Dave is green. Dave is rough. Fiona is furry. Fiona is quiet. Fiona is not rough. Fiona is smart. Fiona is white. White things are blue. All green things are white. If something is quiet and rough then it is white. If something is not quiet then it is furry. All quiet things are white. If something is smart then it is furry. If something is rough and blue then it is smart. If something is not white and not furry then it is not green.
Fiona is blue.