Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: I do not understand this one

I am a HUGE fan of Heinlein and currently in the middle of re-reading his entire collection of writing. I absolutely love most of his works, but I just do not get this one. I find it bizzare, convolutted and twisted. It took me a month to go through it and looking back, I probably should have stopped reading at page 15 or so. I am very disappointed by this book.