CRYPTOGRAPHY

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CRYPTOGRAPHY

• Lecture 9
• Language as a cipher

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LANGUAGE

• A foreign language is a great cipher if there
  is no one who knows it.
• We will talk about 3 language ciphers
• Hieroglyphics (the Rosetta stone)
• Linear B
• The Navajo code talkers
• The first 2 examples feature unintentional
  encryption. The third example represents the
  successful use of an obscure language in a
  military setting.

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Rosetta Stone
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The Rosetta stone

• For centuries, Hieroglyphics remained a mystery.
  The earliest examples of hieroglyphics date back
  to 3000 BCE and were in use for the next 3500
  years.
• Hieroglyphs were ornate writings suitable for
  temple and palace walls.
• Hieratic was an everyday script, in which every
  hieroglyph was replaced by a simpler symbol,
  which was faster to write.

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The Rosetta stone

• In 600 BCE hieratic was replaced by an even
  simpler script called demotic.
• Hieroglyph, hieratic and demotic were three
  versions of the same alphabet. Almost like 3
  fonts.
• All these fonts are phonetic (but we didnt know
  that for a while)

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The Rosetta stone

• These scripts were used for over 3000 years by
  the ancient Egyptians for every aspect of life.
  At the end of the fourth century CE this script
  vanished. The last samples of ancient Egyptian
  writing is seen in a temple inscription on 394 CE
  and some demotic graffiti has been dated to 450
  CE.
• The ancient Egyptian scripts were outlawed by the
  Christian Church in order to eradicate the link
  to Egypts pagan past.

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The Rosetta stone

• The ancient Egyptian scripts were replaced by
  Coptic, a script consisting of the 24 letters of
  the Greek alphabet plus 6 demotic characters to
  represent uniquely Egyptian sounds.
• Coptic script dominated and the ancient scripts
  were totally forgotten. The ancient language
  evolved into a language which became known as
  Coptic, but which was wiped out in the 11th
  century by the spread of Arabic. Any link to the
  past was lost.

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The Rosetta stone

• In the 17th century, a renewed interest in
  hieroglyphs was awakened. But all attempts to
  read the hieroglyphs were based on the mistaken
  premise that the hieroglyphs were semagrams
  that each character represented a complete idea.
  
• No one was willing to accept or even consider
  that the hieroglyphs were in fact phonograms.
  The belief was that phonetic spelling was too
  advanced for an ancient civilization.

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The Rosetta stone

• The idea that hieroglyphs were picture writing
  was strengthened by the fact that even in the 1st
  century BCE, foreigners such as Diodorus Siculus,
  a Greek historian, described the hieroglyphs in
  terms suggesting picture writing. A 17th century
  German priest by the name of Athanasius Kircher,
  an Egyptologist and cryptographer who wrote a
  book on hieroglyphs, explaining them as
  picture-words.

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The Rosetta stone

• The idea that hieroglyphs were picture writing
  was strengthened by the fact that even in the 1st
  century BCE, foreigners such as Diodorus Siculus,
  a Greek historian, described the hieroglyphs in
  terms suggesting picture writing. A 17th century
  German priest by the name of Athanasius Kircher,
  an Egyptologist and cryptographer who wrote a
  book on hieroglyphs, explaining them as
  picture-words.

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The Rosetta stone

• So, we have a script corresponding to a dead
  language. Can we decipher it?
• No. If there is nothing to hold on to, we cannot
  figure out what the script means.

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The Rosetta stone

• In 1798, Napoleon was busy invading Egypt. Added
  to his military force were scientists, historians
  and draftsmen.
• In 1799, a slab was found in the town of Rosetta
  which had writing on it in Greek, demotic, and
  hieroglyphs.
• The stone was taken to Cairo, then to Alexandria.
  After the wars were over, Britain obtained the
  Rosetta stone and it moved to the British museum
  in 1802.

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The Rosetta stone
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The Rosetta stone
The Rosetta stone has the same message on it in 3
different scripts.
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Greek
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Hieroglyphic
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Demotic
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The Rosetta stone
Two of which represent a language no one had
spoken for at least 8 centuries. Even given the
message in Greek, how could that be used to
explain the message in Coptic or in ancient
Egyptian?
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The Rosetta stone
Thomas Young was born in 1773. He was a child
prodigy, reading Greek, Latin, French, Italian,
hebrew, Chaldean, Syriac, Samaritan, Arabic,
Persian, Turkish, and Ethiopic by the age of
14. He became fascinated by the Rosetta stone and
started studying it. First he noticed a set of
hieroglyphs surrounded by a loop, called a
cartouche. He thought that this is looped
because it represents something (or more likely
someone) important, probably Ptolemy, the Pharaoh
mentioned in the Greek.
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(No Transcript)
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Thomas Young

• Young repeated this process with another
  cartouche he assumed was the queen Berenika.
• He identified many of the 13 hieroglyphs
  correctly.
• Then he stopped. He did not seem to be able to
  accept that indeed hieroglyphs were phonetic. He
  explained that the ones he found were written
  phonetically because they were Greek names, so
  they had no real hieroglyph representation.

