From Archimedes' discovery of the principle of water displacement while taking a bath to Einstein's Theory of Relativity, from Brunelleschi's development of perspective drawing to the Impressionist revolution, from the taming of fire to the creation of the laser, "breakthrough thinking"—that is, a sudden, seemingly unaccountable moment of inspiration—has shaped and advanced civilization. But Nature invents, too—through evolutionary watersheds like vertebrate mammals and formerly grounded creatures making the leap to flight. How, then, does breakthrough thinking really work? What, if anything, does human invention have in common with biological evolution? Drawing on a rich knowledge of artificial intelligence and cognitive psychology, David Perkins offers a uniquely integrative theory of how breakthroughs occur, along with dozens of delightful mind puzzles and illustrations that will have you quizzing whomever happens to be nearest. B/W line drawings. Published in hardcover as Archimedes' Bathtub.