"The book will be called Zhao Wen Dao Ji and is based on one of Confucius' sayings that 'he who fully realizes the truth in the morning may die without regrets in the evening'."

I had visited his modest Beijing apartment, eager to extract as much information as soon as possible, lest he should suddenly tire and my chance be gone.

Two hours later his nanny opens the door as if to gently indicate it is time for Zhou to have his lunch. Not once had the man himself indicated he wanted to stop. In fact, he beams huge smiles at us as we leave and poses happily for photos.

Is he proud of his life, I ask. "I am not proud," says this follower of Confucius. "But I am happy."