I am extremely grateful to Alexandre Quintanilha and Jupp Korsten for reading the manuscript of this book and giving me their invaluable comments. Thanks, too, to Jacob Staub for his help with Hebrew and Aramaic, and an especially big hug for Jupp for his quick—and ever-cheerful—replies to all my questions about German. I’m also thankful to have had the encouragement of several German friends, especially Martina Hildebrandt, Wilhelm Schlenker, and Caroline Benzel.
I am greatly indebted to my editor, Becky Hardie, for her insightful comments and suggestions. Also thanks to Nick Robinson, Michael Rakusin, and all the good people at Constable & Robinson and Migdal Press.
In recent years, many excellent books have come out about the Nazi war on disabled people. I am particularly indebted to Henry Friedlander’s The Origins of the Nazi Genocide. Inge Deutschkron’s memoir, Outcast, was also of enormous help to me, and I thank her for it. As always, Gershom Scholem served as a guide—and an inspiration—for much that I’ve written here about kabbalah.