Instruct: Classify Amazon reviews into positive or negative sentiment
Query: the best sci fi concept ever!

OK , let me give it to you plain and simple.This is the best science fiction concept EVER!!! But wait, there's more! This book trancends the label of " science fiction". It is also part biography , part history novel, part adventure, part damn good read!Critics of the book mainly get all caught up in the fact that the writing is perhaps not as brilliant in a literary way as the great authors. But you need to give Farmer a bit of leeway here.The great authors could never have come up with a concept like this, and sustain the excitement throughout the novel. It is also very well researched and he brings characters like Sir Richard Francis Burton and Alice Hargreaves back to life. The concept is also so incredibly grand and breathtaking, that it would really take 20 books to do it justice, so Farmer is doing the best he can in one short book, and the trade off is that the pace just keeps you on the edge of your seat.Do yourself a favour and read this book!!!