Project Hail Mary

by Andy Weir

“Humans are very different,” I say. “We get diseases all the time. We have very powerful immune systems. Also, we find cures for diseases in nature. The word is ‘antibiotics.’” “No understand,” he says. “Cures for diseases in nature, question? How, question?” “Other life on Earth evolved defenses against the same diseases. They emit chemicals that kill the disease without harming other cells. Humans eat those chemicals and they kill disease but not our human cells.” “Amaze. Erid no have this.” “It’s not a perfect system, though,” I say. “Antibiotics work very well at first, but then over the years, they become less and less effective. Eventually they barely work at all.” “Why, question?” “Diseases change. Antibiotics kill almost all the disease in the body, but some survive. By using antibiotics, humans are accidentally teaching diseases how to survive those antibiotics.”