Hokas, I addressed the philosophical question of identity. This question has arisen again while reading SM Stirling's Draka series.
Marya, the serf who is also an OSS agent, reflects that her non-stop performance as a serf is like method acting:
"...creating and living in a persona. She suspected most born-serfs did the same from infancy, less consciously; it was impossible to tell how many retained anything beneath the role, how many became it."
-SM Stirling, The Stone Dogs (New York, 1990), p. 397.
But surely we all live a persona or role from infancy and usually also become it? Any two babies could have been switched at birth. Thus, a man who has been a Christian all his life would instead have been a Hindu all his life, and vice versa. We accept these arbitrarily assigned roles and mistakenly believe that they are actually substantial identities whereas the only reality is that we are malleable social organisms sharing one planet where the borders exist only in our minds - as do many other social conventions, most significantly money.
In Britain, some undercover cops infiltrated the movements (animal rights, environmentalism, Justice for Stephen Lawrence etc). In some cases, the undercover men entered into relationships with female campaigners who then had children by them. When it was revealed that some such undercover police officers had been agent provocateurs, convictions had to be quashed. These men must have been doing what Marya calls "method acting" and might subsequently have encountered difficulty in differentiating between their two identities.