Dave is not quiet. Dave is not round. Erin is round. Erin is young. Harry is blue. Harry is not smart. Harry is young. If something is rough and nice then it is not blue. Blue things are quiet. If something is smart then it is rough. Blue, round things are not rough. If Dave is blue and Dave is round then Dave is smart. If something is not smart then it is young. If something is not smart and not round then it is rough. If something is not rough then it is not smart.
Dave is not smart.