French military surgeon Jules Cotard lived only 49 years (1840-1889), but he will be forever remembered for discovering one of nature's most sincerely fucked-up mental illnesses: Cotard's syndrome is a mental disorder where the victim concludes that he or she is dead. Sometimes the symptoms are more specific: Patients believe that they are missing certain internal organs, or that there is no blood in their veins, or that they have lost their soul. However, the ultimate manifestation of Cotard's syndrome (classified medically as a nihilistic delusional disorder) is the victim's unshakable conviction that he or she does not exist. It is not that these people fear they are dying; it's that they are certain they are already dead.
Sometimes the victims of Cotard's syndrome think they can smell their own flesh rotting.
- from Killing Yourself to Live by Chuck Klosterman