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- From: uunet!questrel!chris (Chris Cole)
- Subject: rec.puzzles FAQ, part 4 of 15
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- Summary: This posting contains a list of
- Frequently Asked Questions (and their answers).
- It should be read by anyone who wishes to
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- Date: Mon, 21 Sep 1992 00:08:48 GMT
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-
- ==> cryptology/Voynich.s <==
- The Voynich Manuscript is a manuscript that first surfaced in the court of
- Rudolf II (Holy Roman Emperor), who bought it for some large number of
- gold pieces (600?). Rudolf was interested in the occult, and the strange
- characters and bizarre illustrations suggested that it had some deep
- mystical/magical significance. After Rudolf's court broke up, the
- manuscript was sent to (if memory serves) Athanasius Kircher, with nobody
- on the list having been able to read it. It ended up in a chest of other
- manuscripts in the Villa Mondragone [?] in Italy, and was discovered there
- by Wilfred Voynich, a collector, in about 1910 or so. He took it to a
- linguist who wasn't a cryptanalyst, who identified it as a work by the
- 12th century monk Roger Bacon and produced extended bogus decryptions based
- on shorthand characters he saw in it. A great deal of effort by the best
- cryptanalysts in the country hasn't resulted in any breakthrough. William
- F. Friedman (arguably the best) thought it was written in an artificial
- language. I believe the manuscript is currently in the Beinecke Rare
- Book Collection at [Harvard?].
-
- Mary D'Imperio's paper is scholarly and detailed, and provides an
- excellent starting point for anyone who is interested in the subject.
- David Kahn's "The Codebreakers" has enough detail to tell you if you're
- interested; it also has one or more plates showing the script and some
- illustrations. I believe D'Imperio's monograph has been reprinted by
- Aegean Park Press. A number of people have published their own ideas
- about it, including Brumbaugh, without anybody agreeing. A recent
- publication from Aegean Park Press offers another decryption; I haven't
- seen that one.
-
- If you want *my* guess, it's a hoax made up by Edmund Kelley and an
- unnamed co-conspirator and sold to Rudolf through the reputation of John
- Dee (Queen Elizabeth I's astrologer).
- --
- Jim Gillogly
- {hplabs, ihnp4}!sdcrdcf!randvax!jim
- jim@rand-unix.arpa
-
- I read "Labyrinths of Reason" by William Poundstone recently. I'm
- posting this to so many newsgroups in part to recommend this book, which,
- while of a popular nature, gives a good analysis of a wide variety of
- paradoxes and philosophical quandaries, and is a great read.
-
- Anyway, it mentions something called the Voynich manuscript, which is
- now at Yale University's Beinecke Rare Book and Manuscript Library.
- It's a real pity that I didn't know about this manuscript and go see it
- when I was at Yale.
-
- The Voynich manuscript is apparently very old. It is a 232-page illuminated
- manuscript written in a cipher that has never been cracked. (That's
- what Poundstone says - but see my hypothesis below.) If I may quote
- Poundstone's charming description, "Its author, subject matter, and
- meaning are unfathomed mysteries. No one even knows what language the
- text would be in if you deciphered it. Fanciful picutres of nude women,
- peculiar inventions, and nonexistent flora and fauna tantalize the
- would-be decipherer. Color sketches in the exacting style of a
- medieval herbal depict blossoms and spices that never spring from earth
- and constellations found in no sky. Plans for weird, otherworldly
- plumbing show nymphets frolicking in sitz baths connected with
- elbow-macaroni pipes. The manuscript has the eerie quality of a
- perfectly sensible book from an alternate universe."
-
- There is a picture of one page in Poundstone's book. It's written in a
- flowing script using "approximately 21 curlicued symbols," some of which
- are close to the Roman alphabet, but others of which supposedly resemble
- Cyrillic, Glagolitic, and Ethiopian. There is one tiny note in Middle
- High German, not necessarily by the original author, talking about the
- Herbal of Matthiolaus. Some astrology charts in the manuscript have the
- months labeled in Spanish. "What appears to be a cipher table on the
- first page has long faded into illegibility," and on the other hand, some
- scholars have guessed that a barely legible inscription on the *last*
- page is a key!
-
- It is said to have "languished for a long time at the Jesuit College of
- Mondragone in Frascati, Italy. Then in 1912 it was purchased by Wilfred
- M. Voynich, a Polish-born scientist and bibliophile... Voynich was the
- son-in-law of George Boole, the logician..." A letter written in 1666
- claims that Holy Roman Emperor Rudolf II of Bohemia (1552-1612) bought
- the manuscript for 600 gold ducats. He may have bought it from Dr.
- John Dee, the famous astrologer. Rudolf thought the manuscript was
- written by Roger Bacon! [Wouldn't it more likely have been written by
- Dee, out to make a fast ducat?]
-
- "Many of the most talented military code breakers of this century have
- tried to decipher it as a show of prowess. Herbert Yardley, the
- American code expert who solved the German cipher in WW1 and who cracked
- a Japanese diplomatic cipher without knowing the Japanese language,
- failed with the Voynich manuscript. So did John Manly, who unscrambled
- the Waberski cipher, and William Friedman, who defeated the Japanese
- "purple code" of the 1940's. Computers have been drafted into the
- effort in recent years, to no avail."
-
- Poundstone goes on to describe a kook, Newbold, who was apparently driven
- batty in his attempt to crack the manuscript. He then mentions that one
- Leo Levitov also claimed in 1987 to crack the cipher, saying that it was
- the text of a 12th-century cult of Isis worshipers, and that it
- describes a method of euthanasia by opening a vein in a warm bathtub,
- among other morbid matters. According to Levitov's translation the text
- begins:
-
- "ones treat the dying each the man lying deathly ill the one person who
- aches Isis each that dies treats the person"
-
- Poundstone rejects this translation.
-
- According to Poundstone, a William Bennett (see below) has analysed the
- text with a computer and finds that its entropy is less than any known
- European language, and closer to those of Polynesian languages.
-
- My wild hypothesis, on the basis solely of the evidence above, is this.
- Perhaps the text was meant to be RANDOM. Of course humans are lousy at
- generating random sequences. So I'm wondering how attempted random
- sequences (written in a weird alphabet) would compare statistically with
- the Voynich manuscript.
-
- Anyway, the only source Poundstone seems to cite, other than the
- manuscript itself, is Leo Levitov's "Solution of the Voynich Manuscript,
- A Liturgical Manual for the Endura Rite of the Cathari Heresy, the Cult
- of Isis," Laguna Hills, Calif., Aegean Park Press, 1987, and William
- Ralph Bennett Jr.'s "Scientific and Engineering Problem-Solving with the
- Computer," Englewood Cliffs, New Jersey, Prentice-Hall 1976.
-
- I will check the Bennett book; the other sounds hard to get ahold of! I
- would LOVE any further information about this bizarre puzzle. If anyone
- knows Bennett and can get samples of the Voynich manuscript in
- electronic form, I would LOVE to get my hands on it.
-
- Also, I would appreciate any information on:
-
- Voynich
- The Jesuit College of Mondragone
- Rudolf II
- The letter by Rudolf II (where is it? what does it say?)
- The attempts of Yardley, Friedman and Manly
- The Herbal of Matthiolaus
-
- and, just for the heck of it, the "Waberski cipher" and the "purple
- code"!
