This book is never going to be in the same sales league as Harry Potter and the author is entitled to charge a fair price for his work- this book isn't something that's taken him a few rainy weekends to write in his spare time. The more specialised a subject and smaller the niche- the higher the cost.

Though Stephen Hawkin's managed to sell his Brief History Of Time to a mass audience- and that wasn't exactly light reading. One of the few books that made me think I really should have paid more attention in school!