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An Archeology of Cryptography: Rewriting Plaintext, Encryption, and Ciphertext

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An Archeology of Cryptography: Rewriting Plaintext, Encryption, and Ciphertext An Archeology of Cryptography: Rewriting Plaintext, Encryption, and Ciphertext By Isaac Quinn DuPont A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Faculty of Information University of Toronto © Copyright by Isaac Quinn DuPont 2017 ii An Archeology of Cryptography: Rewriting Plaintext, Encryption, and Ciphertext Isaac Quinn DuPont Doctor of Philosophy Faculty of Information University of Toronto 2017 Abstract Tis dissertation is an archeological study of cryptography. It questions the validity of thinking about cryptography in familiar, instrumentalist terms, and instead reveals the ways that cryptography can been understood as writing, media, and computation. In this dissertation, I ofer a critique of the prevailing views of cryptography by tracing a number of long overlooked themes in its history, including the development of artifcial languages, machine translation, media, code, notation, silence, and order. Using an archeological method, I detail historical conditions of possibility and the technical a priori of cryptography. Te conditions of possibility are explored in three parts, where I rhetorically rewrite the conventional terms of art, namely, plaintext, encryption, and ciphertext. I argue that plaintext has historically been understood as kind of inscription or form of writing, and has been associated with the development of artifcial languages, and used to analyze and investigate the natural world. I argue that the technical a priori of plaintext, encryption, and ciphertext is constitutive of the syntactic iii and semantic properties detailed in Nelson Goodman’s theory of notation, as described in his Languages of Art. I argue that encryption (and its reverse, decryption) are deterministic modes of transcription, which have historically been thought of as the medium between plaintext and ciphertext. By developing a new understanding of encryption as standing between two agents, I characterize the process in terms of media. As media, encryption technologies participate in historical desires for commodious and even “angelic” transmission, popular until the twentieth century. I identify how cryptanalysis, or “code-breaking,” is distinct from cryptography, and instead relates to language, being associated with the history of machine translation. Finally, I argue that ciphertext is the perspectival, ordered result of encryption—similar to computation—and resists attempts to be spoken. Since ciphertext resists being spoken, its application problematizes the category of language, and has, at least once in antiquity, been considered a means of creating silence. Tis dissertation is the frst of its kind to ofer a historically-rich, ontological analysis of cryptography, which therefore opens the topic to new felds of scholarship and humanistic forms of inquiry. iv Acknowledgement Many colleagues and friends have given me invaluable assistance and support over the years I worked on this dissertation. My committee, Brian Cantwell Smith, Patrick Keilty, Yuri Takhteyev, and Brett Caraway, has for many years challenged me, supported my work, and provided a haven for intellectual curiosity. I would also like to thank my defence examiners, Anthony Enns and Costis Dallas, who provided exemplary critique and feedback. Tis dissertation is not only the product of my time at the University of Toronto. Without my friends and colleagues at the University of Victoria and Western University I would not have been prepared to undertake this work. Trough these formative years many people have ofered me encouragement and support, especially my undergraduate colleagues in philosophy, and my graduate colleagues in library and information science. I am also thankful to have learned a great deal from my many academic mentors over the years, especially Bill Maurer and Taneli Kukkonen. I am fortunate to have received funding from a SSHRC Doctoral Fellowship, two Ontario Graduate Scholarships, an Enhanced MITACS Accelerate Fellowship, and a Litwin Books Award for Ongoing Doctoral Dissertation Research in the Philosophy of Information. My many friends through the years have been unwavering in their friendship and support, especially Bradley Fidler, Robyn Lee, Clayton Lewis, Sean Rupka, Ashley Scarlett, Hannah Turner, and of course, Rory. My family has always encouraged my intellectual goals, but none more than my sister, Michelle Vingo. I owe my greatest debt of gratitude to Alana Cattapan, to whom this dissertation is dedicated. v Table of Contents 1 Towards ubiquitous cryptography 1 1.1 Defnitions and terminological complexity 7 1.2 Ways of understanding cryptography 13 2 Rewriting cryptography 25 2.1 Conditions of possibility 30 2.2 Technical a priori 32 2.2.1 Mapping the technical a priori of cryptography 33 2.3 Rewriting three schemata: