“How did the world’s leading authority on decision-making [Daniel Kahneman] make the ultimate decision? How closely did he follow his own precepts on how to make good choices? How does his decision fit into the growing debate over the downsides of extreme longevity? How much control do we, and should we, have over our own death?
Before the groundbreaking research that Kahneman had conducted, much of it with Barbara Tversky’s late husband, Amos Tversky, economists had long assumed that human beings are rational. By that, they meant that people’s beliefs are internally consistent, they make decisions based on all the relevant information and their preferences don’t change.
[..] In short, he made the case that people are neither rational nor irrational; they are, simply, human.
Kahneman often said that decades of studying the human mind had taught him how to recognize— but not how to avoid—these pitfalls of decision-making.
I think Danny wanted, above all, to avoid a long decline, to go out on his terms, to own his own death. Maybe the principles of good decision-making that he had so long espoused—rely on data, don’t trust most intuitions, view the evidence in the broadest possible perspective—had little to do with his decision.
[..] “Right to the end, he was a lot smarter than most of us,” says Philip Tetlock, a psychologist at the University of Pennsylvania. “But I am no mind reader. My best guess is he felt he was falling apart, cognitively and physically. And he really wanted to enjoy life and expected life to become decreasingly enjoyable. I suspect he worked out a hedonic calculus of when the burdens of life would begin to outweigh the benefits—and he probably foresaw a very steep decline in his early 90s.”
Tetlock adds, “I have never seen a better-planned death than the one Danny designed.” [..]
Kahneman knew the psychological importance of happy endings. In repeated experiments, he had demonstrated what he called the peakend rule: Whether we remember an experience as pleasurable or painful doesn’t depend on how long it felt good or bad, but rather on the peak and ending intensity of those emotions. [..]
Kahneman’s friend Annie Duke, a decision theorist and former professional poker player, published a book in 2022 titled “Quit: The Power of Knowing When to Walk Away.” In it, she wrote, “Quitting on time will usually feel like quitting too early.” [..]
As death approaches, should we make the best of whatever time we have left with those we love the most? Or should we spare them, and ourselves, from as much as possible of our inevitable decline? Is our death ours alone to own? Danny taught me the importance of saying “I don’t know.” And I don’t know the answers to those questions. I do know the final words of his final email sound right, yet somehow feel wrong:
Thank you for helping make my life a good one.”
Jason Zweig, Wall Street Journal, 2025.3.15