Dan Ariely

Dan Ariely (Hebrew: דן אריאלי; born April 29, 1967) is an Israeli-American author and professor of business administration at Duke University. He is the co-founder of several companies implementing insights from behavioral science. Ariely wrote an advice column called "Ask Ariely" in The Wall Street Journal from June 2012 until September 2022. He is the author of the three New York Times best-selling books Predictably Irrational, The Upside of Irrationality, and The Honest Truth about Dishonesty. He co-produced the 2015 documentary (Dis)Honesty: The Truth About Lies. Ariely's life, research, and book Predictably Irrational inspired the 2023 NBC television series The Irrational.

Since 2010, several of Ariely's statements and papers have received criticism regarding their reproducibility or reliability. In one case, a paper was retracted due to falsified data. Duke University has so far declined to comment on Ariely's culpability. In 2026, it was revealed that Ariely had a longstanding relationship with the American convicted sex offender and disgraced financier Jeffrey Epstein.