LONDON — For more than a century, she lay hidden beneath one of Pablo Picasso's most famous works.
But now the nude portrait of a crouching woman has been brought to life by an artificial intelligence-powered software trained to paint like the legendary artist.
Picasso is believed to have reluctantly painted over the work at a time when resources were scarce. Its recreation has drawn global attention and praise, but also landed the two students behind the AI project in potential legal trouble — highlighting the challenges posed by efforts to give old art new life using technology.
At the heart of this dilemma is the question of ownership, both legal and cultural, as well as the ethics of using modern methods to uncover, reproduce or complete works of art long after their original creators are dead.
From Picasso’s “The Lonesome Crouching Nude,” as the long-hidden painting has been dubbed, to Beethoven’s unfinished 10th symphony, recent weeks have brought the issue to the fore.
Earlier this month, AI experts Anthony Bourached and George Cann prepared to unveil their revival of Picasso’s hidden painting.
The original was discovered hidden under Picasso's 1903 masterpiece ‘The Blind Man’s Meal’ after that piece was X-rayed in 2010.
Bourached and Cann, who are both doctoral researchers at Britain’s University College London, sought to recreate the hidden nude by training AI to replicate Picasso's brushstrokes using an algorithm that allowed it to analyze dozens of his past works.
Using the 2010 X-ray as a starting point, the AI was able to reproduce a version of the painting, which was given texture and printed onto canvas using three-dimensional printing technology.
Their work represented a “new frontier” for the use of AI in the art world, Bourached told NBC News in a phone interview Oct. 12, a day before the piece was set to be unveiled at the Deeep AI Art Fair in London.
Art is a way of “documenting information” about moments in time, including in an artist’s life, he said. “And I think (this) is a new frontier. I think the future of AI helps us to understand ourselves better as a society.”
That evening, however, the duo received a letter from U.K. representatives of Picasso’s estate demanding that they cancel the unveiling and cease any use of Picasso’s works, citing an “infringement of rights.”
“If I’m honest, I think it’s a bit sad our innovation has been stifled in this way,” Cann said on Oct. 13, as the unveiling of the piece was called off hours before it was meant to go on display.
The pair said they hoped to seek resolution with Picasso's estate on the matter.
However, Claudia Andrieu, the head of legal affairs for Picasso’s estate, suggested such an agreement was unlikely, in a statement sent to NBC News on Thursday.
"Disclosing a work by Picasso is a matter of copyright and in particular moral rights," she said. "It is a timeless right, which belongs only to the heirs of the author.
"Moreover, this Artificial Intelligence that 'learned' to paint 'like Picasso' will never have the sensitivity of a painter whose creativity is expressed in front of each blank canvas," Andrieu said.
"The 'result' of this Artificial Intelligence is not a work and it is indecency to say otherwise," she said. "A machine cannot replace an artist, nor complete the work of an artist who has abandoned it on the way of its creation."
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In response, Bourached said the estate's claim was "mistaken on points of law, ethics, philosophy, machine learning and art."
"The right to imaginative reinterpretation — intuitive or machine assisted — is not for Succession Picasso or anyone else to deny," he said in a statement. "This is a right Picasso himself assumed in including artefacts made by others in his paintings."
In a separate statement, Cann added that the pair had “not claimed to have recreated an actual work by Pablo Picasso,” but a “possible reconstruction of the piece hidden beneath Picasso’s 1903 The Blind Man’s Meal.”
“The actual work in question remains concealed beneath layers of paint," he said.
Ty Murphy, a Picasso specialist at the London-based Domos Art Advisors said it would be a "travesty" to hide the piece "away without showing it to the world."
"They actually brought a Blue Period Picasso back to life so we can get to see what it would have looked like before it would have been painted over," he said.
Asked about the possibility of the Picasso estate pursuing legal action, Murphy questioned: “Are they going to sue AI?”
Emily Gould, a senior researcher at the Institute of Art and Law, was not convinced by that argument, however.
While there are ongoing discussions around the world about artificial intelligence and copyright law, she said, as it stands "in the U.K., AI as such is not treated as a being or something you can sue."
Therefore, it would likely be that those behind the project and displaying the piece would be on the hook.
And because Picasso's works are "already in copyright," she said, "generally, you would need to get consent to reproduce those works."
Bourached and Cann had raised an "interesting argument" by defending their piece as an imaginative reinterpretation but the fact that it was based on initial x-rays of Picasso’s work could potentially be “problematic,” she said.
But, of course, it’s not just legal questions that hang over such efforts.
Individuals looking to engage with old art using technology risk entering “murky waters” ethically too, said Selin Nugent, an anthropologist and assistant director at the Institute for Ethical AI.
In the case of the lost nude, she said, she could see where the Picasso estate was coming from in wanting to maintain “a consistent representation of the artist that is true to his life and how he wished to be represented,” in addition to protecting the value of his work.
Still, Nugent said that in this case, AI was used as a “forensic tool to build knowledge,” which she believed was ultimately a worthy cause and an ever-growing function of the technology.
Murphy, who has dedicated his career to the study of Picasso paintings, said he felt confident that the artist would have been glad to see a lost work recreated, but acknowledged it was difficult to predict how artists might feel about such re-creations of their works.
These legal and ethical questions are ones Ahmed Elgammal, who heads the Art and Artificial Intelligence Laboratory at Rutgers University in New Jersey, has personally had to weigh.
For the past two years he has helped lead a project to "finish" Ludwig van Beethoven's last symphony.
And last week a version of what it may have sounded like rang out at a concert in the composer’s hometown of Bonn, Germany, thanks to an AI-imagined ending.
Beethoven unveiled what would become his final complete masterpiece in 1824, but was believed to have been working on a tenth symphony in the years before his death in 1827.
Symphony No. 10 was first partly imagined in the 1980s, but Elgammal's team sought to answer one of the music world's biggest what-ifs. The team trained AI to compose music in Beethoven's style by analyzing his existing works while Austrian composer Walter Werzowa, who co-led the project, added a human touch.
"There were moments when I was wondering ... moments when I was crying. It was just beautiful," Werzowa said.
The composer added he believed AI had captured the "essence" of Beethoven's work.
Yet, for Melanie Torres-Meissner, an American violinist in the Beethoven orchestra in Bonn, the AI version is "missing something."
"I find the spirit of Beethoven missing … the humanity of Beethoven is missing," she said.
Similarly, Murphy said that any Picasso expert would likely be able to tell that the AI replica of the lost painting is artificial.
AI is still "in its infancy," he said, though he believes that soon "you will not be able to tell the difference."
Still, he said, he hoped that technology would continue to be used to restore and revive lost works around the world.
"Look at … all the paintings that the Nazis destroyed" during World War II, Murphy said. "Now, wouldn't it be wonderful if artificial intelligence was able to create a rendition of all those missing pieces that have been consigned to history?"
"Some might scoff at the idea," he said. "I find it extremely exciting."