"Cogito ergo sum." - Descartes

Here is a scenario: A human child has been raised by wolves since he was a baby. Is he a human or is he a wolf or is he something else?

What is identity? What makes us who we are? Do our physical traits determine our identity, or our minds? How do we derive our identities? If we cannot find our identity from externalities, can we know ourselves - are our identities unknown to us?