"The Japanese are a disease of the skin," he said, 'the Communists are a disease of the heart." Though the Communists and the Kuomintang were supposed to be allies, the Communists still had to work underground in most areas.

In July 1937 the Japanese began their all-out invasion of China proper. My father, like many others, felt appalled and desperate about what was happening to his country.

At about this time he started working in a bookshop which sold left-wing publications. He devoured book after book at night in the shop, where he functioned as a kind of night watchman.

He supplemented his earnings from the bookshop with an evening job as an 'explainer' in a cinema. Many of the films were American silents. His job was to stand beside the screen and explain what was going on, as the films were neither dubbed nor subtitled. He also joined an anti-Japanese theater group, and as he was a slender young man with delicate features, he acted women's roles.

My father loved the theater group. It was through the friends he made there that he first entered into contact with the Communist underground. The Communist stance about fighting the Japanese and about creating a just society fired his imagination and he joined the Party in 1938, when he was seventeen. It was a time when the Kuomintang was being extremely vigilant about Communist activities in Sichuan. Nanjing, the capital, had fallen to the Japanese in December 1937, and Chiang Kai-shek subsequently moved his government to Chongqing. The move precipitated a flurry of police activity in Sichuan, and my father's theater group was forcibly disbanded. Some of his friends were arrested. Others had to flee. My father felt frustrated that he could not do anything for his country.

A few years before, Communist forces had passed through remote parts of Sichuan on their 6,000-mile Long March, which ultimately took them to the small town of Yan'an in the northwest. People in the theater group had talked a lot about Yan'an as a place of camaraderie, uncorrupt and efficient- my father's dream. At the beginning of 1940 he set out on his own long march to Yan'an. He first went to Chongqing, where one of his brothers-in-law, who was an officer in Chiang Kai-shek's army, wrote a letter to help him cross Kuomintang-occupied areas and get through the blockade that Chiang Kai-shek had thrown up around Yan'an. The journey took him almost four months. By the time he arrived it was April 1940.

Yan'an lay on the Yellow Earth Plateau, in a remote and barren part of northwest China. Dominated by a nine tiered pagoda, much of the town consisted of rows of caves cut into the yellow cliffs. My father was to make these caves his home for over five years. Mao Zedong and his much-depleted forces had arrived there at different times in 1935 – 1936, at the end of the Long March, and subsequently made it the capital of their republic. Yan'an was surrounded by hostile territory; its chief advantage was its remoteness, which made it difficult to attack.

After a short spell at a Party school, my father applied to join one of the Party's most prestigious institutions, the Academy of Marxist-Leninist Studies. The entrance exam was quite stiff, but he took first place, as a result of his reading deep into the night in the loft of the bookshop in Yibin. His fellow candidates were amazed. Most of them had come from the big cities like Shanghai, and had looked down on him as a bit of a yokel. My father became the youngest research fellow in the Academy.

My father loved Yan'an. He found the people there full of enthusiasm, optimism, and purpose. The Party leaders lived simply, like everyone else, in striking contrast with Kuomintang officials. Yan'an was no democracy, but compared with where he had come from it seemed to be a paradise of fairness.

In 1942 Mao started a "Rectfication' campaign, and invited criticisms about the way things were being run in Yan'an. A group of young research fellows from the Academy, led by Wang Shi-wei and including my father, put up wall posters criticizing their leaders and demanding more freedom and the right to greater individual expression. Their action caused a storm, and Mao himself came to read the posters.

Mao did not like what he saw, and turned his campaign into a witch-hunt. Wang Shi-wei was accused of being a Trotskyite and a spy. My father, as the youngest person in the Academy, was said by Ai Si-qi, the chief exponent of Marxism in China and one of the leaders of the Academy, to have 'committed a very naive mistake." Earlier, Ai Si-qi had often praised my father as a 'brilliant and sharp mind."

My father and his friends were subjected to relentless criticisms and obliged to undertake self-criticisms at intensive meetings for months. They were told that they had caused chaos in Yan'an and weakened the Party's unity and discipline, which could damage the great cause of saving China from the Japanese and from poverty and injustice. Over and over again, the Party leaders inculcated into them the absolute necessity for complete submission to the Party, for the good of the cause.

The Academy was shut down, and my father was sent to teach ancient Chinese history to semi-literate peasants turned-officials at the Central Party School. But the ordeal had turned him into a convert. Like so many other young people, he had invested his life and faith in Yan'an. He could not let himself be easily disappointed. He regarded his harsh treatment as not only justified, but even a noble experience soul-cleansing for the mission to save China.

He believed that the only way this could be done was through disciplined, perhaps drastic, measures, including immense personal sacrifice and the total subordination of the self.

There were less demanding activities as well. He toured the surrounding areas collecting folk poetry, and learned to be a graceful and elegant dancer in Western-style ballroom dancing, which was very popular in Yan'an many of the Communist leaders, including the future prime minister, Zhou Enlai, enjoyed it. At the foot of the dry, dusty hills was the meandering, dark-yellow, silt-filled Yan River, one of the scores which join the majestic Yellow River, and here my father often went swimming; he loved to do the backstroke while looking up at the simple solid pagoda.

Life in Yan'an was hard but exhilarating. In 1942, Chiang Kai-shek tightened his blockade. Supplies of food, clothing, and other necessities became drastically curtailed.

Mao called on everyone to take up hoes and spinning wheels and produce essential goods themselves. My father became an excellent spinner.

He stayed in Yan'an for the whole of the war. In spite of the blockade, the Communists strengthened their control over large areas, particularly in northern China, behind the Japanese lines. Mao had calculated well: the Communists had won vital breathing space. By the end of the war they claimed some sort of control over ninety-five million people, about 20 percent of the population, in eighteen 'base areas." Equally important, they gained experience at running a government and an economy under tough conditions. This stood them in good stead: their organizational ability and their system of control were always phenomenal.

On 9 August 1945, Soviet troops swept into northeast China. Two days later the Chinese Communists offered them military cooperation against the Japanese, but they were turned down: Stalin was supporting Chiang Kaishek. That same day the Chinese Communists started to order armed units and political advisers into Manchuria, which everyone realized was going to be of critical importance.

A month after the Japanese surrender my father was ordered to leave Yan'an and head for a place called Chaoyang in southwest Manchuria, about 700 miles to the east, near the border with Inner Mongolia.

In November, after walking for two months, my father and his small group reached Chaoyang. Most of the territory was barren hills and mountains, almost as poor as Yan'an. The area had been part of Manchukuo until three months before. A small group of local Communists had proclaimed its own 'government." The Kuomintang underground then did the same. Communist troops came racing over from Jinzhou, about fifty miles away, arrested the Kuomintang governor, and executed him for 'conspiring to overthrow the Communist government."