Oprah Winfrey turned her Cannes Lions appearance into a call for creators to use their platforms for good, talking with festival chair Phil Thomas about philanthropy, legacy and her improbable path from rural Mississippi to becoming one of the most powerful self-made figures in media.

Inside the Lumière Theatre, where she received the festival’s LionHeart Award, Winfrey used the stage to meditate on purpose and responsibility before an audience of advertising, media and creator-economy figures. She also reflected on the school she built in South Africa, her friendship with Maya Angelou, her childhood in Mississippi and her memorable interview with the late Whitney Houston on “The Oprah Winfrey Show.”

“We did the whole, ‘Hey girl, how you doing?’ greeting thing and then I stopped the cameras and I went behind stage and I said, ‘So tell me, what do you want to happen here? And I’m gonna tell you what I want to happen here,'” Winfrey said. ” And that was one of the most powerful interviews.”

She said Houston later returned to the show to perform and had relapsed in her addiction. “I had such trust from ‘The Oprah Show’ audience … I think it was [Houston’s] last show with us, and she had gone back on drugs,” Winfrey said. “The first interview I did with her when we’d gone behind stage and I asked her about her intention, she was clean, but the day she came to my show then to perform in front of the audience, she was not, and she fell off of the stage.”

Winfrey said she knew the moment could have been devastating if it became public. “I knew that if that story got out … she would be destroyed by that,” Winfrey said. “And so even though the audience was there and the audience had cameras, I begged them not to put those pictures out because it would ruin her life, and they did not. That would not happen today, I can tell you that,” Winfrey added. Houston died on February 2012 at the age of 48 after an accidental drowning.

Elsewhere in the conversation, Winfrey appealed to creators’ sense of responsibility and emphasized that influence carries obligations.

“What you’re doing is not just making money and creating influence for yourself … it’s the subsidiary thing that happens from living,” she said. “But you have a bigger calling in life … Your bigger job here on the planet is to be the best human being you can be, not the best creator, not the best talk show host, not the best podcaster, but how are you evolving into what creation intended for you to be?”

Much of the conversation centered on the origins of her philanthropy and the personal experiences that shaped it. Asked how she decides who to help and how to help them, Winfrey traced the impulse back to her own childhood, recalling a Christmas when her family had nothing and nuns arrived at the house with gifts.

“It wasn’t the gift, it was the fact that they showed up,” Winfrey said. “They showed up and they let a 12-year-old girl know that I mattered.” The desire to give other children the same sense of being seen drove her decision to launch the Oprah Winfrey Leadership Academy for Girls in South Africa.

“So whatever disadvantages you’ve had in your life, the reason you had those disadvantages is not because the universe or the life force is trying to punish you, it’s because it’s trying to grow you to the next level,” Winfrey said. “It’s trying to teach you. So whenever challenges come in your life, and I’ve said this over the years to all my audiences, the challenge isn’t there to just mess with your mind, to mess you up, the challenge is there to say, ‘What is this here to teach me so I can grow to the next level?'”

She said her own background made the work in South Africa feel intensely personal. “I was a poor girl in Kosciusko, Mississippi, on a dirt road, no running water, no electricity,” she said. “I found girls who were in villages, same circumstances, and so it felt like I was literally mirroring my own life, giving an opportunity to kids who come from the same thing.”

Winfrey said the school had changed the trajectory of its students’ lives, citing a recent survey conducted by the University of Cape Town. “What they said about what we have done at this school is that we have interrupted poverty,” she said. “And we have done that. Because that was my intention. My intention was to change the trajectory of their lives.”

Winfrey also recalled a lesson from Maya Angelou, who challenged her when Winfrey told her the school would be her greatest legacy.

“Nobody expected anything would come from a Black girl born out of wedlock in Mississippi in 1954, and they only had sex one time! Thank goodness they did,” she told the crowd, sparking laugher.

“It doesn’t matter how you got here, the fact that you are here is such a miracle,” she continued.