Simon is a secondary character. He does not influence the story directly by his decision but is importent for the cohesion.
He stands up for Piggy and helps him get his glasses back when Jack knocks them off his head. This is his most importent behavior so far. As i mentioned one can recognize his moral abilitys and how he does not think in stereotypes as the other boys. He behaves equally friendly towards piggy and the smaller boys, as he does towards Jack and Ralph.
This shows, that his moral attidues are foundet on his believes and not on rules of society, Therfore he could represent the goodnes of mankind.
He does not seem to fear the situation but also does not underestimates the situation as far as we know. He is quit but not