One thing is sure, however. In that century the remarkable, softly spoken knight has built memorials that have enriched the lives of millions. He has done it with humility, and many acts of quiet philanthropy have been carried out with the insistence that nobody knows he is involved.

In about 1984, for example, I returned from a trip to the remote Yunnan borderlands. I was interviewing Sir Run Run about his programme of funding new schools and medical universities on the mainland. I happened to mention I had been to an inspiring movement in Yunnan where Ma Haide, the doctor behind the successful programme to wipe out venereal disease on the mainland, was making great strides in eliminating the ancient scourge of leprosy.

The flesh-rotting disease had eaten the bodies of Chinese for 3,000 years. Dr Ma had led the barefoot doctors who spread news that it was curable and not easily passed on. But these teams of medical pioneers could not reach the villages in sorry isolated pockets of the distant hills where leprosy was still an active plague.

'What do they need?' Sir Run Run asked.

I said the greatest call was for four-wheel drive vehicles to carry volunteers and equipment over the rugged, stony mountain tracks.

'Give me the telephone contact,' he said. 'But no publicity. None.' A few days later, the vehicles were waiting to be picked up in Guangzhou .

This was one of scores, hundreds of unknown examples of his instant response for a good cause. His giving was of two kinds. The first was instinctive. He saw a good cause and supported it. Then there was the much larger, in terms of funds, organised causes to which he contributed immensely.

In 1994, at the old Shaw Brothers movie headquarters in Clear Water Bay Road, he told me the Shaw Foundation he set up in 1975 was spending HK$160 million a year on building schools on the mainland. At that stage, it had constructed 266 institutions in 21 provinces. He had spent HK$800 million. He was still in first gear.

Last month, Professor Ma Lin, chairman of the Board of Trustees of Shaw College at Chinese University, estimated that the value of 7,500 school building grants to the mainland was now HK$40 billion. Of course, every tertiary institution in Hong Kong and lots of other scholastic enterprises have also benefited.

Sir Run Run not only possesses an almost bottomless well of money, but has the astute and shrewd mind of a canny businessman. He doesn't just give money. It is handed out in a carefully screened manner.

New schools are built but it is up to local communities and provincial and municipal governments to staff, equip and manage the new institutions. It's a balanced and sophisticated plan that ensures all money is well spent. 'This is the best way to help the motherland,' he said. 'Education is the key.'

That focus on learning ranges from local primary schools to medical and technical universities.

Sir Run Run was busy as a social activist long before he started the foundation. He worked in many fields and his influence spread widely through the community.

But where does the money come from that supports these many initiatives? Most of it springs, originally, from entertainment. From that came real estate. Then land development. Then the extension from simple but effective movies to television. Then it led into businesses of all kinds. Behind his appearance of an elderly kindly man is his role as one of the great dragons of overseas Chinese business.

It began when he was a child early last century and his elder brother (of six sons) was a lawyer who ran sing-song and dance halls in Shanghai for his personal entertainment. As the first hesitant flickering lights of silent movies were seen in the city, Runji Shaw and another brother, Runme, were already in the business.

His school days at an American international school ended when he was 19, and Sir Run Run was sent south to Singapore. His instructions were to help Runme establish outlets for the increasing number of improving Chinese-language films pouring out of the Shanghai studios.

The target audiences were the swelling, prospering Chinese communities in then Malaya, Burma, the Dutch East Indies, the Philippines and British Borneo. They were a linguistic stew of Hakka, Cantonese, Hokkien, Hainanese, Guangxi and all the other coastal and river dialects. The films - thank goodness, Sir Run Run laughed - were silent.

They had one broken-down old cinema in Singapore. Mostly, the customers lived in lonely tin mining settlements, lumber camps, fishing ports and the few small towns such as Ipoh. Sir Run Run and his assistants would load projectors and screens onto the back of trucks and rumble through the jungles.

On the edge of town, they would set up temporary outdoor cinemas and pray it would not rain. They would hire chairs from schools and clubs. The shows were always overflowing. They charged people who couldn't find a seat a few cents. Later, many of these plots on the fringe of towns were developed as tin-roofed cinemas. The canny brothers then bought the cheap land surrounding them; people who watched an exhaustive two-hour drama needed food and drink. These in turn developed into shopping centres.

Many years later, I asked Sir Run Run why the previous year the Shaw movie company had not made a single movie but profits for the public company had soared. 'Real estate around the old movie theatres where we showed other people's films,' he chuckled.

In the 1930s came a revolutionary movie change. First came soundtracks.

What about local language films for Indonesians? They swept Java. Sir Run Run was convulsed one night at his home as he explained to my wife and I the intricacies of making movies for the large Tamil population that tapped the rubber trees. You just took a movie, Chinese or Malay, and dubbed it in Tamil, he said, and then you put in another hour of film of a movie flowing silently or some other quiet natural view and the audience was delighted.

In 1939, Sir Run Run returned to Shanghai to report to his elder brother, Runji. There were, by then, 139 Shaw Brothers theatres in Southeast Asia. He returned to Singapore. It was the last time the brothers met.

During the long years of agony after the Japanese invasion in 1932, the company distributed many patriotic movies backing the resistance against the invaders. Sir Run Run went underground but the military police tracked him down. He decided to tell the Chinese-speaking agents of the dreaded Kempetei the truth. He figured he might as well do it before he was tortured. After 10 days, they let him go. In the war, the family lost everything they had built in Southeast Asia.

He negotiated with the Hong Kong government for the enormous headland at Clear Water Bay for 45 cents a square foot, and started the Hong Kong studios. He came to live here permanently in 1959. How many movies did he make there? In 1994, he pondered: 'Maybe 800, maybe 900.' They changed the movie world. Action films, sword fights, kung fu ... the money rolled in.

There was the incredible, unbelievable Wang Yu, the one-armed swordsman. The Taiwanese star got into more trouble on the streets of Kowloon than he did in some of his movies. Three pictures of different genres might be shot at one time.

There were lights, cameras and action throughout the night.

Then the money began to flow out to Sir Run Run's beneficiaries. He was appalled to find that old superstitions still clamped firmly on many Hongkongers. They would not donate blood or organs. People were dying because the blood banks were empty. In an emergency, police or soldiers were lined up and virtually ordered to give blood.

Sir Run Run lined up some of his most shapely starlets and frog-marched them to blood collection centres. There was nothing voluntary about this. The result was a series of stories and pictures in newspapers and his own TVB shows. Hongkongers in their tens of thousands followed their screen idols' example to give blood. By the mid-1990s the blood donation crisis was over, under the stewardship of Sir Run Run. Then came the Arts Festival. It was ailing and Sir Run Run stepped forward to save it. It is now an institution of pride for our community, squashing the haughty notion of many expatriates that Hong Kong is a cultural desert. Then came the Shaw Foundation and the cash that had been so exactingly and exhaustively raised by business enterprises was being given away in ever-increasing amounts for diverse projects. The Shaw Prize, regarded as the Nobel Prize of Asia, has since 2004 made annual awards of up to US$1 million for astronomy, mathematics, and life and medical science.

With his Knight of the Thistle order from Britain's Queen Elizabeth and the Grand Bauhinia Medal from the SAR government, not to mention the admiration and gratitude of many thousands of admirers, Sir Run Run's contributions to society have been officially recognised.

But I believe he deserves more, far, far more, than medals. He is a man who has planned conscientiously and well to donate much of his self-made fortune to the people. He is a national living treasure and we as a society are fortunate indeed to have him as one of our leading citizens.

Happy birthday to you, Sir Run Run, whenever it was.