Sybil is unable to see anything beyond what he wants to see. He sees ghosts in every corner, like Trump, he believes he's the smartest guy in every room. He truly believes he can easily fool people with his socks which are, in reality, such strong different facets of his personality that, IMO, he's crossed over into schizophrenia.
We all have a little bit of everything in the DSM-V inside us. For some it's a flicker, for others it's their entire lives. The interest for me is observing who is inside the normal parameters, on average, and who isn't. Sybil isn't.