Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.

Let me give you an example: I've read this book with much expectation, it was very boring all through out the book
The answer to this example can be: Negative
Here is why: Review writer does not like the book because it was boring, therefore it is a negative review.

OK. solve this:
I read this novel as a trilogy of Prelude to Foundation, Foundation and Second Foundation. The story of the last years of the Trantor Empire helped me understand a lot about our society. Even though I read it in College I still have Harry Seldon name stock in my mind. Isaac uses this story to present his theories on how science and religion influence our society. It is a marvelous saga of a loooong story of a new Empire (USA?) build after the fall of an old one (Britain?). More or less this will be a very entertaining textbook on social science of history. A must for a serious SCFI reader.
Answer:
Positive