Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Pure Science Fiction

Far above his Mission Earth Series, Battlefield Earth is one heck of a good book. Despite its length, I can usually finish it in three days or less. It's that riveting.Jonny versus the Psychlos.Humans are no longer the dominant species on Earth. As a lark, one psychlo takes a human, Jonny, and teaches him quickly through technology.One thing leads to another and Jonny begins teaching other humans, they learn of their past, and set about expelling the Psyclos from Earth.Full of action, and rags to riches. Enough to satisfy anyone.