Who do you think you are?

Paul Joseph Fronczak's story, as told to the BBC and in the book The Foundling, is an incredible one - not least because it wasn't until the age of 51 that he found out that Paul Joseph Fronczak wasn't his real name. A sense of self-identity is so fundamental to us - sometimes the only thing that seems certain - that it's almost impossible to imagine how difficult it must have been to comprehend and cope with what he discovered.