Dave is cold. Erin is furry. Erin is nice. Erin is rough. Fiona is blue. Fiona is cold. Fiona is furry. Fiona is rough. Fiona is round. Fiona is smart. All cold things are rough. Furry, nice things are rough. If Dave is rough and Dave is round then Dave is nice. If Erin is nice then Erin is rough. If Fiona is rough then Fiona is nice. If something is cold and furry then it is smart. If Erin is smart then Erin is round. If something is blue then it is cold.
Dave is not nice.