-
- This whole business sounds like a quagmire into which angels would fear
- to tread, but a fool like me finds it fascinating.
-
- -- sender's name lost (!?)
-
- To counter a few hypotheses that were suggested here:
-
- The Voynich Manuscript is certainly not strictly a polyalphabetic cipher
- like Vigenere or Beaufort or (the one usually called) Porta, because of
- the frequent repetitions of "words" at intervals that couldn't be
- multiples of any key length. I suppose one could imagine that it's an
- interrupted key Vig or something, but common elements appearing at places
- other than the beginnings of words would seem to rule that out. The I.C.
- is too high for a digraphic system like (an anachronistic) Playfair in any
- European language.
-
- One of the most interesting Voynich discoveries was made by Prescott Currier,
- who discovered that the two different "hands" (visually distinct handwriting)
- used different "dialects": that is, the frequencies for pages written in
- one hand are different from those written in the other. I confirmed this
- observation by running some correlation coefficients on the digraph matrices
- for the two kinds of pages.
-
- W. F. Friedman ("The Man Who Broke Purple") thought the Voynich was
- written in some artificial language. If it's not a hoax, I don't see any
- evidence to suggest he's wrong. My personal theory (yeah, I've offered
- too many of those lately) is that it was constructed by Edward Kelley,
- John Dee's scryer, with somebody else's help (to explain the second
- handwriting) -- perhaps Dee himself, although he's always struck me as a
- credulous dupe of Kelley rather than a co-conspirator (cf the Angelic
- language stuff).
-
- The best source I know for the Voynich is Mary D'Imperio's monograph
- "The Voynich Manuscript: An Elegant Enigma", which is available from
- Aegean Park Press.
-
- --
- Jim Gillogly
- jim@rand.org
-
-
- Here's an update on the Voynich manuscript. This will concentrate on
- sources for information on the Voynich; later I will write a survey of
- what I have found out so far. I begin with some references to the
- case, kindly sent to me by Karl Kluge (the first three) and Micheal Roe
- <M.Roe@cs.ucl.ac.uk> (the rest).
-
- TITLE Thirty-five manuscripts : including the St. Blasien psalter, the
- Llangattock hours, the Gotha missal, the Roger Bacon (Voynich)
- cipher ms.
- Catalogue ; 100
- 35 manuscripts.
- CITATION New York, N.Y. : H.P. Kraus, [1962] 86 p., lxvii p. of plates, [1]
- leaf of plates : ill. (some col.), facsims. ; 36 cm.
- NOTES "30 years, 1932-1962" ([28] p.) in pocket. Includes indexes.
- SUBJECT Manuscripts Catalogs.
- Illumination of books and manuscripts Catalogs.
-
- AUTHOR Brumbaugh, Robert Sherrick, 1918-
- TITLE The most mysterious manuscript : the Voynich "Roger Bacon" cipher
- manuscript / edited by Robert S. Brumbaugh.
- CITATION Carbondale : Southern Illinois University Press, c1978. xii, 175 p.
- : ill. ; 22 cm.
- SUBJECT Bacon, Roger, 1214?-1294.
- Ciphers.
-
- AUTHOR D'Imperio, M. E.
- TITLE The Voynich manuscript : an elegant enigma / M. E. D'Imperio.
- CITATION Fort George E. Mead, Md. : National Security Agency/Central Security
- Service, 1978. ix, 140 p. : ill. ; 27 cm.
- NOTES Includes index. Bibliography: p. 124-131.
- SUBJECT Voynich manuscript. [NOTE: see alternate publisher below!]
-
- @book{Bennett76,
- author = "Bennett, William Ralph",
- title = "Scientific and Engineering Problem Solving with the Computer",
- address = "Englewood Cliffs, NJ",
- publisher = "Prentice-Hall",
- year = 1976}
-
- @book{dImperio78,
- author = "D'Imperio, M E",
- title = "The Voynich manuscript: An Elegant Enigma",
- publisher= "Aegean Park Press",
- year = 1978}
-
- @article{Friedman62,
- author = "Friedman, Elizebeth Smith",
- title = "``The Most Mysterious Manuscript'' Still Mysterious",
- booktitle = "Washington Post",
- month = "August 5",
- notes = "Section E",
- pages = "1,5",
- year = 1962}
-
- @book{Kahn67,
- author = "Kahn, David",
- title = "The Codebreakers",
- publisher = "Macmillan",
- year = "1967"}
-
- @article{Manly31,
- author = "Manly, John Matthews",
- title = "Roger Bacon and the Voynich MS",
- boooktitle = "Speculum VI",
- pages = "345--91",
- year = 1931}
-
- @article{ONeill44,
- author = "O'Neill, Hugh",
- title = "Botanical Remarks on the Voynich MS",
- journal = "Speculum XIX",
- pages = "p.126",
- year = 1944}
-
- @book{Poundstone88,
- author = "Poundstone, W.",
- title = "Labyrinths of Reason",
- publisher = "Doubleday",
- address = "New York",
- month = "November",
- year = 1988}
-
- @article{Zimanski70,
- author = "Zimanski, C.",
- title = "William Friedman and the Voynich Manuscript",
- journal = "Philological Quarterly",
- year = "1970"}
-
- @article{Guy91b,
- author = "Guy, J. B. M.",
- title = "Statistical Properties of Two Folios of the Voynich Manuscript",
- journal = "Cryptologia",
- volume = "XV",
- number = "4",
- pages = "pp. 207--218",
- month = "July",
- year = 1991}
-
- @article{Guy91a,
- author = "Guy, J. B. M.",
- title = "Letter to the Editor Re Voynich Manuscript",
- journal = "Cryptologia",
- volume = "XV",
- number = "3",
- pages = "pp. 161--166",
- year = 1991}
-
- This is by no means a complete list. It doesn't include Newbold's
- (largely discredited) work, nor work by Feely and Stong.
- In addition, there is the proposed decryption by Leo Levitov (also
- largely discredited):
-
- "Solution of the Voynich Manuscript: A Liturgical Manual for the
- Endura Rite of the Cathari Heresy, the Cult of Isis_, available from
- Aegean Park Press, P. O. Box 2837, Laguna Hills CA 92654-0837."
-
- According to Earl Boebert, this book is reviewed in
- Cryptologia XII, 1 (January 1988). I should add that Brumbaugh's book
- above gives a third, also largely discredited, decryption of the Voynich.
-
- According to smb@att.ulysses.com, Aegean Park Press does mail-order
- business and can be reached at the above address or at 714-586-8811
- (an answering machine).
-
- Micheal Roe has explained how one get microfilms of the whole
- manuscript:
-
- "The Beinecke Rare Book Library, Yale University sells a microfilm of the
- manuscript. Their catalog number for the original is MS 408, ``The Voynich
- `Roger Bacon' Cipher MS''. You should write to them.
-
- The British Library [sic - should be Museum] has a photocopy of the MS
- donated to them by John Manly circa 1931. They apparently lost it until
- 12 March 1947, when it was entered in the catalogue (without
- cross-references under Voynich, Manly, Roger Bacon or any other useful
- keywords...)
-
- It appears as ``MS Facs 461: Positive rotographs of a Cipher MS (folios 1-56)
- acquired in 1912 by Wilfred M. Voynich in Southern Europe.'
