Instruct: Classify Amazon reviews into positive or negative sentiment
Query: good idea, but thats about it

I have enjoyed Clarke at times. 'City and the Stars,' or Rendezvous with Rama.' This idea here is a great one, looking back in time with the use of a worm hole. I also like his further exploration of ideas explored in 'Childhoods End.' What you have here is one of the two most important aspects of Science Fiction portrayed in all of its magnificence. A good idea to wrap the story around. But the characters or the means these two authors use to get the idea across feels academic. Because of the stiffness and secondary nature of the story, it is almost unreadable.If you want a good story, skip this book. If you are looking for a great science fiction idea, this is a five star read.