When Nick Inman's bank asked him to identify himself he realized he had an interesting problem. Who was he really? How did he know who he was? And how on earth could he prove it beyond doubt that the person inside his head was the same as the person outside, as detailed on his documentation?

Moving like a detective story, this book pieces together the formula or recipe for a complete human being, listing ingredients from the prosaic to the surprising.

Self-knowledge - even merely posing questions about our true nature - is an essential part of personal growth; but its more important than that. All knowledge depends on it: how can we know anything if we don't know who is asking the questions and giving sense to reality? Can we be truly virtuous and empathetic if we don't know where these feelings stem from?

En route to its destination, the book addresses some intriguing conundrums. Can science offer a complete description of an individual; without accepting the existence of mind, consciousness and spirit? Are we in danger of losing ourselves as we are taken over by our virtual identities? How does suffering shape us and equip us to help others to heal? Is technology (biometrics) the best way to decide between friend and foe? And what will be the future for the human soul when we allow machines to become "people" too?