On an early afternoon at Sera monastery, just outside Lhasa, Tibetan monks debate theology in time-honoured tradition across a leafy sunlit courtyard.
Tourists now outnumber monks in Sera monastery
The monks debate in pairs - one seated on the ground barking out questions, the other lunging forward, slapping his hands together in his rivals' face as he parries back answers.
It could be a scene from centuries past, were it not for the presence of a grinning tourist standing alongside a monk, mimicking his movements for a holiday snap.
Mainland Chinese tourists are beating a track to Tibet in ever-increasing numbers.
The monks in Sera monastery are now outnumbered by tourists, capturing their every move on camera, and turning serious theological practice into a circus.
Religious institutions in Tibet are increasingly finding their timetables driven by tourist schedules and visitor demands. Even senior monks act as glorified tour guides.
But some say they do not mind the distraction.
"When people come here, sometimes they donate money or make offerings. So tourism is good for us economically," said Phurbu Tsering, the deputy director of Sera monastery.
The profit motive means tourists are beginning to take priority over ordinary Tibetan pilgrims.
This is most obvious at the Potala palace, the huge hilltop landmark that was once home to the exiled Tibetan leader, the Dalai Lama, and still holds his predecessors' remains.
The palace is an important pilgrimage site for Tibetans, yet they are only allowed to climb up the steep slopes to the building for two and a half hours a day.
"Pilgrims can come to the Potala any day that they like," explained Champa, the director of the Potala palace.
Pilgrims can only visit the Potala palace at certain times
"Why can't they come in the morning? Because there are quite a lot of tourists visiting in the morning," he said.
The answer must also lie in the revenues accruing to the Potala.
Pilgrims pay just 1 yuan (12 US cents) for their tickets, a hundredth of the price paid by tourists.
There is no doubt that tourism is bringing much-needed funds to Tibet.
Officials say that last year tourists contributed $55m to Lhasa's economy.
For mainlanders reared in atheist China, Tibet's religious devotion is one of the lures attracting them to the Land of the Snows.
But as well as money, these Chinese visitors bring a ruler's mentality.
"We all have yellow skin, black eyes and black hair. Tibet is part of China," said one young female tourist.
That might be the Chinese government's view, but for many Tibetans, their allegiances lie with their exiled spiritual leader the Dalai Lama - a man Beijing sees as a traitor.
About 30,000 pilgrims went to this year's annual Shoton festival
Monasteries have traditionally been a hotbed of dissent, so China has tightened its grip on these religious institutions.
"There's an overall deterioration in human rights in Tibet, certainly over the last few years," said Anne Callaghan from the Free Tibet Campaign.
"It's part of an overall pattern of targeting religious institutions, increasing patriotic re-education campaigns and the like, because China sees religious expression in Tibet as being a threat to its legitimacy."
At this year's Shoton festival at Drepung monastery outside Lhasa, an enormous Buddhist picture was unveiled on a hillside.
The event may have attracted many tourists, but for the 300,000 Tibetans attending the festival, it was more about expressing their distinct Tibetan identity.
"I'm wearing these traditional clothes to keep Tibetan history alive," said Wu Jin, an elderly man with a long plait and a traditional Tibetan garment thrown over one shoulder.
"I've brought my grandchildren to learn about Tibetan history," said Karma Lhamu, who was also wearing traditional dress. "Religion and politics are both important, but religion is more important."
China may be hoping that its strategy of combining hard control with soft tourist dollars will win loyalty in Tibet, eroding its religious fervour.
But Tibetan hearts, it seems, are not so easily bought.