This book is dedicated to Caroline Grose.
Sincere thanks to Jill Grinberg and Anne Hoppe, twin champions of the meme. Also to the keen-eyed Eva Mills, Amanda Nettelbeck, Stella Paskins, Kristin Rens, Hilary Reynolds, and Sophie Splatt; expert advisers Katelyn Detweiler, Judy Downs, Ruth Estelle, Evan Goldfried, Justine Larbalestier, Nicholas Linke, Garth Nix, Sarah Shumway, Matthew Snyder, Laurel Symonds, Scott Westerfeld, and Sebastian Yeaman; Linda Shaw for vital physical maintenance; Sputnik for keeping the main thing the main thing; Douglas R. Hofstadter and Daniel C. Dennett for “the murdering Twinmaker”; and the (mis)quoted: Samuel Taylor Coleridge, Fyodor Dostoevsky, John Keats, Alfred Korzybski, François Duc de La Rochefoucauld, George W. Russell, William Shakespeare, Percy Bysshe Shelley, Theodore Sturgeon, and Oscar Wilde. Finally, to John Harwood, who reminded me that you don’t need to burn down the house to roast a pig.