The two-headed woman and her six-legged dog waited with an empty vegetable basket by the new gate; the woman crooned softly to the dog. Four of the dog’s legs were healthy legs, but an extra pair dangled uselessly at its sides. As for the woman, one head was as useless as the extra legs of the dog. It was a small head, a cherubic head, but it never opened its eyes. It gave no evidence of sharing in her breathing or her understanding. It lolled uselessly on one shoulder, blind, deaf, mute, and only vegetatively alive. Perhaps it lacked a brain, for it showed no sign of independent consciousness or personality. Her other face had aged, grown wrinkled, but the superfluous head retained the features of infancy, although it had been toughened by the gritty wind and darkened by the desert sun.

Walter M. Miller, Jr., A Canticle for Leibowitz (271)