"I met him once, in Amazonia. Pellinore was off on another one of his quixotic quests, I believe for a specimen of that elusive—mythical, in my opinion—parasitic organism known as Biminius arawakus. Your father was quite ill, as I recall—malaria, I think, or some other bloody tropical disease. We do work ourselves into a tizzy about creatures like the Anthropophagi, but the world is chock-full of things that want to eat us. Have you ever heard of the candiru? It's also a native of the Amazon and, unlike the Biminius arawakus, not too difficult to find, particularly if you are unfortunate or stupid enough to relieve yourself anywhere near where one is hiding. It's a tiny eel-like fish, with backward-pointing razor-sharp spines along its gills that it unfurls like an umbrella once inside its host. Usually it follows the scent of urine into the urethra, wherein it lodges itself to feed upon your innards, but there have been cases where it enters the anus instead and commences to eat its way through your large intestine. It grows larger and larger as it feeds, of course, and I hear the pain is beyond the power of words to describe. So excruciating, in fact, that the common native remedy is to simply chop off the penis. What do you think of that?" he concluded with a wide smile.
"What do I think, sir?" I quavered.
"Yes, what do you think? What do you make of it? Or of the Spirometra mansoni, commonly called a flatworm, which can grow up to fourteen inches long and take up residence in your brain, where it feeds upon your cerebral matter until you are reduced to a vegetative state? Or Wuchereria bancrofti, a parasite that invades the lymph nodes, often causing their male hosts to develop testicles the size of cannonballs. What are we to make of them, Will Henry, and the multitudinous others? What lesson is to be gained?"
"I—I . . . I really don't know, sir."
"Humility, Will Henry! We are a mere part of a grand whole, in no way superior, not at all the angels in mortal attire we pretend to be. I do not think that the candiru gives a tinker's damn that we produced a Shakespeare or built the pyramids. I think we just taste good." (10.221-225)
Here we have the lesson Yancey is trying to impart on us, the horrified readers, point blank: We need to gain humility from our role in the natural cycle and stop believing that everything revolves around us. Like cancer, these parasites aren't killing us out of some evil design; we are just its food source. It's not a pleasant lesson to learn, but one we could all benefit from in the long run.