Psychology? It's all in the mind.
Mental disorder characterized by delusions of persecution or grandeur, usually without hallucinations. Paranoia was formerly classified as a distinct psychosis but is now generally treated as one of several varieties of schizophrenia or, in milder cases, of personality disorder. The paranoid person generally suffers from exaggerated self-reference, a tendency to construe independent events and acts as pertaining to him- or herself.
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