Happiness guru Shawn Achor will appear on Oprah’s “Super Soul Sunday” this Sunday at 11 a.m. ET. (Courtesy of Harpo Studios, Inc. / George Burns/Courtesy of Harpo Studios, Inc. / George Burns)

Rachel Dry is a features editor in The Washington Post’s Style section.

The happiness guru looks relaxed. His bright red shoes echo the brightness of Oprah’s pink shirt and the flowers behind them. It’s the sort of color palette that is either carefully planned or happens naturally when one of you is a happiness guru and the other one of you is Oprah.

In the promo for this episode of her “Super Soul Sunday,” the talk-show impresario promised in trademark sing-song that this would be part one of a two-week conversation “that’s gonna make ya happier!”

Because that is what Shawn Achor does. Before setting out to lift the spirits of Oprah’s viewers — the second installment airs Sunday on the OWN network — he wrote two best-selling books on happiness. His TED talk on “the happy secret to better work” has been viewed 7.6 million times — it’s among the site’s 20 most popular lectures, beating out a talk by Steve Jobs.

Yet long before all that, the man whose expert counsel is now sought by Fortune 500 companies lived upstairs from me in a dorm. And happiness, whatever that means, seemed very far away.

I first met Shawn my freshman year in college, in the fall of 2000, when he was a divinity school graduate student. In exchange for on-campus housing, he was tasked by the school with providing “important personal and social counsel as first-year students adjust to independent life in the College.” Also, if memory serves, he hosted study breaks. With cookies.

I hung out at some of those study breaks. And Shawn and I chatted regularly in the halls. Yet, that year, I was floundering.

Part of the problem was that I’m not exactly hard-wired for optimism and have often looked for help on the happiness front. In my early 20s, I went to see a life coach. At one point I said the following sentence out loud: “Well, maybe I want to be a midwife.” Which is a noble profession but also, in my case, a very specific cry for help. The life coach offered to see me pro bono — the way immigration lawyers offer to help people fleeing genocidal regimes. Or me, just trying to figure things out.

When the future happiness guru and I were living in the same building, my problem had a lot to do with college itself. I’d grown up near a college campus, and living among polar-fleeced collegiate idealists, as they tossed Frisbees and discussed the good they would do in the world, had led me to romanticize the college experience. Through my awkward slog of adolescence, I imagined that in college, everything would make sense and that I would become a better version of me.

Of course, the reality turned out to be rather different.

I knew enough to seek some professional help. I told one counselor that, among the things that made me feel like I was drowning, I found the dining hall overwhelming and was having trouble with out-of-control eating.

Her advice: “Have you tried using a smaller plate?”

Reading Shawn’s books and watching his TED talk recently, I began to wonder whether, if only he had known then what he knows now, and had been able to tell me about it when I was 18, I might have been a little less lonely, a little more healthy, a little less certain that happiness was some unknown destination in the future, certainly not attainable in the present.

In his first book, “The Happiness Advantage,” he defines happiness as “the joy we feel striving after our potential.” (When he repeated this idea to Oprah, he prefaced it by saying that its roots are in the work of the Greek philosophers he studied. She called it a “tweetable moment,” no doubt gratifying Aristotle.)

His definition is a savvy one, skirting ineffable notions of euphoria. Potential is more PowerPoint-ready, good for the Google executives and Swiss bankers he has coached in his consulting career.

After getting a master’s from divinity school, Shawn worked with positive psychologists as a research and teaching assistant. His writing is easy to understand, peppered with jokes and anecdotes from his travel, and his work essentially synthesizes scientific research while providing practical advice:

Write “gratitudes” — things you are grateful for — on a daily basis, and you can retrain your brain to look for the positive.

Don’t check your e-mail all the time if you are trying to concentrate.

But do write nice e-mails to people, praising them for their work or thanking them for their help. That can give you a boost.

Eliminate small obstacles to your goals.The examples he gives from his own life are going to sleep in gym clothes so he is workout-ready in the morning and keeping a guitar out in his room instead of in the closet so he is more likely to practice.

It all does seem relatively doable. The real problem, Shawn explains in his writing, his talk and to Oprah, is that we have to understand that happiness comes before success, not after. Because success is a moving target.

Being successful doesn’t make you happier; but being happier does make you more successful.

Oprah’s response to this insight: “I love it, I love it, I love it.”

One thing I have learned in the years since college is not to let regret fester. So I decided to call Shawn. To congratulate him on his accomplishments and to catch up a bit. Beyond that, I also wanted to say, as politely as possible: I feel cheated. Now you’re this expert, and I missed out. What could you have done to help me be happier in college?

“One of the things Oprah said to me, which is a crazy sentence — ” he started by saying, allowing that quoting Winfrey wisdom as delivered in person is indeed not something everyone gets to do. Oprah told him, possibly quoting someone else, in an aphorism echo-chamber: “Forgiveness is giving up hope that the past would be different.”

Okay. So I didn’t learn to be happy from the happiness expert when I knew him. Fine. Now what? The cure for that, Shawn said, is this: “What we have in the present is the ability to change how we thought about the past.”

I asked him what he would do differently now, if he were to go back in time and be in charge of a group of college freshmen again.

He said he’d try to have a “gratitude wall.” And to “encourage people to do meditation, tell students when they’re down to journal about a positive experience.”

I began to feel less cheated. I don’t think I would have been able to take gratitude-writing seriously at age 18. (“I’m grateful there are cookies at this meeting, because are you kidding me with this?”)

But most of all, he said, “I wish I had known at the time and could have verbalized to students: Happiness is more of a choice than we think it is.”

When Shawn and I were living in the same dorm, we actually had more in common than I thought. Specifically, the future happiness guru and I were both unhappy.

Shawn told me that he was going through depression himself in 2001 while attempting to counsel students.

He mentioned this to Oprah in the final moments of what was supposed to be a one-hour interview. They talked for another hour — it turned out that depression was something Oprah had struggled with, too.

Part of what got him out of his depression, he said, was using the tools of positive psychology (a useful coincidence for someone who now makes a living talking more than 100 times a year about positive psychology). Journaling, exercises in gratitude — “it taught me that our behaviors actually matter,” he told me.

Of everything Shawn said on the phone, and in the two books of his that I read, and in the TED talk that I’ve now watched half a dozen times, the most useful story he told me was about what happened when he met Oprah.

“She put up her hands — to be like ‘Hi, Shawn’ — but I couldn’t tell if she meant to give me a high-five or — ”

Or a hug? Was Oprah hugging him?

“I did this awkward — I grabbed her hands and didn’t know how to let go, so did this weird high-five hug that I couldn’t extricate from,” Shawn says, and I can picture it, a smiling man grasping Oprah’s hands, maybe swaying a bit in the California breeze. Mortified.

“It was hard to bring thoughts fully together,” he said, merely mortal, and awkward, and fumbling in Oprah’s presence, no matter how many gratitudes one practices.

As we all would be.

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