The Codebreakers Quotes

“The multiple human needs and desires that demand privacy among two or more people in the midst of social life must inevitably lead to cryptology wherever men thrive and wherever they write. Cultural diffusion seems a less likely explanation for its occurrence in so many areas, many of them distant and isolated.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“the use of atbash in the Bible sensitized the monks and scribes of the Middle Ages to the idea of letter substitution. And from them flowed the modern use of ciphers—as distinct from codes—as a means of secret communication.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Much of the history of cryptology of this time is a patchwork, a crazy quilt of unrelated items, sprouting, flourishing, withering. Only toward the Western Renaissance does the accreting knowledge begin to build up a momentum. The story of cryptology during these years is, in other words, exactly the story of mankind.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Every weapon of cryptanalytic science—which in the stratospheric realm of this solution drew heavily upon mathematics, using group theory, congruences, Poisson distributions—was thrown into the fray.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Analyzing the frequency and contacts of letters is the most universal, most basic of cryptanalytic procedures.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“The technique was at least moderately well known, for Ibn Khaldūn wrote in The Muqaddimah: “Occasionally, skillful secretaries, though not the first to invent a code [and with no previous knowledge of it], nonetheless find rules [for solving it] through combinations which they evolve for the purpose with the help of their intelligence, and which they call ‘solving the puzzle [cryptanalysis].”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Also of great importance in the discovery of linguistic phenomena that led to cryptanalysis was the development of lexicography.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“This list encompassed, for the first time in cryptography, both transposition and substitution systems, and, moreover, gave, in system 5, the first cipher ever to provide more than one substitute for a plaintext letter. Remarkable and important as this is, however, it is overshadowed by what follows—the first exposition on cryptanalysis in history.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Ibn ad-Duraihim, according to Qalqashandi, gave seven systems of cipher:”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“The Arabic knowledge of cryptography was fully set forth in the section on cryptology in the Subh al-a ‘sha, an enormous, 14-volume encyclopedia”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Extremist sects in Islam cultivated cryptography to conceal their writings from the orthodox.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Cryptology was born among the Arabs. They were the first to discover and write down the methods of cryptanalysis. The people that exploded out of Arabia in the 600s and flamed over vast areas of the known world swiftly engendered one of the highest civilizations that history had yet seen. Science flowered. Arab medicine and mathematics became the best in the world—from the latter, in fact, comes the word “cipher.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“But of any science of cryptanalysis, there was nothing. Only cryptography existed. And therefore cryptology, which involves both cryptography and cryptanalysis, had not yet come into being so far”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“All this stained cryptology so deeply with the dark hues of esoterism that some of them still persist, noticeably coloring the public image of cryptology. People still think cryptanalysis mysterious. Book dealers still list cryptology under “occult.” And in 1940 the United States conferred upon its Japanese diplomatic cryptanalyses the codename MAGIC.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“cryptology is black magic in itself springs ultimately from a superficial resemblance between cryptology and divination. Extracting an intelligible message from ciphertext seemed to be exactly the same thing as obtaining knowledge by examining the flight of birds, the location of stars and planets, the length and intersections of lines in the hand, the entrails of sheep, the position of dregs in a teacup. In all of these, the wizardlike operator draws sense from grotesque, unfamiliar, and apparently meaningless signs. He makes known the unknown.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“The association of magic and cryptology was reinforced by other factors. Mysterious symbols were used in such esoteric fields as astrology and alchemy—where each planet and chemical had a special sign, like the circle and arrow for Mars—just as they were in cryptology. Like words in cipher, spells and incantations, such as “abracadabra,” looked like nonsense but in reality were potent with hidden meanings.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Cryptology served magical purposes frequently throughout the Middle Ages, and even in the Renaissance was still disguising important parts of alchemical formulas.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“From the early days of its existence, cryptology had served to obscure critical portions of writings dealing with the potent subject of magic—divinations, spells, curses, whatever conferred supernatural powers on its sorcerers. The first faint traces of this appeared in Egyptian cryptography. Plutarch reported that “sundry very ancient oracles were kept in secret writings by the priests” at Delphi. And before the fall of the Roman empire, secret writing was serving as a powerful ally of the necromancers in guarding their art from the profane. One of the most famous magic manuscripts, the so-called Leiden papyrus, discovered at Thebes and written in the third century A.D. in both Greek and a very late form of demotic, a highly simplified version of hieroglyphics, employs cipher to conceal the crucial portions of important recipes.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“the conviction in the minds of many people that cryptology is a black art, a form of occultism whose practitioner must, in William F. Friedman’s apt phrase, “perforce commune daily with dark spirits to accomplish his feats of mental jiu-jitsu.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“the most famous of all those who had an acquaintance with cryptology in the Middle Ages was an English customs official, amateur astronomer, and literary genius named Geoffrey Chaucer.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“The only writer of the Middle Ages to describe cryptography instead of just using it was Roger Bacon, the English monk of startlingly modern speculations. In his Epistle on the Secret Works of Art and the Nullity of Magic, written about the middle of the 1200s,”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Hildegard von Bingen, an 11th-century nun who saw apocalyptic visions and was later canonized, had a cipher alphabet which she claimed came to her in a flash of inspiration.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Tradition attributes to St. Boniface, the Anglo-Saxon missionary who founded monasteries in Germany in the eighth century, the importation to the continent of cryptographic puzzles based on a dots-for-vowels system.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“For almost a thousand years, from before 500 to 1400, the cryptology of Western civilization stagnated.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“soon as a culture has reached a certain level, probably measured largely by its literacy, cryptography appears spontaneously—as”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Suetonius, the gossip columnist of ancient Rome, says that Caesar wrote to Cicero and other friends in a cipher in which the plaintext letters were replaced by letters standing three places further down the alphabet, D for a, E for b, etc.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Polybius, devised a system of signaling that has been adopted very widely as a cryptographic method. He arranged the letters in a square and numbered the rows and columns. To use the English alphabet, and merging i and j in a single cell to fit the alphabet into a 5 × 5 square: Each letter may now be represented by two numbers—that of its row and that of its column. Thus e = 15, v = 51. Polybius suggested that these numbers be transmitted by means of torches—one torch in the right hand and five in the left standing for e, for example. This method could signal messages over long distances. But modern cryptographers have found several characteristics of the Polybius square, or “checkerboard,” as it is now commonly called, exceedingly valuable—namely, the conversion of letters to numbers, the reduction in the number of different characters, and the division of a unit into two separately manipulable parts. Polybius’ checkerboard has therefore become very widely used as the basis of a number of systems of encipherment.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“Another steganographic system was still in use in the 20th century: Aeneas suggested pricking holes in a book or other document above or below the letters of the secret message. German spies used this very system in World War I, and used it with a slight modification in World War II—dotting the letters of newspapers with invisible ink.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“The world owes its first instructional text on communications security to the Greeks. It appeared as an entire chapter in one of the earliest works on military science, On the Defense of Fortified Places, by Aeneas the Tactician.”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet

“they employed a device called the “skytale,” the earliest apparatus used in crypto-logy”
― David Kahn, The Codebreakers: The Comprehensive History of Secret Communication from Ancient Times to the Internet