The Philosophical Breakfast Club
Page 43
Babbage was the first to develop this method of deciphering the Vigenère cipher, yet the solution is known as the Kasiski examination, or the Kasiski test, because in 1863 Friedrich W. Kasiski, a retired major in the Prussian army, described this method in his pamphlet Die Geheimschriften und die Dechiffrir-Kunst. Although Babbage invented the same method nearly ten years earlier, he never publicized his accomplishment, and he lost the chance to gain fame for it.30
Why did Babbage keep secret his success in finding a method of deciphering le chiffre indéchiffrable? In the dispute with Thwaites, he never revealed his identity, hiding forever behind the “C” signature in the pages of the Journal. What he published in those pages was only a brief description of how he broke Thwaites’s cipher, not the general solution to the Vigenère. This incomplete explanation was not even published in a scientific journal, but in the journal of the Society of the Arts, hardly the platform for a groundbreaking achievement. And although he had been sending numerous letters about deciphering during this time to both Herschel and Augustus De Morgan, both of whom were also intrigued with ciphers and codes, in none of the letters that remain extant today did Babbage inform his friends that he had deciphered the chiffre indéchiffrable. Not taking credit for something so impressive is out of character for Babbage, to say the least.
One intriguing—but merely speculative—explanation for this uncharacteristic modesty is that Babbage may have been working for the British government, cracking the code that could give them an edge in the war in Crimea. At the end of March 1854, five months before Thwaites’s letter appeared in the Society of the Arts’s journal, Britain and France had declared war on Russia. The two old enemies had forged an uneasy alliance in order to fight the greater evil, Russia, which had begun a campaign of aggressive annexation in the Middle East, targeting Turkey to gain access to its warm-weather ports, and demanding control of some of the holy sites under Turkish control in Palestine. The Russians were relying on the Vigenère, among other ciphers, to send secret military messages by telegraph. Although the French had used the Vigenère extensively during their wars with Britain, they had not succeeded in discovering how to break the cipher—so the French, like the English, had no way to read messages intercepted from the Russians. Having the means to decipher such messages would give the Royal Navy an enormous advantage, similar to that gained by Britain when it cracked the German “Enigma” cipher during World War II. Indeed, it was shortly after this period that Babbage returned, for the last time, to the plans of his Analytical Engine, raising the possibility that he was tinkering with the idea of creating a code-breaking machine, such as the “Colossus” machine built by the British at Bletchley Park during the Second World War to decipher the German “Enigma.” But any advantage gained by knowing how to crack the code would cease if Babbage publicized his achievement; the Russians would then immediately stop using the Vigenère. If Babbage had been working for military intelligence, his success would have been a military secret, and publicizing it would have been treason, a capital offense.
There is no clear evidence in his papers, or at the National Archives of Britain at Kew, that Babbage was working for the military, or that the solution he devised was ever applied to intercepted messages before the end of the war in 1856—though perhaps in this case the lack of evidence is a form of evidence, for surely Babbage’s work for the government would have been considered top secret, omitted even from written government reports. Babbage may have been giving a hint of his involvement in the pages of the Journal. By applying Babbage’s rule for finding the key, one expert has determined that the key term used by Babbage in encrypting the Thwaites passage was the rather provocative expression “Foreign Supremacy.”31
Another tantalizing clue pointing to Babbage’s involvement with the military is a draft of a letter from a mysterious “F. Williamson” found in Babbage’s papers. The letter is addressed to an anonymous “Lord” who had recently given a speech about the use of ciphers over the telegraph. This must be Lord Palmerston, the newly appointed prime minister, who had spoken in the House of Commons in May about the reason why the government was not publicly releasing certain messages that had been received over the telegraph in cipher; frustrations about this had been expressed a week before in a Times editorial.32 In that speech, Lord Palmerston had defended his government’s reticence, noting that if someone had both the cipher text and the plain text, he would be able to discover the cipher and use it to decipher other secret messages.33 The letter-writer countered this claim by referring to the undecipherable cipher of “his friend” Mr. Thwaites, noting that even though he had published the cipher text and plain text, it was impossible to determine the cipher itself. The writer gushed that “Mr. Tw. is perhaps the greatest decypher [sic] in Europe!” He advised Palmerston to forward Thwaites’s name and address to Mr. Hammond at the Foreign Office—this would be Edmund Hammond, recently named undersecretary of state in charge of Secret Service, a position he would hold for another twenty years, and in which Hammond would later be described as “keeping everything … under the solemn pall of secrecy.34
Why would a draft of this letter find its way to Babbage? Both Lord Palmerston and Williamson, whoever he was, would have read in the Times a few weeks earlier about Babbage’s talents in breaking the cipher used by Captain Childe. Did Palmerston—who had been a student decades earlier of Babbage’s friend Dugald Stewart in Edinburgh—request that this mysterious Mr. Williamson send Babbage a copy of his letter, so that Palmerston could solicit Babbage’s advice about this cipher? Or did Williamson send Babbage the draft of the letter asking for his opinion before sending it on to Palmerston? Short of uncovering a new batch of correspondence on this topic, we will never learn the truth about this mystifying letter.
