Playing notes on her piano, she demonstrates for Steve why whole numbers sound pleasing, why octaves are mathematically imperfect, and how math underlies musical composition. Sarah, a professor at the University of London and Gresham College, also talks with Steve about the gender gap in mathematics and why being interested in everything can be a problem.

49. Mathematician Sarah Hart on Why Numbers are Music to Our Ears

Freakonomics co-author Steve Levitt tracks down other high achievers for surprising, revealing conversations about their lives and obsessions. Join Levitt as he goes through the most interesting midlife crisis you’ve ever heard — and learn how a renegade sheriff is transforming Chicago's jail, how a biologist is finding the secrets of evolution in the Arctic tundra, and how a trivia champion memorized 160,000 flashcards.

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Society & Culture

Personal Journals

History

Philosophy

Places & Travel

Monica Bertagnolli went from a childhood on a cattle ranch to a career as a surgeon to a top post in the Biden administration. As director of the National Institutes of Health, she’s working to improve the way we find new treatments — despite regulatory constraints and tight budgets.

129. How to Fix Medical Research

Nobel laureate, bestselling author, and groundbreaking psychologist Daniel Kahneman died in March. In 2021 he talked with Steve Levitt — his friend and former business partner — about his book "Noise: A Flaw in Human Judgment" (cowritten with Olivier Sibony and Cass Sunstein) and much more.

EXTRA: Remembering Daniel Kahneman

Google researcher Blaise Agüera y Arcas spends his work days developing artificial intelligence models and his free time conducting surveys for fun. He tells Steve how he designed an algorithm for the U.S. Navy at 14, how he discovered the truth about printing-press pioneer Johannes Gutenberg, and when A.I. first blew his mind.

128. Are Our Tools Becoming Part of Us?

After Haiti’s devastating earthquake, Rajiv Shah headed the largest humanitarian effort in U.S. history. As chief economist of the Gates Foundation he tried to immunize almost a billion children. He tells Steve why it’s important to take big gambles, follow the data, and own up to your mistakes.

127. Rajiv Shah Never Wastes a Crisis

"The Power of Habit" author Charles Duhigg wrote his new book in an attempt to learn how to communicate better. Steve shares how the book helped him understand his own conversational weaknesses.

49. Mathematician Sarah Hart on Why Numbers are Music to Our Ears

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