- Correspondance between Newbold, Manly and various British Museum experts
- appears under ``MS Facs 439: Leaves of the Voynich MS, alleged to be in
- Roger Bacon's cypher, with correspondence and other pertinent material''
- See John Manly's 1931 article in Speculum and Newbold's book for what the
- correspondance was about! There are also a number of press cuttings.
-
- Both of these in are in the manuscript collection, for which special
- permission is needed in addition to a normal British Library reader's pass."
-
- Also, Jim Gillogly has been extremely kind in making available
- part of the manuscript that was transcribed and keyed in by Mary
- D'Imperio (see above), using Prescott Currier's notation. It appears to
- consist of 166 of the total 232 pages. I hope to do some statistical
- studies on this, and I encourage others to do the same and let me know
- what they find! As Jim notes, the file is pub/jim/voynich.tar.Z and is
- available by anonymous ftp at rand.org. I've had a little trouble with
- this file at page 165, where I read "1650voynich 664" etc., with page
- 166 missing. If anyone else notes this let Jim or I know.
-
- Jim says he has confirmed by correlations between digraph matrices the
- discovery by Prescott Crurrier that the manuscript is written in two
- visibly distinct hands. These are marked "A" and "B" in the file
- voynich.tar.Z.
-
- Because of the possibility that the Voynich is nonsense, it would be
- interesting to compare the Voynich to the Codex Seraphinianus, which
- Kevin McCarty kindly reminded me of. He writes:
-
- "This is very odd. I know nothing of the Voynich manuscript, but
- I know of something which sounds very much like it and was created
- by an Italian artist, who it now seems was probably influenced
- by this work. It a book titled "Codex Seraphinianus", written in
- a very strange script. The title page contains only the book's title
- and the publisher's name: Abbeville Press, New York. The only clues
- in English (in *any* recognizable language) are some blurbs on the
- dust jacket that identify it as a modern work of art, and the copyright
- notice, in fine print, which reads
-
- "Library of Congress Cataloging in Publication Data
-
- Serafini, Luigi.
- Codex Seraphinianus.
-
- 1. Imaginary Languages. 2. Imaginary societies.
- 3. Encyclopedias and Dictionaries-- Miscellanea.
-
- I. Title.
- PN6381.S4 1983 818'.5407 83.-7076
- ISBN 0-89659-428-9
-
- First American Edition, 1983.
- Copyright (c) 1981 by Franco Maria Ricci. All rights reserved
- by Abbeville Press. No part of this book may be reproduced...
- without permission in writing from the publisher. Inquiries should
- be addressed to Abbeville Press, Inc., 505 Park Avenue, New York
- 10022. Printed and bound in Italy."
-
- The book is remarkable and bizarre. It *looks* like an encyclopedia
- for an imaginary world. Page after page of beautiful pictures
- of imaginary flora and fauna, with annotations and captions in
- a completely strange script. Machines, architecture, umm, 'situations',
- arcane diagrams, implements, an archeologist pointing at a Rosetta stone
- (with phony hieroglyphics), an article on penmanship (with unorthodox
- pens), and much more, finally ending with a brief index.
-
- The script in this work looks vaguely similar to the Voynich orthography
- shown in Poundstone's book (I just compared them); the alphabets
- look quite similar, but the Codex script is more cursive and less
- bookish than Voynich. It runs to about 200 pages, and probably
- ought to provide someone two things:
- - a possible explanation of what the Voynich manuscript is
- (a highly imaginative work of art)
- - a textual work which looks like it was inspired by it and might
- provide an interesting comparison for statistical study."
-
- I suppose it would be too much to hope that someone has already
- transcribed parts of the Codex, but nonetheless, if anyone has any in
- electronic form, I would love to have a copy for comparative statistics.
-
- Jacques Guy kindly summarized his analysis (in Cryptologia, see above)
- of the Voynich as follows:
-
- "I transcribed the two folios in Bennett's book and submitted them to
- letter-frequency counts, distinguishing word-initial, word-medial,
- word-final, isolated, line-initial, and line-final positions. I also
- submitted that transcription to Sukhotin's algorithm which, given a text
- written in an alphabetical system, identifies which symbols are vowels and
- which are consonants. The letter transcribed CT in Bennett's system came
- out as a consonant, the one transcribed CC as vowel. Now it so happens
- that CT is exactly the shape of the letter "t" in the Beneventan script
- (used in medieval Spain and Northern Italy), and CC is exactly the shape
- of "a" in that same script. I concluded that the author had a knowledge
- of that script, and that the values of CT and CC probably were "t" and
- "a". There's a lot more, but more shaky."
-
- By popular demand I've put a machine-readable copy of the Voynich Manuscript
- up for anonymous ftp:
-
- Host: rand.org
- File: pub/jim/voynich.tar.Z
-
- It uses Prescott Currier's notation, and was transcribed by Mary D'Imperio.
- If you use it in any analysis, be sure to give credit to D'Imperio, who put
- in a lot of effort to get it right.
-
- --
- Jim Gillogly
- jim@rand.org
-
-
-
- This post is essentially a summary of the fruit of a short research
- quest at the local library.
-
- Brief description of the Voynich manuscript:
-
- The Voynich manuscript was bought (in about 1586) by the Holy Roman
- Emperor Rudolf II. He believed it to be the work of Roger Bacon
- an english 13th century philosopher. The manuscript consisted of about
- 200 pages with many illustrations. It is believed that the manuscript
- contains some secret scientific or magical knowledge since it is entirely
- written in secret writing (presumably in cipher).
-
- The Voynich Manuscript is often abbreviated "Voynich MS" in all of the
- books I have read on Voynich. This is done without explanation. I
- suppose it is just a convention started by the founding analysts of
- the manuscript to call it that.
-
- William R. Newbold, one of the original analysts of the Voynich MS after
- Voynich, claims to have arrived at a partial decipherment of the entire
- manuscript. His book The Cipher of Roger Bacon [2] contains a history
- of the unravelment of the cipher *and* keys to the cipher itself. As well
- as translations of several pages of the manuscript.
-
- Newbold derives his decipherment rules through a study of the medeival
- mind (which he is a leading scholar in) as well as the other writings
- of Roger Bacon. Says Newbold, ciphers in Roger Bacon's writings are not
- new, as Bacon discusses in other works the need for monks to use
- encipherment to protect their knowlege.
-
- Newbold includes many partial decipherments from the Voynich MS but most of
- them are presented in Latin only.
-
- Newbolds deciphering rules (from The Cipher of Roger Bacon [1])
- ---------------------------------------------------------------
- 1. Syllabification: [double all but the first and last letters of each
- word, and divide the product into biliteral groups or symbols.]
- 2. Translation: [translate these symbols into the alphabetic values]
- 3. Reversion: [change the alphabetic values to the phonetic values, by use
- of the reversion alphabet]
- 4. Recomposition: [ rearrange the letters in order, and thus recompose the
- true text].
-
- The text I copied this from failed to note step 0 which was:
- 0. Ignore. [ignore the actual shape of every symbol and analyze only the
- (random?) properties of the direction of swirl and crosshatch patterns
- of the characters when viewed under a microscope. 14 distinct contruction
- patterns can be identified among the (much larger) set of symbols]
-
- John M. Manly in The Most Mysterious Manuscript [3], suggests that Newbold's
- method of decipherment is totally invalid. Manly goes on to show that it
- is not difficult to obtain *ANY DESIRABLE* message from the Voynich MS
- using Newbold's rules. He shows that after fifteen minutes deciphering
- a short sequence of letters he arrives at the plaintext message
- "Paris is lured into loving vestals..."
