The content and tone of the book benefited immeasurably from the early readers in my challenge network. Marissa Shandell and Karren Knowlton were exceedingly generous in reading more chapter drafts than any human should endure and unfailingly brilliant in improving them. I cannot thank them enough for enriching every section of the book with leads on characters, suggestions on flow, and refinements on language. Marissa went the extra mile to enliven concepts and synthesize practical takeaways. Karren went above and beyond to amplify complexity and diversify thought.

Reb Rebele, whose taste in ideas and prose is second to none, dished out the tough love that the early chapters needed and brought the seasoning that was missing from the denouements. Queen of signposting Grace Rubenstein offered sage guidance for helping readers see the forest in the trees and recognize thinking again as a habit that’s both timely and timeless. Dan O’Donnell helped me de-escalate my commitment to a series of dead ends and composed the written version of jaunty music to animate several key studies and stories.

Lindsay Miller—the human equivalent of the corpus callosum—led the cheer for more conversational snippets and richer illustrations of how the preacher, prosecutor, politician, and scientist waltz into our psyches. Nicole Granet expanded my thinking around how rethinking is relevant to every domain of life. Sheryl Sandberg sharpened the structure by convincing me to introduce the core idea before the organizing framework, and underscoring the value of well-placed bookends. Constantinos Coutifaris made the vital point that I needed to explore when it’s persuasive to preach, prosecute, and politick. Natalia Villarman, Neal Stewart, and Will Fields shared their expertise on antiracism. Michael Choo motivated me to go back to the drawing board on a chapter that wasn’t working. Justin Berg lent his creative forecasting skills to select and develop my most novel and useful insights, and also introduced me to the satisfaction of reverse alliteration (where sequential words share a last letter or syllable). Susan Grant, ever the English teacher, corrected grammar, caught typos, and fought with me about the Oxford comma. Sorry, Mom, that’s one thing I don’t plan to rethink.

Impact Lab reminded me once again how much teachers can learn from students. Vanessa Wanyandeh challenged me to consider how power imbalances affect which groups should be doing the majority of the rethinking and highlight whose responsibility it is to fight prejudice. Akash Pulluru fearlessly obliterated weak arguments and debated the principles of good debate. Graelin Mandel called for more information about when and why task conflict causes relationship conflict, and Zach Sweeney made a passionate case for expanding the role of the rethinking cycle. Jordan Lei pushed me to delve more deeply into the first-instinct fallacy, and Shane Goldstein took the lead in talking me out of the blank-page epilogue and into showing some edits and margin notes. Nicholas Strauch requested more context on how to ask good questions and defended the frog, and Madeline Fagen suggested more clarity on the distinction between beliefs and values. Wendy Lee advised me to go into more detail on expressing confident humility, Kenny Hoang suggested I demonstrate some of the interpersonal rethinking principles in my writing, and Lizzie Youshaei called for more analysis of when and why people are open to being wrong. Meg Sreenivas pointed out extraneous details, Aaron Kahane clarified confusing arguments, and Shaheel Mitra suggested the Edgar Mitchell quote.

I was lucky to have the support of top-notch teams at InkWell (shout-out to Alexis Hurley, Nathaniel Jacks, and Eliza Rothstein) and Viking (a group of people whose curiosity I miss every week I’m not writing or launching a book). Special thanks to Carolyn Coleburn, Whitney Peeling, Lindsay Prevette, and Bel Banta for their publicity prowess; Kate Stark, Lydia Hirt, and Mary Stone for their creative marketing; Tricia Conley, Tess Espinoza, Bruce Giffords, and Fabiana Van Arsdell for their editorial and production expertise; Jason Ramirez for art direction; Camille LeBlanc for wrangling; and Brian Tart, Andrea Schulz, Madeline McIntosh, Allison Dobson, and speed demon Markus Dohle for their ongoing support. Also, it was a delight to collaborate with Matt Shirley on the charts. Along with lending his characteristic cleverness and humor, he showed impressive patience in working to make sure they fit the content and tone of the book.

A number of colleagues contributed to this book through conversations. As always, Dan Pink gave excellent input on framing the idea and tips on relevant research. My colleagues at Wharton—especially Rachel Arnett, Sigal Barsade, Drew Carton, Stephanie Creary, Angela Duckworth, Cade Massey, Samir Nurmohamed, and Nancy Rothbard—modeled many of the principles in the book and led me to think again about many of the points I was making. I am also grateful to Phil Tetlock for the preacher-prosecutor-politician framework and referrals to Kjirste Morrell and Jean-Pierre Beugoms; Eva Chen, Terry Murray, and Phil Rescober for the analysis of Jean-Pierre’s forecasts; Bob Sutton for putting Brad Bird on my radar and analyzing his Incredibles leadership so perceptively, as well as Jamie Woolf and Chris Wiggum for opening the Pixar door; Karl Weick for introducing me to Mann Gulch; Shannon Sedgwick Davis and Laren Poole for putting me in touch with Betty Bigombe and sharing background on her story; Jeff Ashby and Mike Bloomfield for the referrals to Chris Hansen and Ellen Ochoa; Eoghan Sheehy for the connection to Harish Natarajan; and Douglas Archibald for recommending Ron Berger (props to Noah Devereaux and the Strive Challenge for that serendipitous conversation). Early on, Eric Best showed me how rethinking could help people raise the bar, and Brian Little, Jane Dutton, Richard Hackman, and Sue Ashford taught me to see rethinking as one of the great joys of being an organizational psychologist.

Every day, being a parent shows me that we all have the innate capacity to change our minds. As I finished writing this book during the pandemic, Henry wondered if the water supply might be affected and was eager to rethink where we get running water (Is there a tube that connects the ocean to our house? We might get an octopus!). When I asked how she convinces me to rethink things, Elena opened my eyes to a persuasion technique I had completely overlooked (Puppy dog eyes! Works every time!). When we were considering various optical illusions for the jacket of this book, Joanna came up with a better idea (What about a candle with a flame that’s water instead of fire?). I came away rethinking where creative ideas come from: if our twelve-year-old can come up with the perfect image for my book jacket, what else can kids do? I love how happily and effortlessly our children think again—and how they coax me to do it more often, too.

My deep gratitude goes to Allison Sweet Grant for her love, advice, and humor every step of the way. As always, she helped me rethink many of my assumptions and put up with countless trivial questions, random requests, and unnecessary debates. I still pronounce it man-aze, not may-o-naze, but she makes a compelling point that no one says “Please pass the man”; it’s “Please pass the mayo.” For the record, I don’t even like mayonnaise.