There are now an estimated 540 million CCTV cameras in China.Cameras watch citizens as they shop and dine. Cameras stare at residents as they leave home in the morning and return at night. In the office, cameras spy on workers inside toilet cubicles.And if you, the Chinese citizen, are particularly unfortunate, you may arrive home one day and find that a camera has been installed within your property. Supposedly a quarantine measure, it crouches there on the cabinet wall like a hostile creature that has somehow found its way in watching as you eat, watching as you watch TV; a silent, unwanted houseguest. Cameras also lurk in the homes of the mentally ill. The state considers them too volatile to live unmonitored, but no apparent thought has been given to the special torment produced by an ever-present eye during periods of psychological distress.