- and quips that he will furnish a continuation of the translation upon
- request!
-
- The reason I have spent so much time explaining Newbold's method is that
- Newbold presents the most convincing argument for how he arrived at his
- conclusions. Notwithstanding the fact that he invented the oija board of
- deciphering systems.
-
- Joseph Martin Feely, in his book on the Voynich MS [2] , claims to have
- found the key to deciphering at least one page of the Voynich MS. His entire
- book on the topic of the Voynich manuscript is devoted to the deciphering of
- the single page 78. Feely presents full tables of translation of the page 78
- from its written form into latin (and english). It seems that Feely was using
- the exhaustive analysis method to determine the key.
-
- Feely suggests the following translation of (the first fiew lines of) page
- 78 of the Voynich MS:
-
- "the combined stream when well humidified, ramifies; afterward it is broken
- down smaller; afterward, at a distance, into the fore-bladder it comes [1].
- Then vesselled, it is after-a-while ruminated: well humidified it is
- clothed with veinlets [2]. Thence after-a-bit they move down; tiny
- teats they provide (or live upon) in the outpimpling of the veinlets.
- They are impermiated; are thrown down below; they are ruminated; they are
- feminized with the tiny teats. .... "
-
- ... and so on for three more pages of "english plaintext".
-
- The descriptions by Feely say that this text is accompanied in the Voynich MS
- by an illustration that (he says) is unmistakably the internal female
- reproductive organs (I saw the plate myself and they DO look like fallopian
- tubes *AFTER* I read the explanation).
-
- The most informative work that I found (I feel) was "The Most Mysterious
- Manuscript". Of the five books on Voynich that I found, this was the only
- one that didn't claim to have found the key but was, rather, a collection
- of essays on the history of the Voynich MS and criticisms of various attempts
- by earlier scientists. It was also the *latest* book that I was able to
- consult, being published in 1978.
-
- My impression from the black and white plates of the Voynich MS I've seen, are
- that the illustrations are very weird when compared to other 'illuminated'
- manuscripts of this time. Particularly I would say that there is emphasis
- on the female nude that is unusual for the art of this period. I can't say
- that I myself believe the images to have ANYTHING to do with the text.
- My own conjecture is that the manuscript is a one-way encipherment. A
- cipher so clever that the inventor didn't even think of how it could be
- deciphered. Sorta like an /etc/passwd file.
-
- Bibliography
- ------------
- 1. William R. Newbold. _The Cipher of Roger Bacon_Roland G Kent, ed.
- University of Pennsylvania Press, 1928.
- 2. Joseph Martin Feely. _Roger Bacon's Cipher: The Right Key Found_
- Rochester N.Y.:Joseph Martin Feely, pub., 1943.
- 3. _The Most Mysterious Manuscript_ Robert S. Brumbaugh, ed. Southern Illinois
- Press, 1978
-
-
- Unix filters are so wonderful. Massaging the machine readable file, we find:
-
- 4182 "words", of which 1284 are used more than once, 308 used 8+ times,
- 184 used 15+ times, 23 used 100+ times.
-
- Does this tell us anything about the language (if any) the text is written
- in?
-
- For those who may be interested, here are the 23 words used 100+ times:
- 121 2
- 115 4OFAE
- 114 4OFAM
- 155 4OFAN
- 195 4OFC89
- 162 4OFCC89
- 101 4OFCC9
- 189 89
- 111 8AE
- 492 8AM
- 134 8AN
- 156 8AR
- 248 OE
- 148 OR
- 111 S9
- 251 SC89
- 142 SC9
- 238 SOE
- 150 SOR
- 244 ZC89
- 116 ZC9
- 116 ZOE
-
-
-
- Could someone email the Voynich Ms. ref list that appeared here not
- very long ago? Thanks in advance...
-
- Also... I came across the following ref that is fun(?):
-
- The Voynich manuscript: an elegant enigma / M. E. D'Imperio
- Fort George E. Mead, Md. : National Security Agency(!)
- Central Security Service(?), 1978. ix, 140 p. : ill. ; 27 cm.
-
- The (?!) are mine... Sorry if this was already on the list, but the
- mention of the NSA (and what's the CSS?) made it jump out at me...
-
- --
- Ron Carter | rcarter@nyx.cs.du.edu rcarter GEnie 70707.3047 CIS
- Director | Center for the Study of Creative Intelligence
- Denver, CO | Knowledge is power. Knowledge to the people. Just say know.
-
-
-
- Distribution: na
- Organization: Wetware Diversions, San Francisco
- Keywords:
-
-
- From sci.archaeology:
- >From: jamie@cs.sfu.ca (Jamie Andrews)
- >Date: 16 Nov 91 00:49:08 GMT
- >
- > It seems like the person who would be most likely to solve
- >this Voynich manuscript cipher would have
- >(a) knowledge of the modern techniques for solving more complex
- > ciphers such as Playfairs and Vigineres; and
- >(b) knowledge of the possible contemporary and archaic languages
- > in which the plaintext could have been written.
-
- An extended discussion of the Voynich Manuscript may be found in the
- tape of the same name by Terence McKenna. I'm not sure who is currently
- publishing this particular McKenna tape but probably one of:
- Dolphin Tapes, POB 71, Big Sur, CA 93920
- Sounds True, 1825 Pearl St., Boulder, CO 80302
- Sound Photosynthesis, POB 2111, Mill Valley, CA 94942
-
- The Spring 1988 issue of Gnosis magazine contained an article by McKenna
- giving some background of the Voynich Manuscipt and attempts to decipher
- it, and reviewing Leo Levitov's "Solution of the Voynich Manuscript"
- (published in 1987 by Aegean Park Press, POB 2837 Laguna Hills, CA 92654).
- Levitov's thesis is that the manuscript is the only surviving primary
- document of the Cathar faith (exterminated on the orders of the Pope in
- the Albigensian Crusade in the 1230s) and that it is in fact not
- encrypted material but rather is a highly polyglot form of Medieval
- Flemish with a large number of Old French and Old High German loan
- words, written in a special script.
-
- As far as I know Levitov's there has been no challenge to Levitov's
- claims so far.
-
-
-
- Michael Barlow, who had reviewed Levitov's book in Cryptologia, had sent me
- photocopies of the pages where much of the language was described
- (pp.21-31). I have just found them, and am looking at them now as I am
- typing this. Incidentally, I do not believe this has anything to do with
- cryptology proper, but the decipherment of texts in unknown languages. So
- if you are into cryptography proper, skip this.
