Title: Secret Knowledge
Author: Hockney, David
Published by: Thames & Hudson
Year: 2006
First published: Thames & Hudson, 2001
Date reviewed: 4.08
ISBN: 978-0-500-28638-8

A book that’s as enjoyable to look at as it is fascinating to read. Hockney convincingly argues his case for the widespread use of optical aids by artists from the 15th century onwards.