Anne is blue. Anne is green. Anne is rough. Anne is round. Dave is blue. Dave is rough. Dave is young. Gary is quiet. Gary is rough. Gary is white. Harry is blue. Harry is white. If someone is rough and blue then they are white. If Gary is young then Gary is green. All white, rough people are green. If someone is green and rough then they are blue. All green people are rough. White, quiet people are young.
Dave is not white.