Bob is furry. Bob is green. Bob is quiet. Bob is not round. Bob is white. Bob is young. Dave is blue. Dave is furry. Dave is green. Dave is young. Harry is blue. Harry is green. If Dave is quiet then Dave is white. If someone is quiet and not young then they are blue. All round, green people are white. Green people are quiet. If Dave is round and Dave is furry then Dave is quiet. If Dave is green and Dave is not quiet then Dave is blue.
Dave is quiet.