He always had a full potential for good, - to be loyal to Ralph and his idea of Rescue and civilisation - or to be evil - to be a compatriot of Jack's in his own land of savages, where the fist rules and reason doesn't exist. This is shown (as he threw stones to the sides of Henry) by the quote "Yet there was a space around Henry, perhaps six yards in diameter, into which he dare not throw. Here, invisible yet strong, was the taboo of the old life. Round the squatting child was the protection of parents and school and police-men and the law." (page 78)