Two bacteria bump into each other in the stomach of a human being. “Gosh,” says one, “there are all sorts of weird things down here!” “Yup,” nods the other, “it’s like we found ourselves in a hectic chemistry lab rather than a tranquil human belly.” “Anyhow,” sighs the first bacterium, “we must search for the few things that are still worth our trouble in this belly.” “The way I see things,” the other one looks around and sighs, “our best bet is to go for the bacteria that remain alive and well in here, for they are bound to be in good enough shape to give us sustenance.” “But that would kill this poor human, and fast,” chuckles the first bacterium. “Hey,” chuckles the other in turn, “the way things look down here, this human is not far from breathing the last breath, anyhow.” The bacteria chuckle again and start looking for their own kind. “Bacteria,” they bellow mischievously, “here we come!”