In his Passages from the Life of a Philosopher, published in 1864, Babbage takes credit for every one of his actual achievements and several that are more dubious—for example, being the mastermind behind the foundation of Section F of the British Association, which was actually due to the inspiration of Jones and the careful planning of Whewell; and even being the host of the meetings of the Philosophical Breakfast Club, when they were really held in Herschel’s rooms. It is inconceivable that Babbage would have kept secret his success at breaking the “unbreakable cipher”—a work of mathematical, statistical, and intuitive genius—unless he had been ordered to do so. By the time Babbage wrote the Passages, Kasiski’s pamphlet had appeared in Prussia, but it was not translated into English, so Babbage would not have known that the solution had already been exposed (the pamphlet did not receive much attention, even in Prussia). Four years later, in 1868, the mathematician and author of Alice’s Adventures in Wonderland, Charles Dodgson, writing under his pen name, Lewis Carroll, deemed the Vigenère cipher “unbreakable” in a short piece he wrote called “The Alphabet Cipher.”35 Babbage would have believed that he was still under the command to keep his method for decrypting the Vigenère cipher a secret. In the absence of further evidence, the question of Babbage’s involvement with the British Secret Service during the Crimean War will remain, as one historian has put it, “Mr. Babbage’s Secret.” If Babbage did put his considerable skills in statistics to the service of the state, and the public good, by providing a means to end the Crimean War sooner, he was at last, in his sixties, returning to one of the original aims of the Philosophical Breakfast Club.
WHILE BABBAGE WAS busy breaking the “unbreakable cipher,” Charles Darwin was still hard at work attempting to decipher the “mystery of mysteries,” as Herschel had called it, the origin of new species. In 1837 and 1838—after attending Babbage’s soirées, and reading Malthus’s Essay on the Principle of Population—Darwin had reached the conclusion that species change, that one species, over time, transforms or transmutes into another. Darwin had therefore rejected the “special creation” of species, the belief that God had intervened in the natural world to create every species, each one remaining the same for all time until (a
s was clearly the case for some) it died out, becoming extinct. Darwin had already described his theory and his main arguments for it in a short sketch of his view that ran to thirty-five pages, written in 1842, and in a longer essay, written in 1844, neither of which he published. He would continue to refine his theory, and collect evidence for it, for another fifteen years before he would disclose it to the world.36
In the 1844 essay he began, as he would in the larger book, with the topic of variation among domestic animals. Individual sheep, dogs, and pigeons are born with slight differences or variations in size, color, and other characteristics. Because some of these variations are inherited, breeders are able to choose or “select” traits they wish to perpetuate or amplify by carefully pairing animals together. For example, dogs with a particularly good sense of smell could be bred together, and soon one would have a prime pack of hunting dogs. Darwin chose his examples well: he knew that his readers would be familiar with examples of domestic variation, either from experience on farms, or from knowledge of the very popular hobbies of pigeon and dog breeding.
Variation exists among non-domesticated organisms in nature as well, Darwin argued further. Some of these variations, too, are inheritable. Darwin’s reading of Malthus had led him to realize that overpopulation relative to resources was a problem not only for human populations, but also for animal and plant species. Malthus had argued that populations increase geometrically over generations, but their food supply does not. Darwin saw that Malthus was correct at least in suggesting that there was a kind of natural struggle—what he would later term a “struggle for existence”—among individuals of a species, and between different species, competing over existing resources. Individuals more successful at using those resources because of a “variation” lacking in other members of the population would live longer and thus be more likely to produce greater numbers of offspring, many of which would inherit the helpful variation. Wolves that could run faster would be more likely to catch prey first and thus be more likely to survive in an environment with diminishing numbers of edible animals relative to the growing wolf population. Their offspring would tend to run faster as well, until over many generations the whole species of wolves had been transmuted into a faster species. This was a kind of “natural selection,” analogous to the artificial selection of the farmer or the breeder. In this way, new species are created—and are created so as to be best suited for their environments. Darwin thus presented an alternative option to explain the fitness of species to their environments, one that rested neither on the scientifically irreputable notion of chance nor on God’s individual creation of each species. Species ended up well suited to their environments not merely by chance, and not because God made them specially that way, but because random variations occurred that made some individuals better able to survive; these individuals did live longer, and produce more offspring, while their cohorts lacking the variation died off, until a new species emerged that was better suited to survive in the the environment. (There is still a component of chance in Darwin’s account, because the variations arise randomly.)
But Darwin had not attempted to publish this essay, which he saw as an outline for the larger, more detailed work he hoped to write someday. Someday, but not yet; still, Darwin hesitated.
Part of Darwin’s initial reticence arose from his realization that the theory would destroy a certain kind of religious faith, the kind that held man to be God’s special creation, a being completely outside of nature while still placed within it. Darwin famously recounted a dream in which a man, probably he himself, was being hanged for murder—the murder of that type of religious conviction.37 He knew his wife, Emma Wedgwood Darwin, had that kind of faith, and he was loath to hurt her—and unwilling to remind her that he did not believe the two of them would be together for eternity, even after death.