-
- Looking at the "Voynich alphabet" pp.25-27, I made a list of the letters of
- the Voynich language as Levitov interprets them, and I added phonetic
- descriptions of the sounds I *think* Levitov meant to describe. Here it is:
-
- Letter# Phonetic Phonetic descriptions
- (IPA) in linguists' jargon: in plain English:
-
- 1 a low open, central unrounded a as in father
- e mid close, front, unrounded ay as in May
- O mid open, back, rounded aw as in law
- or o as in got
- (British
- pronunciation)
-
- 2 s unvoiced dental fricative s as in so
- 3 d voiced dental stop d
- 4 E mid, front, unrounded e as in wet
- 5 f unvoiced labiodental fricative f
- 6 i short, high open, front, i as in dim
- unrounded
- 7 i: long, high, front, unrounded ea as in weak
-
- 8 i:E (?) I can't make head nor tail of Levitov's
- explanations. Probably like "ei" in "weird"
- dragging along the "e": "weeeird"! (British
- pronunciation, with a silent "r")
- 9 C unvoiced palatal fricative ch in German ich
- 10 k unvoived velar stop k
-
- 11 l lateral, can't be more precise from
- description, probably like l in "loony"
-
- 12 m voiced bilabial nasal m
- 13 n voiced dental nasal n
- 14 r (?) cannot tell precisely from Scottish r?
- description Dutch r?
- 15 t no description; dental stop? t
- 16 t another form for #15 t
- 17 T (?) no description th as in this?
- th as in thick?
- 18 TE (?) again, no description
- or ET (?)
- 19 v voiced labiodental fricative v as in rave
- 20 v ditto, same as #19 ditto
-
- (By now, you will have guessed what my conclusion about Levitov's
- decipherment was)
-
- In the column headed "Phonetic (IPA)" I have used capital letters for lack
- of the special international phonetic symbols:
-
- E for the Greek letter "epsilon"
- O for the letter that looks like a mirror-image of "c"
- C for c-cedilla
- T for the Greek letter "theta"
-
- The colon (:) means that the sound represented by the preceding letter is
- long, e.g. "i:" is a long "i".
-
- The rest, #21 to 25, are not "letters" proper, but represent groups
- of two or more letters, just like #18 does. They are:
-
- 21 av
- 22a Ev
- 22b vE
- 23 CET
- 24 kET
- 25 sET
-
- That gives us a language with 6 vowels: a (#1), e (#1 again), O (#1 again),
- E (#4), i (#6), and i: (#7). Letter #8 is not a vowel, but a combination
- of two vowels: i: (#7) and probably E (#4). Levitov writes that the
- language is derived from Dutch. If so, it has lost the "oo" sound (English
- spelling; "oe" in Dutch spelling), and the three front rounded vowels of
- Dutch: u as in U ("you", polite), eu as in deur ("door"), u as in vlug
- ("quick"). Note that out of six vowels, three are confused under the same
- letter (#1), even though they sound very different from one another: a, e,
- O. Just imagine that you had no way of distinguishing between "last",
- "lest" and "lost" when writing in English, and you'll have a fair idea of
- the consequences.
-
- Let us look at the consonants now. I will put them in a matrix, with the
- points of articulation in one dimension, and the manner of articulation in
- the other (it's all standard procedure when analyzing a language). Brackets
- around a letter will mean that I could not tell where to place it exactly,
- and just took a guess.
-
- labial dental palatal velar
- nasal m n
- voiced stop d
- unvoiced stop t k
- voiced fricative v (T)
- unvoiced fricative f s C
- lateral l
- trill (?) (r)
-
- Note that there are only twelve consonant sounds. That is unheard of for a
- European language. No European language has so few consonant sounds.
- Spanish, which has very few sounds (only five vowels), has seventeen
- distinct consonants sounds, plus two semi-consonants. Dutch has from 18 to
- 20 consonants (depending on speakers, and how you analyze the sounds.
- Warning: I just counted them on the back of an envelope; I might have
- missed one or two). What is also extraordinary in Levitov's language is
- that it lacks a "g", and *BOTH* "b" and "p". I cannot think of one single
- language in the world that lacks both "b" and "p". Levitov also says that
- "m" occurs only word-finally, never at the beginning, nor in the middle of
- a word. That's true: the letter he says is an "m" is always word-final in
- the reproductions I have seen of the Voynich MS. But no language I know of
- behaves like that. All have an "m" (except one American Indian language,
- which is very famous for that, and the name of which escapes me right now),
- but, if there is a position where "m" never appears in some languages, that
- position is word-finally. Exactly the reverse of Levitov's language.
-
- What does Levitov say about the origin of the language?
-
- "The language was very much standardized. It was an application of a
- polyglot oral tongue into a literary language which would be understandable
- to people who did not understand Latin and to whom this language could be
- read."
-
- At first reading, I would dismiss it all as nonsense: "polyglot oral
- tongue" means nothing in linguistics terms. But Levitov is a medical
- doctor, so allowances must be made. The best meaning I can read into
- "polyglot oral tongue" is "a language that had never been written before
- and which had taken words from many different languages". That is perfectly
- reasonable: English for one, has done that. Half its vocabulary is Norman
- French, and some of the commonest words have non-Anglo-Saxon origins.
- "Sky", for instance, is a Danish word. So far, so good.
-
- Levitov continues: "The Voynich is actually a simple language because it
- follows set rules and has a very limited vocabulary.... There is a
- deliberate duality and plurality of words in the Voynich and much use of
- apostrophism".
-
- By "duality and plurality of words" Levitov means that the words are highly
- ambiguous, most words having two or more different meanings. I can only
- guess at what he means by apostrophism: running words together, leaving
- bits out, as we do in English: can not --> cannot --> can't, is not -->
- ain't.
-
- Time for a tutorial in the Voynich language as I could piece it together
- from Levitov's description. Because, according to Levitov, letter #1
- represent 3 vowels sounds, I will represent it by just "a", but remember:
- it can be pronounced a, e, or o. But I will distinguish, as does Levitov,
- between the two letters which he says were both pronounced "v", using "v"
- for letter #20 and "w" for letter #21.
-
- Some vocabulary now. Some verbs first, which Levitov gives in the
- infinitive. In the Voynich language the infinitive of verbs ends in -en,
- just like in Dutch and in German. I have removed that grammatical ending in
- the list which follows, and given probable etymologies in parentheses
- (Levitov gives doesn't give any):
-
- ad = to aid, help ("aid")
- ak = to ache, pain ("ache")
- al = to ail ("ail")
- and = to undergo the "Endura" rite ("End[ura]", probably)
- d = to die ("d[ie]")
- fad = to be for help (from f= for and ad=aid)
- fal = to fail ("fail")
- fil = to be for illness (from: f=for and il=ill)
- il = to be ill ("ill")
- k = to understand ("ken", Dutch and German "kennen" meaning "to know")
- l = to lie deathly ill, in extremis ("lie", "lay")
- s = to see ("see", Dutch "zien")
- t = to do, treat (German "tun" = to do)
- v = to will ("will" or Latin "volo" perhaps)
- vid = to be with death (from vi=with and d=die)
- vil = to want, wish, desire (German "willen")
- vis = to know ("wit", German "wissen", Dutch "weten")
- vit = to know (ditto)
- viT = to use (no idea, Latin "uti" perhaps?)
- vi = to be the way (Latin "via")
- eC = to be each ("each")
- ai:a = to eye, look at ("eye", "oog" in Dutch)
- en = to do (no idea)
- Example given by Levitov: enden "to do to death" made up of "en"
- (to do), "d" (to die) and "en" (infinitive ending). Well, to me,
- that's doing it the hard way. What's wrong with just "enden" = to
- end (German "enden", too!)
