William Golding's Lord of the Flies is on one level a novel about good versus evil. Golding uses Simon to convey his own ideas in several ways. First, Simon, like Piggy, is the voice of reason. He is rational, intelligent, and independent. He is the only one on the island who realizes the children need not fear a monster or beast; they must fear themselves. The beast lives inside of all of them. When the boys mistake the dead parachutist for the beast, Simon is the one who eventually discovers that there is no beast waving and flailing from the top of the mountain. However, before he is able to convince the boys that there is no beast, he is savagely beaten to death by the others. Obviously, Golding's hope for human nature must have been fairly low if Simon, a character who is beaten to death, was a representation of his ideas!
Golding intended and did present the nature of man and the destruction of civilization through his characters in the book "Lord of the Flies." Simon was used by Golding, to represent the spiritual side of man. He is the side of man that seeks answers. If you recall, Simon goes off to be alone and to think. Simon is also the one who goes to find the beast. Like Christ, Simon is also the one who is destroyed and is carried out by the water with a glow around him.
Golding needed a charcter that could represent the good and prutity of a person as well as to reflect the understanding of hmaity. Simon does this when he is talking with the hog's head and it tells him basically that the beast is in man. Golding used Simon in this manner to express his ideas.