Quotes from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“The first known European book to describe the use of cryptography was written in the thirteenth century by the English Franciscan monk and polymath Roger Bacon. Epistle on the Secret Works of Art and the Nullity of Magic included seven methods for keeping messages secret, and cautioned: “A man is crazy who writes a secret in any other way than one which will conceal it from the vulgar.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“if N is large enough, it is virtually impossible to deduce p and q from N, and this is perhaps the most beautiful and elegant aspect of the RSA asymmetric cipher.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Ron Rivest, one of the inventors of RSA, thinks that restricting cryptography would be foolhardy: It is poor policy to clamp down indiscriminately on a technology just because some criminals might be able to use it to their advantage. For example, any U.S. citizen can freely buy a pair of gloves, even though a burglar might use them to ransack a house without leaving fingerprints. Cryptography is a data-protection technology, just as gloves are a hand-protection technology. Cryptography protects data from hackers, corporate spies, and con artists, whereas gloves protect hands from cuts, scrapes, heat, cold, and infection. The former can frustrate FBI wiretapping, and the latter can thwart FBI fingerprint analysis. Cryptography and gloves are both dirt-cheap and widely available. In fact, you can download good cryptographic software from the Internet for less than the price of a good pair of gloves.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Propose to an Englishman any principle, or any instrument, however admirable, and you will observe that the whole effort of the English mind is directed to find a difficulty, a defect, or an impossibility in it. If you speak to him of a machine for peeling a potato, he will pronounce it impossible: if you peel a potato with it before his eyes, he will declare it useless, because it will not slice a pineapple.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“The NSA employs more mathematicians, buys more computer hardware, and intercepts more messages than any other organization in the world.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“like Turing and the cryptanalysts at Bletchley Park, the Navajo were ignored for decades. Eventually, in 1968, the Navajo code was declassified, and the following year the code talkers held their first reunion.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“if a message protected by quantum cryptography were ever to be deciphered, it would mean that quantum theory is flawed,”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Enigma was considered invulnerable, until the Poles revealed its weaknesses.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“This apparently innocuous observation would lead to the first great breakthrough in cryptanalysis.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“In fact, Britain had captured thousands of Enigma machines, and distributed them among its former colonies, who believed that the cipher was as secure as it had seemed to the Germans. The British did nothing to disabuse them of this belief, and routinely deciphered their secret communications in the years that followed. Meanwhile,”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Had the Arabs merely been familiar with the use of the mono-alphabetic substitution cipher, they would not warrant a significant mention in any history of cryptography. However, in addition to employing ciphers, the Arab scholars were also capable of destroying ciphers. They in fact invented cryptanalysis, the science of unscrambling a message without knowledge of the key. While the cryptographer develops new methods of secret writing, it is the cryptanalyst who struggles to find weaknesses in these methods in order to break into secret messages. Arabian cryptanalysts succeeded in finding a method for breaking the monoalphabetic substitution cipher, a cipher that had remained invulnerable for several centuries.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Even the Vatican, probably the second most active center of cryptanalysis, would send Soro seemingly impenetrable messages that had fallen into its hands. In 1526, Pope Clement VII sent him two encrypted messages, and both were returned having been successfully cryptanalyzed.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Rejewski had no idea of the day key, and he had no idea which message keys were being chosen, but he did know that they resulted in this table of relationships. Had”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“The French had handed the information from Schmidt to the Poles because they believed it to be of no value, but the Poles had proved them wrong.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“the Arab scholars were also capable of destroying ciphers. They in fact invented cryptanalysis, the science of unscrambling a message without knowledge of the key.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Vigenère’s work culminated in his Traicté des Chiffres (“A Treatise on Secret Writing”), published in 1586. Ironically, this was the same year that Thomas Phelippes was breaking the cipher of Mary Queen of Scots. If only Mary’s secretary had read this treatise, he would have known about the Vigenère cipher, Mary’s messages to Babington would have baffled Phelippes, and her life might have been spared.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“One way to solve an encrypted message, if we know its language, is to find a different plaintext of the same language long enough to fill one sheet or so, and then we count the occurrences of each letter. We call the most frequently occurring letter the “first,” the next most occurring letter the “second,” the following most occurring letter the “third,” and so on, until we account for all the different letters in the plaintext sample.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Cryptanalysis could not be invented until a civilization had reached a sufficiently sophisticated level of scholarship in several disciplines, including mathematics, statistics, and linguistics. The Muslim civilization provided an ideal cradle for cryptanalysis, because Islam demands justice in all spheres of human activity, and achieving this requires knowledge, or ilm. Every Muslim is obliged to pursue knowledge in all its forms, and the economic success of the Abbasid caliphate meant that scholars had the time, money, and materials required to fulfil their duty. They endeavoured to acquire knowledge of previous civilizations by obtaining Egyptian, Babylonian, Indian, Chinese, Farsi, Syriac, Armenian, Hebrew and Roman texts and translating them into Arabic. In 815, the Caliph of Ma'mun established in Baghdad the Bait al-Hikmah ('House of Wisdom'), a library and centre for translation.