-
- More vocabulary:
-
- em = he or they (masculine) ("him")
- er = her or they (feminine) ("her")
- eT = it or they ("it" or perhaps "they" or Dutch "het")
- an = one ("one", Dutch "een")
-
- "There are no declensions of nouns or conjugation of verbs. Only the
- present tense is used" says Levitov.
-
- Examples:
-
- den = to die (infinitive) (d = die, -en = infinitive)
- deT = it/they die (d = die, eT = it/they)
- diteT = it does die (d = die, t = do, eT = it/they, with an "i" added to
- make it easier to pronounce, which is quite common and natural
- in languages)
-
- But Levitov contradicts himself immediately, giving another tense (known
- as present progressive in English grammar):
-
- dieT = it is dying
-
- But I may be unfair there, perhaps it is a compound: d = die, i = is
- ...-ing, eT = it/they.
-
- Plurals are formed by suffixing "s" in one part of the MS, "eT" in another:
- "ans" or "aneT" = ones.
-
- More:
-
- wians = we ones (wi = we, wie in Dutch, an = one, s = plural)
- vian = one way (vi = way, an = one)
- wia = one who (wi = who, a = one)
- va = one will (v = will, a = one)
- wa = who
- wi = who
- wieT = who, it (wi = who, eT = it)
- witeT = who does it (wi = who, t = do, eT = it/they)
- weT = who it is (wi = who, eT = it, then loss of "i", giving "weT")
- ker = she understands (k = understand, er =she)
-
- At this stage I would like to comment that we are here in the presence of a
- Germanic language which behaves very, very strangely in the way of the
- meanings of its compound words. For instance, "viden" (to be with death) is
- made up of the words for "with", "die" and the infinitive suffix. I am sure
- that Levitov here was thinking of a construction like German "mitkommen"
- which means "to come along" (to "withcome"). I suppose I could say "Bitte,
- sterben Sie mit" on the same model as "Bitte, kommen Sie mit" ("Come with
- me/us, please), thereby making up a verb "mitsterben", but that would mean
- "to die together with someone else", not "to be with death".
-
- Let us see how Levitov translates a whole sentence. Since he does not
- explain how he breaks up those compound words I have tried to do it using
- the vocabulary and grammar he provides in those pages. My tentative
- explanations are in parenthesis.
-
- TanvieT faditeT wan aTviteT anTviteT atwiteT aneT
-
- TanvieT = the one way (T = the (?), an = one, vi =way, eT = it)
- faditeT = doing for help (f = for, ad = aid, i = -ing, t = do, eT = it)
- wan = person (wi/wa = who, an = one)
- aTviteT = one that one knows (a = one, T = that, vit = know, eT = it.
- Here, Levitov adds one extra letter which is not in the text,
- getting "aTaviteT", which provide the second "one" of his
- translation)
- anTviteT = one that knows (an =one, T = that, vit = know, eT = it)
- atwiteT = one treats one who does it (a = one, t = do, wi = who,
- t = do, eT = it. Literally: "one does [one] who does it".
- The first "do" is translated as "treat", the second "one" is
- added in by Levitov: he added one letter, which gives him
- "atawiteT")
- aneT = ones (an = one, -eT = the plural ending)
-
- Levitov's translation of the above in better English: "the one way for
- helping a person who needs it, is to know one of the ones who do treat
- one".
-
- Need I say more? Does anyone still believe that Levitov's translations are
- worth anything?
-
- As an exercise, here is the last sentence on p.31, with its word-for-word
- translation by Levitov. I leave you to work it out, and to figure out what
- it might possibly mean. Good luck!
-
- tvieT nwn anvit fadan van aleC
-
- tvieT = do the ways
- nwn = not who does (but Levitov adds a letter to make it "nwen")
- anvit = one knows
- fadan = one for help
- van = one will
- aleC = each ail
-
- ==> cryptology/swiss.colony.p <==
- What are the 1987 Swiss Colony ciphers?
-
- ==> cryptology/swiss.colony.s <==
- Did anyone solve the 1987 'Crypto-gift' contest that was run by
- Swiss Colony? My friend and I worked on it for 4 months, but
- didn't get anywhere. My friend solved the 1986 puzzle in
- about a week and won $1000. I fear that we missed some clue that
- makes it incredibly easy to solve. I'm including the code, clues
- and a few notes for those of you so inclined to give it a shot.
-
- 197,333,318,511,824,
- 864,864,457,197,333,
- 824,769,372,769,864,
- 865,457,153,824,511,223,845,318,
- 489,953,234,769,703,489,845,703,
- 372,216,457,509,333,153,845,333,
- 511,864,621,611,769,707,153,333,
- 703,197,845,769,372,621,223,333,
- 197,845,489,953,223,769,216,223,
- 769,769,457,153,824,511,372,223,
- 769,824,824,216,865,845,153,769,
- 333,704,511,457,153,333,824,333,
- 953,372,621,234,953,234,865,703,
- 318,223,333,489,944,153,824,769,
- 318,457,234,845,318,223,372,769,
- 216,894,153,333,511,611,
- 769,704,511,153,372,621,
- 197,894,894,153,333,953,
- 234,845,318,223
-
- CHRIS IS BACK WITH GOLD FOR YOU
- HIS RHYMES CONTAIN THE SECRET.
- YOU SCOUTS WHO'VE EARNED YOUR MERIT BADGE
- WILL QUICKLY LEARN TO READ IT.
- SO WHEN YOUR CHRISTMAS HAM'S ALL GONE
- AND YOU'RE READY FOR THE TUSSLE,
- BALL UP YOUR HAND INTO A FIST
- AND SHOW OUR MOUSE YOUR MUSCLE.
- PLEASE READ THESE CLUES WE LEAVE TO YOU
- BOTH FINE ONES AND THE COARSE;
- IF CARE IS USED TO HEED THEM ALL
- YOU'LL SUFFER NO REMORSE.
-
- Notes:
- The puzzle comes as a jigsaw that when assembled has the list of
- numbers. They are arranged as indicated on the puzzle, with commas.
- The lower right corner has a drawing of 'Secret Agent Chris Mouse'.
- He holds a box under his arm which looks like the box
- the puzzle comes in. The upper left
- corner has the words 'NEW 1987 $50,000 Puzzle'. The lower
- left corner is empty. The clues are printed on the
- entry form in upper case, with the punctuation as shown.
-
- Ed Rupp
- ...!ut-sally!oakhill!ed
- Motorola, Inc., Austin Tx.
-
-
-
- ==> decision/allais.p <==
- The Allais Paradox involves the choice between two alternatives:
-
- A. 89% chance of an unknown amount
- 10% chance of $1 million
- 1% chance of $1 million
- B. 89% chance of an unknown amount (the same amount as in A)
- 10% chance of $2.5 million
- 1% chance of nothing
-
- What is the rational choice? Does this choice remain the same if the
- unknown amount is $1 million? If it is nothing?
-
- ==> decision/allais.s <==
- This is "Allais' Paradox".
-
- Which choice is rational depends upon the subjective value of money.
- Many people are risk averse, and prefer the better chance of $1
- million of option A. This choice is firm when the unknown amount is
- $1 million, but seems to waver as the amount falls to nothing. In the
- latter case, the risk averse person favors B because there is not much
- difference between 10% and 11%, but there is a big difference between
- $1 million and $2.5 million.
