Exhibit 5 Message 2

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Exhibit 5 Message 2
Topic Started: Jul 9 2009, 03:54 AM (121 Views)
Gerry StPierre	Jul 9 2009, 03:54 AM Post #1
Just registered Posts: 14 Group: Members Member #3,269 Joined: June 5, 2009	Quote: ... three messages of approximately 25 words each as an "in depth" specimen of Chaocipher (as opposed to the original exhibits in Silent Years, each of which was enciphered in a single continuous key). The plaintext, which is typical English prose, is taken from Stewart C. Easton's book, Rudolf Steiner: Herald of a New Epoch For some reason, when reading about the three messages in Exhibit 5 I got the sense that they may be quotes from the book indicated. Looking through the first two chapters available on google, I found one instance where a quotation matched one of the three message lengths (121, 140, 162). Quote: If anyone possesses the perception of the spiritual world in himself very deep glimpses can be obtained into this world through someone else who has a firm footing in it. I count this as 30 words with a length of 140 characters without the punctuation. The second message in Exhibit 5 is also 140 characters long. IFANYONEPOSSESSESTHEPERCEPTIONOFTHESPIRITUALWORLDINHIMSELFVERYDEEPGLIMPSESCAN ENWSCEAQGIVIDEMWUMSNZMNTVUFDLBJKKMRHHSNBKTJBHVPTWHFMQQJPGRWFFVJMDHFUZOXEOZTMK ________________________________1_______1 BEOBTAINEDINTOTHISWORLDTHROUGHSOMEONEELSEWHOHASAFIRMFOOTINGINIT ZSAMJYRLSQSXUZYEKRJBFRESGGFXFEGXLPWTWLZAVIMTBDTQBLVRZVEMMTLXITZ _2______2 I'm not sure if this is useful, but I did find it to be an interesting coincidence. mosher did notice that this does result in two identities (i.e., identical pt/ct pairs) in less than nine characters (which I've marked above as well)



mosher	Jul 9 2009, 05:40 AM Post #2
Member Posts: 41 Group: Moderators Member #3,268 Joined: May 26, 2009	Hi Gerry, Kudos for starting this thread. I'm sure it will blossom to touch upon many very relevant issues regarding Exhibit 5 in Kruh & Deavours's (K&D) article (found here, beware the one dropped letter in message #3 described here). For other readers, Gerry's 140-letter text comes from the following sentence on page 18 in Stewart C. Easton's "Rudolf Steiner: Herald of a New Epoch": Quote: He commented in his autobiography that "if anyone possesses the perception of the spiritual world in himself very deep glimpses can be obtained into this world through someone else who has a firm footing in it." Gerry's idea is that K&D may have specifically used a passage marked as a quotation from Easton, rather than a regular sentence. The idea is an interesting one. The hypothesis could be bolstered by finding other quotations in Easton that match the required lengths. From my experience with K&D's previous articles, I would not give them the credit of having picked the texts cleverly. I'm not even convinced that the underlying texts are whole sentences. I would not be surprised if they started a sentence and broke it off halfway through. See The Chaocipher Clearing House Progress Report #5 for my thoughts on this issue. In an early e-mail exchange with osric, he suggested that tackling Exhibit 5 with its three "in-depth" messages might be the best course to take. After trying to tackle Exhibit 1 for almost a year, I tend to agree with him. The reasoning is that, although little information is known about them, they are three messages that are somehow related (i.e., "in-depth). It is hoped something can be gleaned from that. Even a relatively insecure cipher system with an erratic keying sequence can defy analysis if only one message is given. Given two in-depth messages, even a one-time pad can be solved (e.g. VENONA)! D&K's messages give a hope of leveraging one message against the others. I will try to continue the search for quotations or other matching sentences for the Exhibit 5 messages. Thanks again for starting this thread!



osric	Jul 9 2009, 09:18 AM Post #3
Advanced Member Posts: 51 Group: Members Member #3,254 Joined: March 15, 2009	Quote: mosher did notice that this does result in two identities (i.e., identical pt/ct pairs) in less than nine characters (which I've marked above as well) These two identities have spacings of 8 and 7. There are no identities in Exhibit 1 with spacings less than 9 (see CHAOCIPHER: ANALYSIS AND MODELS Jeffrey A. Hill, February 28, 2003, Revised April 12, 2009 at TCCH) which I am afraid suggests this otherwise appealing conjunction of plain and ciphertext is unlikely to be correct. But there may be other quotations that fit! Edited by osric, Jul 9 2009, 09:19 AM.



mosher	Jul 9 2009, 10:55 AM Post #4
Member Posts: 41 Group: Moderators Member #3,268 Joined: May 26, 2009	Jeff Hill's 'Hidden Markov Model' using steps of 1, 2, or 4 actually allows theoretically for a pt/ct identity within seven (7) steps. Seven steps consisting of (2, 4, 4, 4, 4, 4, 4) or any permutations thereof will result in exactly 26 shifts, enabling a pt/ct identity at distance 7. The probability of (2,4,4,4,4,4,4) occurring is (0.25)^7 = 0.000061035+. There are seven permutations of (2,4,4,4,4,4,4) so the final probability of a pt/ct identity within seven steps is ~ 0.000061035 x 7 = 0.000427245. Since we don't know the pt/ct equivalences for the 140-letter message, let's make a worst-case assumption that all matching ct letters at a distance of seven have matching pt letters. For this message there are five sets of matching ct letters at a distance of seven (I shifted the message seven positions against itself and looked for column matches): A] (ENWSCEA)QGIVIDEMWUMSNZMNTVUFDLBJKKMRHHSNBKTJBHVPTWHFMQQJPGRWFFVJMDHFUZ B] _________ENWSCEAQGIVIDEMWUMSNZMNTVUFDLBJKKMRHHSNBKTJBHVPTWHFMQQJPGRWFFV ..._______________________x____________________________________________x__ A] OXEOZTMKZSAMJYRLSQSXUZYEKRJBFRESGGFXFEGXLPWTWLZAVIMTBDTQBLVRZVEMMTLXITZ B] JMDHFUZOXEOZTMKZSAMJYRLSQSXUZYEKRJBFRESGGFXFEGXLPWTWLZAVIMTBDTQBLVRZVEM(MTLXITZ) ...________________x_____________x______x Although these can theoretically occur in message #3, we would expect 0.000427245 x 5 = 0.002136225 such occurrences. As osric points out, our encountering two such identities is statistically highly improbable. This assumes, of course, that Jeff Hill's models are fundamentally correct. At the present time, we believe it is. Nonetheless, the search for other possible quotes or sentences should most definitely continue. Stay tuned! Moshe



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