In chapter 4 of "Lord of the Flies", when Ralph is mad at Jack for letting the fire go out, Simon says that he is afraid. Why is he afraid?

does not say that he is
afraid, the narration says that he "...looked now, fromto , ..., and what he say made him
afraid."  Simon is the first one in the story to realize that the biggest fear the boys
have is of their inner savagery.  He realizes it is no outside beast who will bring them down;
it is themselves that will bring them down.  He sees the anger on Ralph's face and the brutality
on Jack's painted face.  He seems to sense that these two boys represent the opposing forces on
the island and that the brutal, savage force (Jack) will win.  Jack has painted his face for the
first time, giving him a mask to hide behind as much as a mask to hide him from the pig. Simon
has a good sense of right and justice, which is why he gives his portion of meat toat the end of
the chapter.  This sense of right tells him that Ralph is right regarding the need for fire, but
it also tells him that the boys are beginning to fall apart; that the savage force is beginning
to take over.  He especially sees that in Jack, though he also understands the need for food
that Jack provides.