George Orwell devised the word 'unperson' to describe someone who had so offended official thought, he or she was vaporised - not just liquidated but wiped from the record for eternity. That way the unperson couldn't set a bad example. All memory of the impertinence would be forgotten, Comrades! ... When a Politburo member called Nikolai Yezhov, People's Commissar for Water Transport, fell out of favour with Joseph Stalin in 1940, he was not just killed. A photograph of him beside Stalin in happier days was doctored to remove all trace of the unfortunate Yezhov. It was as though he...