-
- Thus the choice between A and B depends upon the unknown amount, even
- though it is the same unknown amount independent of the choice. This
- violates the "independence axiom" that rational choice between two
- alternatives should depend only upon how those two alternatives
- differ.
-
- However, if the amounts involved in the problem are reduced to tens of
- dollars instead of millions of dollars, people's behavior tends to
- fall back in line with the axioms of rational choice. People tend to
- choose option B regardless of the unknown amount. Perhaps when
- presented with such huge numbers, people begin to calculate
- qualitatively. For example, if the unknown amount is $1 million the
- options are:
-
- A. a fortune, guaranteed
- B. a fortune, almost guaranteed
- a tiny chance of nothing
-
- Then the choice of A is rational. However, if the unknown amount is
- nothing, the options are:
-
- A. small chance of a fortune ($1 million)
- large chance of nothing
- B. small chance of a larger fortune ($2.5 million)
- large chance of nothing
-
- In this case, the choice of B is rational. The Allais Paradox then
- results from the limited ability to rationally calculate with such
- unusual quantities. The brain is not a calculator and rational
- calculations may rely on things like training, experience, and
- analogy, none of which would be help in this case. This hypothesis
- could be tested by studying the correlation between paradoxical
- behavior and "unusualness" of the amounts involved.
-
- If this explanation is correct, then the Paradox amounts to little
- more than the observation that the brain is an imperfect rational
- engine.
-
- ==> decision/division.p <==
- N-Person Fair Division
-
- If two people want to divide a pie but do not trust each other, they can
- still ensure that each gets a fair share by using the technique that one
- person cuts and the other person chooses. Generalize this technique
- to more than two people. Take care to ensure that no one can be cheated
- by a coalition of the others.
-
-
- ==> decision/division.s <==
- N-Person Fair Division
-
- Number the people from 1 to N. Person 1 cuts off a piece of the pie.
- Person 2 can either diminish the size of the cut off piece or pass.
- The same for persons 3 through N. The last person to touch the piece
- must take it and is removed from the process. Repeat this procedure
- with the remaining N - 1 people, until everyone has a piece.
- (cf. Luce and Raiffa, "Games and Decisions", Wiley, 1957, p. 366)
-
- There is a cute result in combinatorics called the Marriage Theorem.
- A village has n men and n women, such that for all 0 < k <= n and for any
- set of k men there are at least k women, each of whom is in love with at least
- one of the k men. All of the men are in love with all of the women :-}.
- The theorem asserts that there is a way to arrange the village into n
- monogamous couplings.
-
- The Marriage Theorem can be applied to the Fair Pie-Cutting Problem.
-
- One player cuts the pie into n pieces. Each of the players labels
- some non-null subset of the pieces as acceptable to him. For reasons
- given below he should "accept" each piece of size > 1/n, not just the
- best piece(s). The pie-cutter is required to "accept" all of the pieces.
-
- Given a set S of players let S' denote the set of pie-pieces
- acceptable to at least one player in S. Let t be the size of the largest
- set (T) of players satisfying |T| > |T'|. If there is no such set, the
- Marriage Theorem can be applied directly. Since the pie-cutter accepts
- every piece we know that t < n.
-
- Choose |T| - |T'| pieces at random from outside T', glue them
- together with the pieces in T' and let the players in T repeat the game
- with this smaller (t/n)-size pie. This is fair since they all rejected
- the other n-t pieces, so they believe this pie is larger than t/n.
-
- The remaining n-t players can each be assigned one of the remaining
- n-t pie-pieces without further ado due to the Marriage Theorem. (Otherwise
- the set T above was not maximal.)
-
- ==> decision/dowry.p <==
- Sultan's Dowry
-
- A sultan has granted a commoner a chance to marry one of his hundred
- daughters. The commoner will be presented the daughters one at a time.
- When a daughter is presented, the commoner will be told the daughter's
- dowry. The commoner has only one chance to accept or reject each
- daughter; he cannot return to a previously rejected daughter.
- The sultan's catch is that the commoner may only marry the daughter with
- the highest dowry. What is the commoner's best strategy assuming
- he knows nothing about the distribution of dowries?
-
-
- ==> decision/dowry.s <==
- Solution
-
- Since the commoner knows nothing about the distribution of the dowries,
- the best strategy is to wait until a certain number of daughters have
- been presented then pick the highest dowry thereafter. The exact number to
- skip is determined by the condition that the odds that the highest dowry
- has already been seen is just greater than the odds that it remains to be
- seen AND THAT IF IT IS SEEN IT WILL BE PICKED. This amounts to finding the
- smallest x such that:
- x/n > x/n * (1/(x+1) + ... + 1/(n-1)).
- Working out the math for n=100 and calculating the probability gives:
- The commoner should wait until he has seen 37 of the daughters,
- then pick the first daughter with a dowry that is bigger than any
- preceding dowry. With this strategy, his odds of choosing the daughter
- with the highest dowry are surprisingly high: about 37%.
- (cf. F. Mosteller, "Fifty Challenging Problems in Probability with Solutions",
- Addison-Wesley, 1965, #47; "Mathematical Plums", edited by Ross Honsberger,
- pp. 104-110)
-
- ==> decision/envelope.p <==
- Someone has prepared two envelopes containing money. One contains twice as
- much money as the other. You have decided to pick one envelope, but then the
- following argument occurs to you: Suppose my chosen envelope contains $X,
- then the other envelope either contains $X/2 or $2X. Both cases are
- equally likely, so my expectation if I take the other envelope is
- .5 * $X/2 + .5 * $2X = $1.25X, which is higher than my current $X, so I
- should change my mind and take the other envelope. But then I can apply the
- argument all over again. Something is wrong here! Where did I go wrong?
-
- In a variant of this problem, you are allowed to peek into the envelope
- you chose before finally settling on it. Suppose that when you peek you
- see $100. Should you switch now?
-
- ==> decision/envelope.s <==
- Let's follow the argument carefully, substituting real numbers for
- variables, to see where we went wrong. In the following, we will assume
- the envelopes contain $100 and $200. We will consider the two equally
- likely cases separately, then average the results.
-
- First, take the case that X=$100.
-
- "I have $100 in my hand. If I exchange I get $200. The value of the exchange
- is $200. The value from not exchanging is $100. Therefore, I gain $100
- by exchanging."
-
- Second, take the case that X=$200.
-
- "I have $200 in my hand. If I exchange I get $100. The value of the exchange
- is $100. The value from not exchanging is $200. Therefore, I lose $100
- by exchanging."
-
- Now, averaging the two cases, I see that the expected gain is zero.
-
- So where is the slip up? In one case, switching gets X/2 ($100), in the
- other case, switching gets 2X ($200), but X is different in the two
- cases, and I can't simply average the two different X's to get 1.25X.
- I can average the two numbers ($100 and $200) to get $150, the expected
- value of switching, which is also the expected value of not switching,
- but I cannot under any circumstances average X/2 and 2X.
-
- This is a classic case of confusing variables with constants.
-
- OK, so let's consider the case in which I looked into the envelope and
- found that it contained $100. This pins down what X is: a constant.
-
- Now the argument is that the odds of $50 is .5 and the odds of $200
- is .5, so the expected value of switching is $125, so we should switch.
