For centuries, the three faces of the Ashura Buddha have looked out from inside the Kofukuji Temple in the ancient Japanese city of Nara. But when devotees and scholars gaze back, what do they see? Or, at least, what do they think they see?

Long and thin with six arms and three heads, the 1,200-year-old masterpiece is both revered as an object of faith and admired as a work of art. It’s even been officially classified as a national treasure. But just as people in the West have long wondered about the enigmatic smile of the Mona Lisa, Ashura’s subtle facial expressions have puzzled people in Japan.

Now researchers have a new way of understanding it and other precious Buddhist statues. By using artificial intelligence (AI) tools, they are unraveling some artistic mysteries.

Take, for instance, the question of whether Ashura is happy or sad. As it turns out, that depends on how you look at the statue. From the right, it appears sadder, and from the left, happier. Also, Ashura’s appearance is that of a 23-year-old, says Professor Syun’ichi Sekine, of Nara University’s Department of Cultural Properties.

For much of last year, Sekine and a team of 18 students analyzed photographic images of more than 200 ancient Buddhist statues, including Ashura, with Azure Cognitive Services’ Face API – an AI tool that is increasingly being used in advertising and entertainment, as well for chatbots.

For the Nara University project, a pre-trained AI system recognized eight types of human expressions: anger, contempt, disgust, fear, happiness, neutral, sadness, and surprise.

With this capability, the researchers were able to sidestep the subjective interpretations of believers and others made over generations and establish what the artists were really trying to convey when they created the statues.

“These Buddhist statues are objects of religious belief. So many Japanese people see different facial expressions according to the mental or emotional state of each worshiper,” Sekine explains.

“We wanted to look at how the statues came to be shaped by their sculptors before they were enshrined in religious surroundings as objects of worship. In other words, we wanted to figure out what the sculptors used as models – the kind of human expressions they used.”

Traditionally, Buddhist statues are not supposed to portray age or emotion, and, except for guardian deities, they are not supposed to have genders. “Their makers were sometimes explicitly told to avoid giving their works any human facial expression or emotional content… embodying the view of Buddha as definitely not being human,” Sekine explains.

According to tradition and belief, the more “indifferent” the face of a Buddha statue looks, the more “perfect” it is. Despite this, scholars believe that the sculptors were often influenced by the tastes and styles of their times as well as the wishes of those who commissioned the statues. For example, joyous expressions were fashionable in one period while angry expressions were favored in another.

As they strove for academic objectivity, the Nara University team were well aware of the sensitivities surrounding their project. It was one reason why they chose AI as a research tool.

“Studying this sort of art sometimes requires researchers to judge religious idols. That might mean crossing a line that many believe should not be crossed,” Sekine says. “If people believe it is imprudent for human beings to judge Buddha, then maybe entrusting the process to AI is a way of objectifying such judgments, making them ‘inorganic.’”

The aim of the project was “to provide people with a means for reaffirming the beauty of Buddhism.” And, Sekine believes that new digital technologies will be increasingly used in cultural research.

“Initiatives that combine Buddhism with AI and other present-day technologies are beginning to emerge, albeit, gradually. We think that new approaches to Buddhism through technology are important ways of making Buddhism attractive, particularly to younger generations.”

As a bonus from their research, the team has created a Japanese language website where people can upload facial photos of themselves and have these matched to statues with similar expressions. It’s a way for 21st-century devotees to make personal connections with this ancient art.

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