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Jean-Francois Champollion

• In 1800, Champollion was 10 years old, and was
  introduced to hieroglyphs by Fourier.
• Fourier explained that no one could read these
  hieroglyphs
• Champollion swore he would some day.
• In 1822, he applied Youngs approach to other
  cartouches

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Jean-Francois Champollion
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Now Champollion had the phonetic meaning of many
hieroglyphs. A few more became clear when he was
looking at a cartouche that, given his prior
knowledge, could be deciphered as A L ? S E ? T
R ?Champollion was certain that this
spelledALKSENTRSthat is, Alexandros or
Alexander.All these names were still foreign,
perhaps phonograms were only used for foreign
names?
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Champollion focused on a cartouche containing
only 4 hieroglyphs.
The last two symbols were already known to
represent S. So the cartouche read ??SS Now
Champollion has a vast knowledge of languages and
although Coptic was a dead language, it was
fossilized in the liturgy of the Christian Coptic
Church, which Champollion was very familiar with.
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What if the first symbol in the cartouche was a
semagram representing the sun. In Coptic, the sun
is RA. This would make the missing letter M and
the cartouche would read RAMSS
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The use of the semagram representing the sun is
an example of rebus writing, like BEE LEAF
BELIEF But the big breakthrough was that the
semagram representing sun had to be read RA (not
helio, which would be the Greek) which is the
Coptic word for SUN. Now Champollion knew which
language the hieroglyphs were in, could identify
everything else. From then on, hieroglyphs could
be read by archeologists.
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LINEAR B
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More ancient languages

• After conquering hieroglyphs, archeologists went
  on to decipher other ancient texts, such as the
  Babylonian cuneiform and the Turkish Kok-Turki
  runes, and the Brahmi alphabet of India.
• Other scripts remain for which there are no cribs
  (like cartouches)
• Linear B was a Cretan script dating back to the
  Bronze age which was deciphered with no crib.

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More ancient languages

• After conquering hieroglyphs, archeologists went
  on to decipher other ancient texts, such as the
  Babylonian cuneiform and the Turkish Kok-Turki
  runes, and the Brahmi alphabet of India.
• Other scripts remain for which there are no cribs
  (like cartouches)
• Linear B was a Cretan script dating back to the
  Bronze age which was deciphered with no crib.

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Crete
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Ancient Crete

• Sir Thomas Evans was interested in the period of
  Greek history described by Homer in the Illiad
  and the Odyssey.
• E.g. The Trojan war
• Some scholars dismissed these things as legends,
  but in 1872 Heinrich Schliemann uncovered the
  site of Troy, close to the Western coast of
  Turkey.

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Ancient Crete

• Between 1872 and 1900 more evidence was
  discovered to show a rich Hellenic period between
  2800 and 1100 BCE
• On the Greek mainland, Mycenae was the center of
  archeological finds. However, no form of writing
  was found.
• Sir Arthur could not accept that such a
  sophisticated society had no writing.

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Ancient Crete

• Sir Arthur found, through antiquities dealers,
  seals originating from Crete, particularly
  Knossos.
• Knossos was home to the palace of the king Minos,
  the center of an empire that dominated the
  Aegean.
• Sir Arthur set out for Crete and began excavating.

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Ancient Crete

• The results were swift and spectacular. He
  unearthed a large castle.
• On March 31, Sir Arthur found a single clay
  tablet with an inscription
• A few days later, a wooden chest full of
  inscribed clay tablets were found.
• These tablets were baked by the fire that
  destroyed the palace. They were very clear and
  easy to read.

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Ancient Crete

• Three sets of tablets were found. The third set
  was the most recent
• The script on it was called Linear B.
• Aside from not having a crib, the main problem
  was that no one knew what language linear B was
  in.

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Linear B
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Features of Linear B

• The direction of writing was left to right.
• There were 90 distinct characters
• Purely alphabetic scripts have between 20-40
  characters (We have 26, Russian has 36, Arabic
  has 28)
• Semagram based languages have hundreds, or
  thousands of characters (Chinese has over 5000)
• Syllabic alphabets have between 50 and 100.
• So the writing was syllabic

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The language of Linear B

• The script looked like classical Cypriot script,
  which was known to be a form of Greek script used
  between 600 and 200 BCE
• But the most common final consonant in Greek is
  s, and so the most common final character should
  have been the corresponding in the Cypriot
  script. This is found in linear B, but not at
  the end of the word.
• The consensus was that the script of linear B
  later evolved into the Cypriot script, but that
  the language was not Greek.

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The language of Linear B

• Sir Arthur Evans was adamantly set against Linear
  B being Greek for another reason
• Excavations showed the Minoan Empire to be a
  powerful rival of the Mycenaeans, probably the
  dominant rival, so it did not seems that they
  would adopt the language used in Mycenaea.

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Classification of the characters in Linear B

• Alice Kober, a classicist from Brooklyn colege
  focused on the structure of the language. She
  noticed that many words formed triplets, it
  looked like the same word appearing in 3 slightly
  different forms. It looked that the stem was
  identical, but there were different endings.
  This suggests a highly inflective language.
• She assigned to each sign a number, so that even
  though she could not associate a phonetic value
  to each sign, she figured out what the
  relationships were.