- However, the only way the odds of $50 could be .5 and the odds of $200
- could be .5 is if all integer values are equally likely. But any
- probability distribution that is finite and equal for all integers
- would sum to infinity, not one as it must to be a probability distribution.
- Thus, the assumption of equal likelihood for all integer values is
- self-contradictory, and leads to the invalid proof that you should
- always switch. This is reminiscent of the plethora of proofs that 0=1;
- they always involve some illegitimate assumption, such as the validity
- of division by zero.
-
- Limiting the maximum value in the envelopes removes the self-contradiction
- and the argument for switching. Let's see how this works.
-
- Suppose all amounts up to $1 trillion were equally likely to be
- found in the first envelope, and all amounts beyond that would never
- appear. Then for small amounts one should indeed switch, but not for
- amounts above $500 billion. The strategy of always switching would pay
- off for most reasonable amounts but would lead to disastrous losses for
- large amounts, and the two would balance each other out.
-
- For those who would prefer to see this worked out in detail:
- Assume the smaller envelope is uniform on [$0,$M], for some value
- of $M. What is the expectation value of always switching? A quarter of
- the time $100 >= $M (i.e. 50% chance $X is in [$M/2,$M] and 50% chance
- the larger envelope is chosen). In this case the expected switching
- gain is -$50 (a loss). Thus overall the always switch policy has an
- expected (relative to $100) gain of (3/4)*$50 + (1/4)*(-$50) = $25.
- However the expected absolute gain (in terms of M) is:
- / M
- | g f(g) dg, [ where f(g) = (1/2)*Uniform[0,M)(g) +
- /-M (1/2)*Uniform(-M,0](g). ]
-
- = 0. QED.
-
- OK, so always switching is not the optimal switching strategy. Surely
- there must be some strategy that takes advantage of the fact that we
- looked into the envelope and we know something we did not know before
- we looked.
-
- Well, if we know the maximum value $M that can be in the smaller envelope,
- then the optimal decision criterion is to switch if $100 < $M, otherwise stick.
- The reason for the stick case is straightforward. The reason for the
- switch case is due to the pdf of the smaller envelope being twice as
- high as that of the larger envelope over the range [0,$M). That is, the
- expected gain in switching is (2/3)*$100 + (1/3)*(-$50) = $50.
-
- What if we do not know the maximum value of the pdf? You can exploit
- the "test value" technique to improve your chances. The trick here is
- to pick a test value T. If the amount in the envelope is less than the
- test value, switch; if it is more, do not. This works in that if T happens
- to be in the range [M,2M] you will make the correct decision. Therefore,
- assuming the unknown pdf is uniform on [0,M], you are slightly better off
- with this technique.
-
- Of course, the pdf may not even be uniform, so the "test value" technique
- may not offer much of an advantage. If you are allowed to play the game
- repeatedly, you can estimate the pdf, but that is another story...
-
- ==> decision/exchange.p <==
- At one time, the Mexican and American dollars were devalued by 10 cents on each
- side of the border (i.e. a Mexican dollar was 90 cents in the US, and a US
- dollar was worth 90 cents in Mexico). A man walks into a bar on the American
- side of the border, orders 10 cents worth of beer, and tenders a Mexican dollar
- in change. He then walks across the border to Mexico, orders 10 cents worth of
- beer and tenders a US dollar in change. He continues this throughout the day,
- and ends up dead drunk with the original dollar in his pocket.
-
- Who pays for the drinks?
-
- ==> decision/exchange.s <==
- The man paid for all the drinks. But, you say, he ended up with the same
- amount of money that he started with! However, as he transported Mexican
- dollars into Mexico and US dollars into the US, he performed "economic work"
- by moving the currency to a location where it was in greater demand (and thus
- valued higher). The earnings from this work were spent on the drinks.
-
- Note that he can only continue to do this until the Mexican bar runs out
- of US dollars, or the US bar runs out of Mexican dollars, i.e., until
- he runs out of "work" to do.
-
- ==> decision/newcomb.p <==
- Newcomb's Problem
-
- A being put one thousand dollars in box A and either zero or one million
- dollars in box B and presents you with two choices:
- (1) Open box B only.
- (2) Open both box A and B.
- The being put money in box B only if it predicted you will choose option (1).
- The being put nothing in box B if it predicted you will do anything other than
- choose option (1) (including choosing option (2), flipping a coin, etc.).
-
- Assuming that you have never known the being to be wrong in predicting your
- actions, which option should you choose to maximize the amount of money you
- get?
-
-
- ==> decision/newcomb.s <==
- This is "Newcomb's Paradox".
-
- You are presented with two boxes: one certainly contains $1000 and the
- other might contain $1 million. You can either take one box or both.
- You cannot change what is in the boxes. Therefore, to maximize your
- gain you should take both boxes.
-
- However, it might be argued that you can change the probability that
- the $1 million is there. Since there is no way to change whether the
- million is in the box or not, what does it mean that you can change
- the probability that the million is in the box? It means that your
- choice is correlated with the state of the box.
-
- Events which proceed from a common cause are correlated. My mental
- states lead to my choice and, very probably, to the state of the box.
- Therefore my choice and the state of the box are highly correlated.
- In this sense, my choice changes the "probability" that the money is
- in the box. However, since your choice cannot change the state of the
- box, this correlation is irrelevant.
-
- The following argument might be made: your expected gain if you take
- both boxes is (nearly) $1000, whereas your expected gain if you take
- one box is (nearly) $1 million, therefore you should take one box.
- However, this argument is fallacious. In order to compute the
- expected gain, one would use the formulas:
-
- E(take one) = $0 * P(predict take both | take one) +
- $1,000,000 * P(predict take one | take one)
- E(take both) = $1,000 * P(predict take both | take both) +
- $1,001,000 * P(predict take one | take both)
-
- While you are given that P(do X | predict X) is high, it is not given
- that P(predict X | do X) is high. Indeed, specifying that P(predict X
- | do X) is high would be equivalent to specifying that the being could
- use magic (or reverse causality) to fill the boxes. Therefore, the
- expected gain from either action cannot be determined from the
- information given.
-
-
- ==> decision/prisoners.p <==
- Three prisoners on death row are told that one of them has been chosen
- at random for execution the next day, but the other two are to be
- freed. One privately begs the warden to at least tell him the name of
- one other prisoner who will be freed. The warden relents: 'Susie will
- go free.' Horrified, the first prisoner says that because he is now
- one of only two remaining prisoners at risk, his chances of execution
- have risen from one-third to one-half! Should the warden have kept his
- mouth shut?
-
- ==> decision/prisoners.s <==
- Each prisoner had an equal chance of being the one chosen to be
- executed. So we have three cases:
-
- Prisoner executed: A B C
- Probability of this case: 1/3 1/3 1/3
-
- Now, if A is to be executed, the warden will randomly choose either B or C,
- and tell A that name. When B or C is the one to be executed, there is only
- one prisoner other than A who will not be executed, and the warden will always
- give that name. So now we have:
-
- Prisoner executed: A A B C
- Name given to A: B C C B
- Probability: 1/6 1/6 1/3 1/3
-
- We can calculate all this without knowing the warden's answer.
- When he tells us B will not be executed, we eliminate the middle two
- choices above. Now, among the two remaining cases, C is twice
- as likely as A to be the one executed. Thus, the probability that
- A will be executed is still 1/3, and C's chances are 2/3.
-
-