Sontag, a cancer survivor at the time, wrote Illness as a Metaphor to explore and elucidate the metaphors used to describe serious illnesses like cancer and tuberculosis. Sontag argues that the metaphors and mythology created around these diseases make them seem evil and mysterious and very much like invincible predators, and hence sometimes prevent people from believing in conventional treatment to cure them. In addition, since cancer is seen as obscene, repugnant to the senses, and ill-omened, the person suffering from it is seen as morally, if not literally, contagious. Cancer occupies the spot reserved for TB in the past as a shameful disease meaning imminent death, but unlike TB, which was seen as a more ethereal, and metaphorically, a disease of the soul, cancer is definitely a disease of the body, and many times of its more shameful parts like colon or rectum. Both TB and cancer have been seen as diseases of passion- TB as a result of too much of it, and cancer as a result of too little.
Sontag argues that patients are hardly helped by seeing and hearing all possible evils compared to cancer, and hopes that with advances in the treatment of cancer the metaphors will become obsolete.
An interesting book, and since written before the times of AIDS very true about the place cancer and TB have been occupying in our mythology. Maybe a bit too repetitious. I did not realize how many famous people suffered from and died of tuberculosis.