Books and magazines often provide secondary, not primary, information. Top: Book-cover from the book Through the Language Glass: Why the World Looks Different In Other Languages by Guy Deutscher. Book-cover design by Steve Attardo and Rodrigo Corral. Book-cover design copyright © 2011 by Steve Attardo and Rodrigo Corral. Used by permission of Henry Holt and Company, LLC. All rights reserved. Bottom: Reprinted by permission from Macmillan Publishers Ltd: Nature, copyright © 2008.