Psychosis:

Psychosis is a loss of contact with reality that usually includes:

    *  False beliefs about what is taking place or who one is (delusions)

    *  Seeing or hearing things that aren't there (hallucinations)

For me a whole bunch of stuff became clear when I stopped assuming rationality and demanded proof.

She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre