Simon embodies and projects innocence. In Chapter 1, when he, Jack, and Ralph are feeling giddy about what a paradise the island is, Simon touches Ralph's arm "shyly." Any other boy might gently punch his arm in a friendly way to communicate the same thing. But Simon is more gentle.
Simon generous. He is the one who helps Ralph the most in building the shelters. In Chapter 4, Simon gives Piggy his share of the meat.
At the end of Chapter 8, Simon hallucinates or imagines that the beast (the "Lord of the Flies") is talking to him. It says "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 understands that this means the causes of fear and the potential for violence are not from the beast; rather, they come from the boys themselves. Simon understands that just as they are capable of goodness, they are also capable of destruction. Here, Golding presents Simon as something of a spiritual seer, one who understands the conflict between good and evil on a spiritual and psychological level.
The scene at the end of Chapter 3 shows Simon's peaceful, intuitive side. He goes off alone into the jungle and is at peace with nature. One can tell from this description that Simon is more interested in these kinds of peaceful excursions than he is about hunting or any activity that involves conflict or violence. The image of the dancing butterflies underscores this idea of Simon's peaceful nature:
He squatted down, parted the leaves and looked out into the clearing. Nothing moved but a pair of gaudy butterflies that danced round each other in the hot air. Holding his breath he cocked a critical ear at the sounds of the island.
"Simon" is also the name of the man who carried the cross for Jesus. Simon is commanded by Roman soldiers to help Jesus. He must bear the burden. This is symbolic because in Lord of the Flies, Simon bears the burden of building the shelters and more significantly, he is (in a sense) sacrificed when the boys kill him by mistake.