In Lord of the Flies, what does Simon mean when he says,"What I mean is...maybe its only us...We could be sort of...?"

In "Lord of The Flies," the boys are at yet another group meeting and Ralph is trying to get across the importance of following through with their plans.  The group begins talking about the "monsters" they have heard or seen on the island.  The "littluns" are particularly frightened and Ralph is trying to reassure them there are not monsters while still letting them express themselves.  Simon raises the point that ,"What I mean is...maybe its only us...We could be sort of..." 

Simon is trying to tell the boys that the "monster" is within them.  He is wanting the group to see that they are creating these ideas because the true fear, the true monster is in each of us.  He stutters and stops because he knows that they won't understand and he fears he can't state it correctly or clearly enough to make everyone understand.  They will just think he is crazy.