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Classification of the characters in Linear B

• Each sign was a combination of a consonant and a
  vowel sound. So you could have, e.g.
• MI BI
• MA BA
• ME BE
• MO BO
• A table of these values would show you that a
  certain character shared a vowel with another
  character, or that two characters shared the same
  consonant.
• Alice Kober died of cancer before she could go
  much further.

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Cracking Linear B

• Michael Ventris wanted to crack linear B. He
  started with Alice Kobers discoveries.
• Each character is a CV combination, but what
  happens if the vowel has to appear alone?
• He hypothesized that there must be some character
  for when a vowel comes in the beginning of a
  word.
• He characterized all of these in a table.
• Then he saw the words 08-73-30-12, 70-52-12 and
  69-53-12 appear over and over again. He guessed
  that these must be the names of important cities.
  His table showed the 08 was one of those
  characters which only appear in the beginning of
  a word and represent a vowel.

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Cracking Linear B

• The only city known to begin with a vowel was
  Amnisos so that 08-73-30-12 should be A MI NI
  SO with the final s missing.
• According to the table, this meant that 12, which
  represented SO was in the same vowel column and
  the seventh consonant row.
• Two other signs, 70 and 52, were in the same
  vowel column, so they must end with an O sound
  too. Thus the second city mentioned 70-52-12 so
  it must be ?O-?0-SO
• What if this represented the city Knossos? Then
  we have KO-NO-SO and we know 2 new consonant
  sounds for the entire table. Also, since 30 and
  52 were in the same consonant row (N) this was a
  sign that he was on the right track.

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Cracking Linear B

• Next he looked at 69-53-12 ??-?I-SO where 69
  does not have the vowel I or the vowel O. The
  name TU-LI-SO (Tulissos) suggested itself. Now
  he had 8 signs, and each one of those gave rise
  to many others, because of the combination of
  vowels and consonants.
• Finally, he deciphered the final words on most
  columns of figures, 05-31 as TO-SA and 05-12 as
  TO-SO, similar to the Greek words for
  TOTALtossos and tossa
• But this suggests that Linear B was Greek! He
  did not accept that this could be true, but
  continued to pursue this line of reasoning

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Sounds in Linear B
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Sounds in Linear B

• Using the table, he deciphered more words poimen
  (shepherd), kerameus (potter), etc.
• He also deciphered some phrases, with no
  problems.
• He came to the conclusion that this must be a
  form of ancient Greek.
• John Chadwick was an expert in ancient Greek and
  joined in with Ventris. Together they completely
  deciphered the script.
• Now linear B tablets could be read history
  revealed itself.

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The Navajo code talkers
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Language as cipher

• One of the key Ideas is that you can only
  decipher a message in a language you know.
• The Rosetta stone was helpful only because the
  Coptic language was kept alive in the Christian
  Coptic Church.
• Linear B could be deciphered because it was in
  ancient Greek.

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Language as cipher

• But if you dont know the language, how can you
  decipher the message?
• This was the idea behind one of the most
  successful cryptographic endeavours the Navajo
  code talkers.

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Navajo code talkers

• The Navajo Code Talkers, whose ranks exceed 400
  during the course of World War II in the Pacific
  Theater.  Have been credited with saving
  countless lives and hastening the end of the war.
  The Code Talker's served in all six Marine
  divisions from 1942 to 1945.
• The Code Talker's primary job was to talk and
  transmit information on tactics, troop movements,
  orders and other vital battlefield information
  via telegraphs and radios in their native
  dialect.  A major advantage of the code talker
  system was its speed. The method of using Morse
  code often took hours where as, the Navajos
  handled a message in minutes.   It has been said
  that if was not for the Navajo Code Talker's, the
  Marines would have never taken Iwo Jima.    
• The Navajo's unwritten language was understood by
  fewer than 30 non-Navajo's at the time of WWII. 
  The size and complexity of the language made the
  code extremely difficult to comprehend, much less
  decipher.  It was not until 1968 that the code
  became declassified by the US Government.    

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Navajo code talkers

• The Navajo Code Talkers, whose ranks exceed 400
  during the course of World War II in the Pacific
  Theater.  Have been credited with saving
  countless lives and hastening the end of the war.
  The Code Talker's served in all six Marine
  divisions from 1942 to 1945.
• The Code Talker's primary job was to talk and
  transmit information on tactics, troop movements,
  orders and other vital battlefield information
  via telegraphs and radios in their native
  dialect.  A major advantage of the code talker
  system was its speed. The method of using Morse
  code often took hours where as, the Navajos
  handled a message in minutes.   It has been said
  that if was not for the Navajo Code Talker's, the
  Marines would have never taken Iwo Jima.    
• The Navajo's unwritten language was understood by
  fewer than 30 non-Navajo's at the time of WWII. 
  The size and complexity of the language made the
  code extremely difficult to comprehend, much less
  decipher.  It was not until 1968 that the code
  became declassified by the US Government.