In Consciousness Explained, Daniel Dennett identifies two types of post-experiential revision (revision of personal historical memories). Basically, these are two approaches to contaiminating the memory of a subject.1 To use his example:
Say you're a totalitarian government who needs to execute a public figure (or someone who will become a public figure on their execution). Assuming you have significant control of the media you have two options:
- Insert a story about a (non-existent) trial and guilty verdict into all available media archives.
- Execute them.
- In all the news stories about the execution, refer the trial promenently, with lots of citations to archival material.
Anyone who doesn't remember the trial will be encouraged to check their facts. Provided that your government has sufficient power, they won't press the matter and will convince themselves of their error.
- Create evidence and hire actors as witnesses (fake defence lawyers optional).
- Stage a show trial ending in a guilty verdict that is highly publicised.
- Execute them.
Anyone who questions the validity of the prosecution's evidence will have to question their entire legal system. Provided that your government has sufficient power, only the insane would have such conspiracy theories.
Dennett points out that after the fact, there is no operational/behavioural difference in the subjects of post-experiential revision depending on which method is used. Therefore, as a totalitarian government, you should select whichever method fits your time constraints, budget, and technological capabilities.
1: Internal methods (ie: neuroengineering) would be much more effective, but Dennett is concerned with convincing the reader that they can't trust their memory today.