Plaintext, Encryption, and 42 Ciphertext Part One: Plaintext 3 Representation in the fourteenth and ffteenth centuries 49 3.1 Epoch of representation 52 3.2 Mimesis, resemblance, and media 53 3.2.1 Ancient theories of mimesis 54 3.2.1.1 Plato’s theory of mimesis 54 3.2.1.2 Aristotle’s theory of mimesis 57 3.2.2 Te age of resemblances 59 3.2.2.1 Conventia in memory technologies 60 3.2.2.1.1. Ramon Lull, convenientia, and the path to Alberti 63 3.2.2.2 Aemulatio, analogy, and sympathy in Trithemius’ magical 67 cryptography 3.3 Type, notation, and plaintext 76 3.3.1 Te printing press as prototype for a notational epoch 77 3.3.1.1 Te persistence of mimesis 82 3.3.2 Alberti: Notation and plaintext 83 4 Language planning in the sixteenth and seventeenth centuries 90 4.1 Language planning and modernity 93 4.1.1 Francis Bacon’s artifcial languages 97 4.1.1.1 Real Characters 103 4.1.1.2 Bi-literal cipher 106 4.2 Te growth of language planning (1605-1686) 109 5 Notation from the eighteenth to the twenty-frst centuries 122 5.1 Discourse network 1800 125 5.2 Discourse network 1900 128 5.3 Notation and mathematical sciences 130 5.4 Discourse network 2000, and the rise of algorithms 133 5.5 Wither the discourse network? 138 5.6 Notation: A theory of plaintext 144 5.6.1 Te representational violence of notation 153 vi Part Two: Encryption 6 Codes and codeworks 158 6.1 What is code? 159 6.1.1 Umberto Eco’s defnition of code 162 6.1.2 Friedrich Kittler’s defnition of code 163 6.2 Agrippa (A book of the dead) 168 6.2.1 Forensic description of Agrippa 170 6.2.1.1 Te compiled binary 173 6.2.1.2 Te cryptographic algorithm 174 6.2.1.3 Encryption efect 177 6.2.1.4 Te “self-destruct” mechanism 177 7 Media of perception 179 7.1 Te primal scene of cryptography 181 7.2 Perception and encryption 184 7.2.1 Te medial limits of encryption 186 8 Communication and transmission 190 8.1 Te angel in the middle 191 8.2 Encrypted transmissions 195 8.3 From Hermes to Iris 200 9 Translation and transcription 204 9.1 History of the “cryptographic-translation” idea 206 9.2 Language and cryptanalysis 215 9.2.1 Invention of cryptanalysis 216 9.2.2 Early twentieth century cryptanalysis 221 9.3 Transcription and the encryption performance 226 Part Three: Ciphertext 10 Otherness and order 233 10.1 Cryptographic order 235 10.1.1 Te study of order 241 10.1.2 Perspectival ordering 243 10.2 Andrés Ramírez Gaviria: “Between forms of representation 246 and interpretation” 10.2.1 Art at the intersection of code and mimesis 247 10.2.2 Codes and secrecy 253 vii 11 Silence 261 11.1 Te foil: Te skytale is not a cryptographic device 262 11.2 Te argument: Te skytale is a cryptographic device, for 266 silence 11.3 Ontological and phenomenological account of silence 269 11.4 Silent ciphertext 273 12 Epilogue 279 12.1 From money to law to politics 280 12.2 Open secrets 285 Appendix A. Glossary 290 Bibliography 293 viii List of Figures Figure 2.1: Construction of mapping of domains of cryptography, from Kahn’s Codebreakers. Figure 2.2: Redrawn map of domains of cryptography, from Zielinski’s Deep Time of the Media. Figure 2.3: My mapping of the domains, positivities, and technical a priori of cryptography. Figure 2.4: Diagram of semantics of encryption Figure 3.1: “Visual alphabet” from J.H. von Romberch’s Congestorium Artifciose Memorie (1520). Figure 3.2: First fgure, denoted by A, from Lull’s Ars Brevis (1308/1584). Figure 3.3: Forth fgure, from Lull’s Ars Brevis (1308/1584). Figure 3.4: Cipher wheel from book fve, fgure two of Trithemius’ Polygraphia (1561). Figure 3.5: Codes for invoking the Angel of Saturn, from book three, table three of Trithemius’ Steganographia. Figure 3.6: Setting type in a print shop, from plate 5 of Nova Reperta (c. 1580- 1605). Figures 3.7: Detail of stenographic writing from print edition of Mercury (1641) Figure 3.8: Detail of sound alphabet from print edition of Essay (1668). Figure 3.9: Reconstruction of Alberti’s Descriptio Urbis Romae (c. 1433) mechanism. Figure 3.10: Te rotating horizons of Alberti’s cipher wheel and attached by string, from De cifris (1466). Figure 4.1: Bacon’s “Bi-literate alphabet,” from Of the Advancement and Profciencie of Learning (1623). Figure 4.2: Kircher’s code machine, illustrated in Gaspar Schott’s Organum Mathematicum (1665). Figure 4.3: Wilkins’ system of encryption by Points, Lines, and Figures. Figure 5.1: Figure 4 [vowel resonator] from Tentamen Resolvendi Problema ab Academia Scientiarum Imperiali Petroplitana ad annum 1780 Publice Problema. Figure 5.2: Political cartoon satirizing American universities, from W.E.B. DuBois Club newsletter. Figure 6.1: Contestant Jeremy Cooper’s graphical depiction of the decryption process. Figure 9.1: Shannon’s model of communication. Figure 9.2: Reproduction of al-Kindi’s letter frequency table Figure 9.3: Friedman’s comparison of uniliteral frequency distribution tables ix Figure 9.4: A diagrammatic depiction of the parallel between musical performance and encryption performance.
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