Instruct: Classify a given review as either positive or negative.
Query: Birth of a Nation (1915)

This film truly demonstrates Griffith's genius as a director, producer and editor. He manages to tell an epic of a story with bold camera work, clever cuts and balanced pacing. He includes historical interpretation, adventure and romance. It's unfortunate that he possessed such a twisted morality. The first half, which concerns the civil war, is very watchable, but second part portrays blacks as either ignorant or evil (mostly played by whites in blackface) and features the Klu Klux Klan as righteous heroes.