nobel Prize-winning research upended economics — as well as fields ranging from sports to public health — by demonstrating the extent to which people abandon logic and leap to conclusions, died Wednesday. He was 90.
His death was confirmed by his stepdaughter Deborah Treisman, the fiction editor for the New Yorker. She did not say where or how he died.
Dr. Kahneman’s research was best known for debunking the notion of “homo economicus,” the “economic man” who since the epoch of Adam Smith was considered a rational being who acts out of self-interest. Instead, Dr. Kahneman found, people rely on intellectual shortcuts that often lead to wrongheaded decisions that go against their own best interest.
These misguided decisions occur because humans “are much too influenced by recent events,” Dr. Kahneman once said. “They are much too quick to jump to conclusions under some conditions and, under other conditions, they are much too slow to change.”
Dr. Kahneman was affiliated with Princeton University when he shared the 2002 Nobel Memorial Prize in Economic Sciences “for having integrated insights from psychological research into economic science, especially concerning human judgment and decision-making under uncertainty.” His co-recipient, Vernon L. Smith, then of George Mason University in Virginia, pioneered the use of laboratory experiments in economics.
Dr. Kahneman took a dim view of people’s ability to think their way through a problem. “Many people are overconfident, prone to place too much faith in their intuitions,” he wrote in his popular 2011 book “Thinking, Fast and Slow.” “They apparently find cognitive effort at least mildly unpleasant and avoid it as much as possible.”
Dr. Kahneman spent much of his career working alongside psychologist Amos Tversky, who he said deserved much of the credit for their prizewinning work. But Tversky died in 1996, and the Nobel is never awarded posthumously.
Both men were atheist grandsons of Lithuanian rabbis, and both had studied and lectured at Hebrew University. Their three-decade friendship and close collaboration, chronicled in Michael Lewis’s 2016 book “The Undoing Project,” was a study in opposites.
According to Lewis, Tversky was the life of the party; Dr. Kahneman never even went. Tversky had a mechanical pencil on his desk and nothing else; Dr. Kahneman’s office was full of books and articles he never finished. Still, Dr. Kahneman said, at times it was as if “we were sharing a mind.” They worked so closely together that they tossed a coin to decide whose name would go first on an article or a book.
Their research helped establish the field of behavioral economics, which applies psychological insights to the study of economic decision-making, but also had a far-reaching effect outside the academy. It was credited with changing the way baseball scouts evaluate prospects, governments make public policy, and doctors arrive at medical diagnoses.
Dr. Kahneman and Tversky did experiments that demonstrated various cognitive biases. They showed, for instance, that many more people were willing to make a 20-minute trip to save $5 on the price of a $15 calculator than to make the same trip to save the same amount of money, $5, on a $125 calculator — an example of what is known as the framing effect.
Daniel Kahneman was born in Tel Aviv on March 5, 1934, while his mother was visiting relatives in what was then the British mandate of Palestine. The Kahnemans made their home in France, and young Daniel was raised in Paris, where his mother was a homemaker and his father was the chief of research for a cosmetics firm.
At 15, he took a vocational test that said he had the makings of a psychologist. He graduated from Hebrew University in 1954 with a bachelor’s degree in psychology and mathematics. In 1961, Dr. Kahneman received a doctorate in psychology from the University of California at Berkeley.
Dr. Kahneman received the Presidential Medal of Freedom, the nation’s highest civilian honor, from President Barack Obama in 2013.