"So the whole war is because we can't talk to each other."
"If the other fellow can't tell you his story, you can never be sure he isn't trying to kill you."
"What if we just left them alone?"
"Ender, we didn't go to them first, they came to us. If they were going to leave us alone, they could have done it a hundred years ago, before the First Invasion."
"Maybe they didn't know we were intelligent life. Maybe—"
This conversation occurs when Graff tells Ender his theory of why they are at war with the buggers. Graff tells Ender that since the buggers communicate through thought, they probably cannot understand that humans are thinking beings. Ender therefore wants to know why this cannot be remedied. Graff points out that they will never be sure the buggers will leave them alone and that they already attacked once. However, Ender still finds it hard to believe that intelligent life forms could be unwilling to have rational discussion. Ironically, Ender then goes on to destroy the buggers, colonize one of their worlds, find the queen pupa, and talk to it. He is the one who is able to communicate with the buggers, and it is this belief in the value of sentient beings talking through their problems that allows him to do so. Rather than destroying the bugger queen, he listens to what she tells him (through images in his mind) and decides that he can help her. The rest of humanity believes that the buggers are committed to warfare, but Ender will not give up on the notion of talking things over.