
by David Kahn
Rating: 4.2 ⭐
• 2 recommendations ❤️
The magnificent, unrivaled history of codes and ciphers—how they're made, how they're broken, and the many and fascinating roles they've played since the dawn of civilization in war, business, diplomacy, and espionage—updated with a new chapter on computer cryptography and the Ultra secret.Man has created codes to keep secrets and has broken codes to learn those secrets since the time of the Pharaohs. For 4,000 years, fierce battles have been waged between codemakers and codebreakers, and the story of these battles is civilization's secret history, the hidden account of how wars were won and lost, diplomatic intrigues foiled, business secrets stolen, governments ruined, computers hacked. From the XYZ Affair to the Dreyfus Affair, from the Gallic War to the Persian Gulf, from Druidic runes and the kaballah to outer space, from the Zimmermann telegram to Enigma to the Manhattan Project, codebreaking has shaped the course of human events to an extent beyond any easy reckoning. Once a government monopoly, cryptology today touches everybody. It secures the Internet, keeps e-mail private, maintains the integrity of cash machine transactions, and scrambles TV signals on unpaid-for channels. David Kahn's The Codebreakers takes the measure of what codes and codebreaking have meant in human history in a single comprehensive account, astonishing in its scope and enthralling in its execution. Hailed upon first publication as a book likely to become the definitive work of its kind, The Codebreakers has more than lived up to that it remains unsurpassed. With a brilliant new chapter that makes use of previously classified documents to bring the book thoroughly up to date, and to explore the myriad ways computer codes and their hackers are changing all of our lives, The Codebreakers is the skeleton key to a thousand thrilling true stories of intrigue, mystery, and adventure. It is a masterpiece of the historian's art.
by Leo Marks
Rating: 4.2 ⭐
• 2 recommendations ❤️
In 1942, Leo Marks left his father's famous bookshop, 84 Charing Cross Road, and went off to fight the war. He was twenty-two. Soon recognized as a cryptographer of genius, he became head of communications at the Special Operations Executive (SOE), where he revolutionized the codemaking techniques of the Allies and trained some of the most famous agents dropped into occupied Europe, including "the White Rabbit" and Violette Szabo. As a top codemaker, Marks had a unique perspective on one of the most fascinating and, until now, little-known aspects of the Second World War.Writing with the narrative flair and vivid characterization of his famous screenplays, Marks gives free rein to his keen sense of the absurd and his wry wit, resulting in a thrilling and poignant memoir that celebrates individual courage and endeavor, without losing sight of the human cost and horror of war.
Challenging the Conventional Wisdom on Diet, Weight, and DiseaseIn this groundbreaking book, the result of seven years of research in every science connected with the impact of nutrition on health, award-winning science writer Gary Taubes shows us that almost everything we believe about the nature of a healthy diet is wrong.For decades we have been taught that fat is bad for us, carbohydrates better, and that the key to a healthy weight is eating less and exercising more. Yet with more and more people acting on this advice, we have seen unprecedented epidemics of obesity and diabetes. Taubes argues persuasively that the problem lies in refined carbohydrates (white flour, sugar, easily digested starches) and sugars–via their dramatic and longterm effects on insulin, the hormone that regulates fat accumulation–and that the key to good health is the kind of calories we take in, not the number. There are good calories, and bad ones.Good CaloriesThese are from foods without easily digestible carbohydrates and sugars. These foods can be eaten without restraint.Meat, fish, fowl, cheese, eggs, butter, and non-starchy vegetables. Bad CaloriesThese are from foods that stimulate excessive insulin secretion and so make us fat and increase our risk of chronic disease—all refined and easily digestible carbohydrates and sugars. The key is not how much vitamins and minerals they contain, but how quickly they are digested. (So apple juice or even green vegetable juices are not necessarily any healthier than soda.) Bread and other baked goods, potatoes, yams, rice, pasta, cereal grains, corn, sugar (sucrose and high fructose corn syrup), ice cream, candy, soft drinks, fruit juices, bananas and other tropical fruits, and beer. Taubes traces how the common assumption that carbohydrates are fattening was abandoned in the 1960s when fat and cholesterol were blamed for heart disease and then –wrongly–were seen as the causes of a host of other maladies, including cancer. He shows us how these unproven hypotheses were emphatically embraced by authorities in nutrition, public health, and clinical medicine, in spite of how well-conceived clinical trials have consistently refuted them. He also documents the dietary trials of carbohydrate-restriction, which consistently show that the fewer carbohydrates we consume, the leaner we will be. With precise references to the most significant existing clinical studies, he convinces us that there is no compelling scientific evidence demonstrating that saturated fat and cholesterol cause heart disease, that salt causes high blood pressure, and that fiber is a necessary part of a healthy diet. Based on the evidence that does exist, he leads us to conclude that the only healthy way to lose weight and remain lean is to eat fewer carbohydrates or to change the type of the carbohydrates we do eat, and, for some of us, perhaps to eat virtually none at all.The 11 Critical Conclusions of Good Calories, Bad Calories: 1. Dietary fat, whether saturated or not, does not cause heart disease. 2. Carbohydrates do, because of their effect on the hormone insulin. The more easily-digestible and refined the carbohydrates and the more fructose they contain, the greater the effect on our health, weight, and well-being. 3. Sugars—sucrose (table sugar) and high fructose corn syrup specifically—are particularly harmful. The glucose in these sugars raises insulin levels; the fructose they contain overloads the liver.4. Refined carbohydrates, starches, and sugars are also the most likely dietary causes of cancer, Alzheimer’s Disease, and the other common chronic diseases of modern times. 5. Obesity is a disorder of excess fat accumulation, not overeating and not sedentary behavior. 6. Consuming excess calories does not cause us to grow fatter any more than it causes a child to grow taller. 7. Exercise does not make us lose excess fat; it makes us hungry. 8. We get fat because of an imbalance—a disequilibrium—in the hormonal regulation of fat tissue and fat metabolism. More fat is stored in the fat tissue than is mobilized and used for fuel. We become leaner when the hormonal regulation of the fat tissue reverses this imbalance. 9. Insulin is the primary regulator of fat storage. When insulin levels are elevated, we stockpile calories as fat. When insulin levels fall, we release fat from our fat tissue and burn it for fuel. 10. By stimulating insulin secretion, carbohydrates make us fat and ultimately cause obesity. By driving fat accumulation, carbohydrates also increase hunger and decrease the amount of energy we expend in metabolism and physical activity.11. The fewer carbohydrates we eat, the leaner we will be. Good Calories, Bad Calories is a tour de force of scientific...