Among the numerous quotations and slogans woven into Francis Ford Coppola’s idea-rich, open-hearted and unabashedly optimistic "Megalopolis," one particularly resonates with the director: "When we leap into the unknown, we prove that we’re free."

"That’s me making this film," Coppola said, speaking on a hotel terrace in Cannes the day after "Megalopolis" premiered at the French festival. "To all of the studio big shots, I proved that I’m free and they’re not. Because they don’t dare leap into the unknown. And I do. That’s the only way to prove that you’re free."

Coppola pauses and then adds, with a grin. "I don’t recommend it."

"Megalopolis," Coppola’s first film in 13 years, has been called many things since it was unveiled in Cannes. A folly. A disaster. An audacious, self-financed gamble. What it is, regardless of whether all its strange parts function smoothly together, is a colossal personal statement by one of America’s most visionary filmmakers, about having the daring to be visionary.

It’s no small step but another giant leap by Coppola, 85, who feels so strongly about what "Megalopolis" encapsulates that he’s spent some four decades pursuing it. After the credits rolled at the premiere and the crowd stood applauding, Coppola grabbed the microphone to extend its message, pleading for "one human family" and "the children."

"My dream would be that this movie could be seen on New Year’s Eve and people would – instead of saying I’m going to lose weight or I’m not going to smoke anymore or I’m not going to cheat on my wife – talk about: Is the society we’re living in the only one available?" Coppola said. "How can we make it better? And if they talk about it, they will. That’s my dream."

In "Megalopolis," Adam Driver plays Cesar Catilina, a Roman emperor-like figure with the power to stop time in a futuristic New York. He’s an inventor who wants to build a new New York metropolis with a material he’s created called Megalon. In sensibility, he’s more like an artist, though. Cesar quotes "Hamlet," as well as Emerson, Marcus Aurelius and Ovid. You can't help but notice that he is a little like Coppola.

At the press conference in Cannes, Laurence Fishburne, who co-starred all the way back in Coppola’s "Apocalypse Now," recalled that Coppola "has always talked about stopping time."

"Even before he was talking about the movie, he would say, ‘I can stop time. I’ll show you,’" said Fishburne. "I used to sit and overhear conversations you had with Eleanor about that."

Coppola, who leaned on a cane or his granddaughter Romy Mars wherever he went in Cannes, is now more acutely aware of his limitations when it comes to time. Eleanor Coppola, his wife, died in April. "Megalopolis" is dedicated to her. "Sixty years we were together," he said, shaking his head. "Can you believe it?"

Time is much the subject of "Megalopolis," a movie 40 years in the making which Coppola said he first began seriously thinking about, he said, after completing 1997’s "The Rainmaker." He wanted to withdraw from his career and devote himself to more experimental pursuits.

"During that time, my thought was that I had used many styles, ‘Apocalypse’ was a wild style, ‘The Godfather’ was very classic - I wondered what my style might be in the future," Coppola said. "I had curiosity for what kind of film I might make when I was older. I kept a scrapbook of things I read. I made a collection of political cartoons. Those say a whole story in one image. That ultimately led to make a Roman epic set in modern America."

Coppola rewrote "Megalopolis" many times over in the years that followed. Not unlike Orson Welles, another American filmmaker who experienced unexpectedly enormous success early in his career who turned increasingly experimental as a filmmaker later in life, Coppola became fascinated with new possibilities for movies. He published some of his findings in the 2017 book "Live Cinema and its Techniques." Midway through "Megalopolis" screenings at Cannes, a man has walked onto the stage and, before a microphone, addresses a question to Cesar who looms above on the screen. It's like an injection of Megalon into the fabric of the film.

Driver was particularly invested in Coppola’s project, and the director considers him an important collaborator. Driver, who sat next to Coppola on the terrace, recalled that on the first day of shooting, Coppola told the cast: "We’re not being brave enough."

"For him to make a film like that at this point in his life I thought was a beautiful thing," Driver said. "He has conviction and it’s so ballsy. Why is it that he’s doing that at this point in his career and other people aren’t following that example?"

"Megalopolis" has had plenty of detractors. After Coppola screened it privately last month in Los Angeles, it was said to have no commercial prospects. Even the film's defenders grant that "Megalopolis" is juggling a lot, not always adroitly, in marrying the Roman past with a sci-fi future, debaucherous reverie and ultra sincerity.

But Coppola didn’t hesitate to, again, push his own money into "Megalopolis," investing some $120 million from his wine business to produce it. He’s been here before. Coppola famously put millions into "Apocalypse Now," a movie that also premiered in Cannes hounded by skepticism and rumors of production turmoil.

Is there something in Coppola that always needs to be going for broke?

"There are many times I’ve heard that Francis can only perform when he’s really up against it," Coppola said. "I don’t think that’s the case but maybe it is."

When Coppola and Driver first met to discuss the film several years ago, "We talked a lot about babies," Driver said. "That they’re constantly at work doing complex things even though it looks like they’re doing nothing."

"Every baby that’s being killed today in Sudan or Palestine – and a lot of them are being killed – it’s a potential Archimedes, a potential Einstein, a potential Mozart," said Coppola.

Here, Coppola returns to the subject of time. We aren’t fully comprehending our potential to change the world, he said. Though many today are plagued by apocalyptic and ecological anxieties, Coppola sees marvels all around. Electricity isn’t that old, he said. The internet was created in his lifetime. Fusion, Coppola muses, has enormous possibilities. We’re geniuses, he said.

"You never turn on CNN or open the newspaper to: ‘Human Being Is an Unbelievable Genius.’ But it’s true. How can you deny it?" Coppola said. "Think of what we can do. A hundred years ago they said man will never fly. Now we’re zooming around. So I ask myself: Why is it that no one dare say how great we are? There’s no problem that we’re facing that we’re not ingenious enough to solve."

It might be tempting to call all of this Coppola’s last testament and see "Megalopolis" – imbued with both childlike fascination and an old man's wisdom – as his wild cinematic goodbye. But, as his sister Talia Shire told reporters in Cannes, Coppola is always facing forward. He is already writing another script. "Megalopolis" might still be looking for distribution in North America, but, Coppola said, "I’m done with this."

"I’m making a new conglomeration," Coppola said, smiling. "It’s going to be unusual but it’s not going to be on this scale. I’m probably going to make it in England. It’s going to involve music and dancing. I’m a kid who was raised around Broadway. My parents were in New York theater."

"It’s going to be fun," Coppola adds. "I always tell myself: This is going to be fun."