Bob is blue. Bob is cold. Bob is nice. Bob is quiet. Bob is red. Bob is rough. Bob is smart. Dave is cold. Dave is nice. Dave is quiet. Dave is red. Dave is smart. If Dave is nice then Dave is rough. All smart things are rough. If something is cold then it is blue. Smart things are nice. If something is smart and cold then it is blue. If something is rough and blue then it is cold.
Bob is not blue.