The Opal Deception

The story is told from the point of view of Winston Smith, a functionary of the Ministry of Truth whose work involved the "correction" of all records each time the "Big Brother" decided that the truth had changed. The Party slogan said that "Who controls the past controls the future: who controls the present controls the past", and they applied it constantly by "bringing up to date" the past so as to make it coincide with whatever the Party wanted.