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“impenetrability of the Navajo code was all down to the fact that Navajo belongs to the Na-Dene family of languages, which has no link with any Asian or European language.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“many shipwrecks and engineering disasters were blamed on faulty tables. These mathematical tables were calculated by hand, and the mistakes were simply the result of human error. This caused Babbage to exclaim, “I wish to God these calculations had been executed by steam!” This marked the beginning of an extraordinary endeavor to build a machine capable of faultlessly calculating the tables to a high degree of accuracy. In 1823 Babbage designed “Difference Engine No. 1,” a magnificent calculator consisting of 25,000 precision parts, to be built with government funding. Although Babbage was a brilliant innovator, he was not a great implementer. After ten years of toil, he abandoned “Difference Engine No.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“quantum cryptography is a system that ensures the security of a message by making it hard for Eve to read accurately a communication between Alice and Bob. Furthermore, if Eve tries to eavesdrop then Alice and Bob will be able to detect her presence. Quantum cryptography therefore allows Alice and Bob to exchange and agree upon a onetime pad in complete privacy, and thereafter they can use this as a key to encrypt a message.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“At the same time as acquiring knowledge, the Islamic civilization was able to disperse it, because it had procured the art of paper-making from the Chinese. The manufacture of paper gave rise to the profession of warraqin, or 'those who handle paper,' human photocopying machines who copied manuscripts and supplied the burgeoning publishing industry. At its peak, tens of thousands of books were published every year, and in just one suburb of Baghdad there were over a hundred bookshops. As well as such classics as Tales from the Thousand and One Nights, these bookshops also sold textbooks on every imaginable subject, and helped to support the most literate and learned society in the world.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“In addition to a greater understanding of secular subjects, the invention of cryptanalysis aslo depended on the growth of religious sholarship. Major theological schools were established in Basra, Kufa and Baghdad, where thelogians scrutinized the revelations of Muhammad as contained in the Koran. The theologians were interested in establishing the chronology of the revelations, which they did by counting the frequencies of words contained in each revelation. The theory was that certain words had evolved relatively recently, and hence if a revelation contained a high number of these newer words, this would indicate that it came later in the chronology. Theologians also studied the Hadith, which consists of the Prophet's daily utterances. They tried to demonstrate that each statement was indeed attributable to Muhammad. This was done by studying the etymology of words and the structure of sentences, to test whether particular texts were consistent with the linguistic patterns of the Prophet.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“He took the messages to a local brewer, who wrapped them in a leather packet, which was then hidden inside a hollow bung used to seal a barrel of beer. The brewer would deliver the barrel to Chartley Hall, whereupon one of Mary’s servants would open the bung and take the contents to the Queen of Scots. The process worked equally well for getting messages out of Chartley Hall.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“a Navajo verb is conjugated not solely according to its subject, but also according to its object. The verb ending depends on which category the object belongs to: long (e.g., pipe, pencil), slender and flexible (e.g., snake, thong), granular (e.g., sugar, salt), bundled (e.g., hay), viscous (e.g., mud, feces) and many others. The verb will also incorporate adverbs, and will reflect whether or not the speaker has experienced what he or she is talking about, or whether it is hearsay. Consequently, a single verb can be equivalent to a whole sentence, making it virtually impossible for foreigners to disentangle its meaning.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“Babbage’s successful cryptanalysis of the Vigenère cipher was probably achieved in 1854, soon after his spat with Thwaites, but his discovery went completely unrecognized because he never published it. The discovery came to light only in the twentieth century, when scholars examined Babbage’s extensive notes. In the meantime, his technique was independently discovered by Friedrich Wilhelm Kasiski, a retired officer in the Prussian army. Ever since 1863, when he published his cryptanalytic breakthrough in Die Geheimschriften und die Dechiffrir-kunst (“Secret Writing and the Art of Deciphering”), the technique has been known as the Kasiski Test, and Babbage’s contribution has been largely ignored.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“the Vigenère cipher belongs to a class known as polyalphabetic, because it employs several cipher alphabets per message. The polyalphabetic nature of the Vigenère cipher is what gives it its strength, but it also makes it much more complicated to use. The additional effort required in order to implement the Vigenère cipher discouraged many people from employing it.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“the development of a fully operational quantum computer would imperil our personal privacy, destroy electronic commerce and demolish the concept of national security. A quantum computer would jeopardize the stability of the world.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“It is quite possible that British Intelligence demanded that Babbage keep his work secret, thus providing them with a nine-year head start over the rest of the world.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

“French listening posts learned to recognize a radio operator’s fist. Once encrypted, a message is sent in Morse code, as a series of dots and dashes, and each operator can be identified by his pauses, the speed of transmission, and the relative lengths of dots and dashes. A fist is the equivalent of a recognizable style of handwriting.”
― Simon Singh, quote from The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography

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