Reviews of "Unknown Quantity"

Date of review	Periodical	Reviewer	Representative quote
July 2007	Literary Review	Alexander Masters	"John Derbyshire's Unknown Quantity is everything a popular mathematics book should be: gentle, chatty, anecdotal and full of mind-aching equations."
May 12, 2007	The Economist	<No byline>	"His book is a demanding read, with its fair share of mathematical diagrams and equations, but the fascination of the subject does come across."
Feb. 13, 2006	Publishers Weekly	<No byline>	"Derbyshire offers a very real and very entertaining survey of the development of algebra"
May 2006	Focus	Luiz Henrique de Figueiredo	"In summary, I think Derbyshire has done at good job at portraying algebra and its journey toward abstraction from its roots in early civilizations. All interested readers will learn something about mathematics and its history."
May 15, 2006	Library Journal	Ian Gordon	"[Derbyshire] interweaves historical insight and biographical sketches into a book that is both compelling and easy to follow."
June 2006	New English Review	Rebecca Bynum	"Mr. Derbyshire one of those very rare writers who seems to be continually conscious of how his words will be received by the reader. He is respectful without being presumptuous and so provides the necessary background for people like myself who have very little mathematical experience. I found I could easily follow the main action in the book, which is rightly centered on abstract mathematics, but that the story did not require my complete comprehension of all the details in every equation: a big plus for anyone who might normally be intimidated by a book like this."
June 9, 2006	Science	Victor Katz	"In general, the book succeeds in its aim of enlightening the non-expert on what algebra is today, giving good summaries of recent work in such fields as algebraic topology, algebraic geometry, and even category theory. Unfortunately, Derbyshire's history of algebra through the 17th century has many shortcomings."
June 24, 2006	New Scientist	Ben Longstaff	"A first-rate account that even algebraphobes will struggle to fault."
July 18, 2006	VDARE	Wolfgang Zernik	"Look, let's be frank, the eyes may tend to glaze over. The successful author has to find a way to deal with this problem. Derbyshire does deal with it and as readers of Prime Obsession will remember he does so by telling lots of entertaining personal stories."
August 28, 2006	National Review	Michael Westmoreland	"With this new book, Derbyshire establishes himself as one of our foremost expositors of mathematics."