During his imagined conversation with The Lord of the Flies, Beelzebub, Simon has a spiritual realization: the beast is within everyone.
After having said "What else is there to do?" when the others have despaired of dealing with what they believe to be the beast, Simon leaves the other boys and climbs upward again; he goes to the clearing where he can be alone and rest. Without Simon's knowing, however, Jack and Roger and the others have killed a sow, cut off her head, and left it on a stake in this same area as an offering to the beast. Now, in an exhausted trance, Simon stares at this bleeding head:
The half-shut eyes were dim with the infinite cynicism of adult life. They assured Simon that everything was a bad business.
Simon hears himself say, "I know that." Then, he tries to convince himself that he is merely creating voices in his head: "Pig's head on a stick" he says aloud. But, Simon thinks he hears ridiculing laughter and the Lord of the Flies saying,
"Fancy thinking the Beast was something you could hunt....You knew, didn't you? I'm part of you? Close, close, close! I'm the reason why it's no go? Why things are what they are?"
Simon finds himself looking into a "vast mouth." He has a seizure and passes out as, horrified, he realizes that the beast they all have been searching for is within themselves.