At the time of the Beagle voyage, Darwin was a Christian, orthodox enough that his fellow shipmates laughed at him for quoting the Bible as an authority on morality. But, over time, he began to question the orthodox notion of miracles (as Babbage had done) and realized that the Old Testament was a “manifestly false history of the world.” He came to reject Christianity as a divine revelation, even seeing it as a “damnable doctrine.” For a time Darwin continued to believe in God as the creator of the universe, but not as the special creator of each and every species. Rather, Darwin’s new concept of God was like Babbage’s computer-programming God, who set up the world to run His programs, which included the law of gravitation and the law of evolution by natural selection. Ultimately, Darwin would even give up this shred of religious belief, rejecting the existence of any kind of God and any immortal souls.38
Darwin was well aware that he would not be the first to propose the evolution of organic species. Darwin’s own paternal grandfather, Erasmus Darwin, had noted in his book Zoonomia (1794–96) that “all warm-blooded animals have arisen from one living filament,” and that this filament was endowed with the capacity of “continuing to improve by its own inherent activity.” Soon afterwards, Jean-Baptiste Lamarck, in France, had offered the first coherent theory of evolution, asserting that organisms gain and lose characteristics based on their use or disuse, such as the blindness of the mole that lives in darkness, and that properties acquired (or lost) through this kind of interaction with the environment are inherited by offspring (for Lamarck, unlike for Darwin, these characteristics did not arise as random variations). More recently, the still-anonymous author of the Vestiges of the Natural History of Creation, who agreed with much of what Lamarck had argued, had reintroduced Victorian audiences to evolution. The author of that work had used the example of Babbage’s Difference Engine to make the point that just as Babbage’s device operated in accordance with a greater pattern that might not be apparent to the observer, so too the laws that governed the process of species evolution might be invisible to us but nevertheless present.39
Darwin had taken note of the vitriolic reaction of most men of science to the Vestiges. Scientists had overwhelmingly dismissed this book as unscientific, relying as it did on outmoded theories such as the spontaneous generation of maggots in organic matter. Whewell’s friend Adam Sedgwick had accused the writer—whoever he or she might be—of ignoring the type of scientific method endorsed by Whewell and Herschel: the author “builds his castles in the sky.… He does all this, apparently, without having any just conception of the methods by which men, after the toil of many generations, have ascended, step by step, to the higher elevations of physical knowledge—without any even glimmering conception of what men mean when they tell us of Inductive Science and its sober truths.”40
After reading Sedgwick’s review, Darwin admitted to Lyell, “It is a grand piece of argument against mutability of species, and I read it with fear and trembling.”41 Darwin was determined that any book of his would not meet the same fate. He would design his book explicitly to meet the conditions for good inductive science that the experts of the day, Whewell and Herschel, had set out in their works, so that no such criticisms could be made of his work. It would take him nearly fifteen years to achieve that goal. (Darwin was still worrying right before his book was published; he wrote to Asa Gray, the American botanist and a strong supporter of Darwin’s work, that he still felt that “my work will be grievously hypothetical, and large parts by no means worthy of being called induction, my commonest error being probably induction from too few facts.”42)
Darwin had long been impressed with Herschel’s and Whewell’s views of science. Reading Herschel’s book on scientific method when he was an undergraduate at Cambridge “stirred up inside me a burning zeal to contribute to science,” Darwin recalled.43 Whewell also served as a kind of scientific mentor to Darwin. Darwin attended John Henslow’s botany lectures in the company of Whewell, who probably recommended Herschel’s book to his younger colleague. Darwin respected the breadth and depth of Whewell’s knowledge, calling him one of the “best conversers on grave subjects to whom I h
ave ever listened.”44 He was particularly impressed by Whewell’s work on the tides, believing that he “will always rank as one of the great investigators” of the topic.45
Darwin was less awed by Whewell’s Bridgewater Treatise; one of his notes on that text mocks Whewell for his claim that the length of the solar day is twenty-four hours, with twelve hours of night, because that arrangement best suits man’s need for sleep: “whole universe so adapted!!! And not man to planets—instance of arrogance!!!”46 But Darwin’s close reading of the Bridgewater Treatise had led him to realize that he had to show how his theory could offer an alternative explanation for the fitness of organisms to their environment, an explanation that relied neither on pure chance nor on God’s special creation. Whewell’s more sophisticated version of the argument from design was the one Darwin knew he had to take aim at, not Paley’s more simplistic treatment. Darwin would ultimately sandwich his disagreeable view between slices of the digestible, law-based version of natural theology endorsed by Whewell: he had a quote from Whewell’s Bridgewater Treatise on the frontispiece of the book (reminding his readers that “with regard to the material world, we can at least go so far as this—we can perceive that events are brought about not by insulated interpolations of Divine Power, exerted in each particular case, but by the establishment of general laws”), and he ended it with a stirring passage suggesting that God was a Divine Lawmaker, just as Whewell had suggested: “There is grandeur in this view of life,” Darwin tried to convince his audience, “having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been and are being, evolved.”47