You are what you eat. Clothes make the man. We've plenty of ways of slightly modifying our identity, some more drastic than others.

Socialite Tara-Palmer Tomkinson has said she "feels like a different person" after getting a new nose. The victim of a gruesome penis-hacking incident may feel the same.

Would they be right to think so? At what point can you change and remain the same person – and should you? Do you belong to the Billy Joel school of thought – Don't go changing, to try and please me – or, like David Bowie, conclude Just gonna have to be a different man?

Is your identity something essential or forever in flux – what makes you, you?