Bob is big. Bob is red. Bob is rough. Charlie is quiet. Charlie is red. Charlie is smart. Charlie is white. Charlie is young. Dave is quiet. Dave is white. Gary is quiet. Gary is red. Smart, quiet people are young. Red people are quiet. If someone is young and quiet then they are red. White, quiet people are young. If Dave is young and Dave is red then Dave is smart. If Gary is young and Gary is quiet then Gary is white.
Dave is not smart.