Simon represents an innate goodness, and his actions are consistently benevolent. He does not participate in the bloodthirsty hunts which drive Jack's group. He takes care of the needs of the youngest kids, giving the "choicest" fruit to them and comforting them at night. When the rest of the group is terrified of the "beast" on the island, it is Simon who points out that "maybe it's only us," demonstrating his knowledge of the evil tendencies that reside within all of mankind. As the other boys shed the conditioning of society, becoming increasingly savage the longer they remain on the island, Simon becomes more reflective, spending time alone and in the midst of nature. Despite his integrity, the rest of the group murders Simon, which demonstrates the overpowering abilities of evil when goodness is scarce.
Simon's death is also a turning point in the characterization of Piggy and Ralph. Until this point, they have removed themselves from the hunters' plans, standing as a sort of antithesis to Jack's savagery. Yet it is important to note that in this scene, Piggy and Ralph participate, albeit indirectly, in Simon's murder. As Simon stumbles out of the forest, Piggy and Ralph are as equally blinded as the rest of the group to the truth, recognizing Simon as a "beast" and doing nothing to save him. They regret this later, but in that moment, they prove to be as savage as the rest of the boys, which demonstrates the power of a mob-like group mentality.