an annoying person addicted to and obsessed by a single theory, for which they have no evidence and to which they stick despite all evidence to the contrary.
See: RavingAtheists forum for hundreds of similar- if not identical posts:
Calpurnpiso says:"This is exactly my point. Religious-psychosis attacks brains susceptible to this form of schizophrenia mixed with temporal lobe epilepsy disease. This is my hypothesis since the cause of about 90% of neurologiocal disorders, including schizophrenia, TLE is unknown. If the cause of schizophrenia or TLE was known I would not be so certain religious DELUSIONAL BELIEFS, which are not unlike those produced by the schizophrenic, TLE, Drugged, Traumatized brain, are a form of mental illness!.
The brain is an organ like any other organs of the body, and they ALL are susceptible to illness some genetic and some acquired. Aren't some people born with underdeveloped optic nerve? Though having normal vision the brain can't interpret them correctly. Only over 50 years ago, these people would be labeled mentally retarded!"