Talk:Phaistos Disc/Archive 1

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Minimum length for a decipherment

This question enters into the general frame established by the mathematician Claude Shannon, in his paper "Communication Theory of Secrecy Systems". Cl. Shannon has established a general formula giving the "Unicity Distance". If the length of a text is shorter than the "Unicity Distance", the text cannot be deciphered, because there is more than one solution. If it is longer, the text may be deciphered when one starts from correct starting hypotheses concerning the language, the code used, etc. As another mathematician, J. Faucounau, wrote, the main factor in this formula is, beside the code, what Cl. Shannon has called "Entropy", which depends upon the language and the text itself. I quote this author : "Le facteur que Cl. Shannon a appelé "Entropy", qui depend du langage et du texte lui-même, est beaucoup plus décisif que la longueur du texte elle-même. Il est ainsi possible de déchiffrer un "texte" d'une longueur aussi courte que 5 ou 6 signes, écrit dans un système de simple substitution (= système du disque de Phaistos), lorsque l'on part, bien entendu, comme le suppose Cl. Shannon, des "bonnes hypothèses". En voici un exemple : Texte : 5-14/11-6-14-11. "Bonnes hypothèses" : a)- un chiffre = une lettre (et réciproquement) b)- le langage est du français c)- il s'agit d'un objet d)- le signe / est un séparateur de mots." If one accepts for the Phaistos Disk a "reasonable figure" for its entropy, the Shannon's Formula leads to a figure of c. 225 signs for the "Unicity Distance", inferior to the real length of the Disk (241 signs). The text of the disk can therefore be deciphered, when one starts from the "good hypotheses". (User 80.90.57.154).

Shannon was talking about cryptography. For a encrypted text he was able to assume that the language is known. But for the disc this is not the case. Therefore his theory is of no use here. Chadwick: "A few decipherments have been proposed using known languages, including a few based upon Greek, despite the obvious improbability of such a solution at this date. What is worse, their authors are rarely aware of what Greek would look like at this period, at least four hundred years before Mycenaean." in Linear B and Releated Scripts p. 61. Kadmos 20:44, 18 October 2005 (UTC)

Shannon was concerned about security, i.e. the possibility of deciphering a coded message IF the decrypter had, by chance or by any other way, found the correct language and the correct encoding code. The fact that these data are unknown in the case of the Phaistos Disk doesn't change the validity of his formula. It is therefore established that the Phaistos Disk can be deciphered when the decipherer uses the "good hypotheses".

As for Chadwick's opinion concerning the implausibility of Greek, it is at the heart of the problem indeed :"Is the so-called Risch-Chadwick Theory right or wrong ?.." The inventor of the "Proto-Ionic Solution", J.Faucounau, and other scholars (e.g. Vl. Georgiev) have shown that it IS wrong (See his book : "Les Proto-Ioniens...", Paris 2001), what is also the proof that the Proto-Ionic Solution is correct. (User 80.90.57.154)

You say it yourself: A deciphering will be only possibly if the correct language is found. Because nobody knows Greek of the time in question, you can define whatever you read as Greek. Shannons theory is obviously of no use if the language is unknown or with your words if the "good hypotheses" are not available.

Chadwick is talking about being "aware of what Greek would look like at this period". The plausibility of using Greek at the time in question is an other topic. Kadmos 11:31, 21 October 2005 (UTC)

Yes, the correct decipherment needs to start from the correct language. In the case of the Proto-Ionic Solution, the choice of the language was not arbitrary, but came from a statistical study, which showed that it had to be a Ionic dialect. The fact that the Risch-Chadwick Theory said that such a thing was "impossible" was therefore a decisive criterion concerning the decipherment itself : "What was true ? The Risch-Chadwick Theory ? Or the existence of a Ionic dialect c. 1600 BC ?". The answer has been : the second statement is the correct one (because there are, for instance, a lot of "proto-ionisms" in the Mycenaean tablets).

In a correlative way, there is no need to question, like Chadwick does, "what Greek would look like" c. 1600 BC. The answer is now known concerning the Phaistos Disk's Greek language. And contrary to what you seem to think, it is not a kind of "invented language". Because there is no large "degree of liberty" left for the decipherer with such a dialect : it has to be the expected intermediary between "Common Greek" and "Classical Ionic", which are both well known. For instance, "child" has to be <pawis> or better <payis>, intermediary between Common Greek <paw-id-> and Ionic <paîs>. And if <payis> is found (as it has been the case), then Ionic <lâïs> coming from <lâw-> must be also written with an -y in the Phaistos Disk's text. And this is the case. (User 80.90.57.154).

To argue that "Proto Ionic" should be a mixture from "Common Greek" and "Classical Ionic" is like expecting Latin as a intermediary between "Common Spanish" and "Classical French". Such a statement is absurd only. Kadmos 20:06, 21 October 2005 (UTC)

What kind of a linguist are you, for confusing "phonetic evolution" with "mixture" !?.. I have written about "the expected intermediary" between "Common Greek", i.e. the ancestor of all the Greek dialects (= a language spoken probably c.3500 BC), and the "Classical Ionic", known from IXth Century BC inscriptions... It is your comparison which is absurd !... What one can say is that Old French, a language spoken in France during the Middle Age, is "the expected intermediary" between Latin and Modern French. And even if Old French is often closer to Spanish than Modern French is (for instance : Latin <cappa>, Old French <chapa>, French <chape> v./ Spanish <capa>), Spanish has nothing to do with the phonetic evolution which has led from Latin to Modern French, Old French being the intermediary !... (User 80.90.57.154).

You are contradicting yourself if its necessary for you to know Latin to build "Proto French". You cannot travel in time to hear "Common Greek"! For our example, that means that you do not know Latin. All you have is French, Italian and Spanish to build common "French Italian Spanish". That you add some French in the end doesn't change anything. All you receive is common "French French Italian Spanish" and not the intermediary between Latin and French. Your argumentation that your degree of liberty building Proto-Ionic is not large enough to be considered in Shannons theory is absurd. Kadmos 09:37, 22 October 2005 (UTC)

You have obviously a big trouble in understanding what an intermediary form is !.. The phonetic evolution "Common Greek" --> Proto-Ionic --> Classical Ionic is strictly similar to the phonetic evolution : Latin --> Old French --> Modern French. The only difference is that "Common Greek" has been reconstructed by linguists (as could have been Latin, if necessary, by comparing French, Spanish, and Italian) when Latin is directly known from inscriptions. But this doesn't change the validity of what I wrote concerning the "degree of liberty" concerning the reconstruction of Proto-Ionic !.. Because "Common Greek" is pretty well known, and there are tens of books on it, that you seem to completely ignore ("Dictionaire étymologique de la langue grecque" of P. Chantraine -- "Aperçu d'une histoire de la Langue grecque" of A.Meillet -- "Morphologie historique de la langue grecque" of E. Fleury -- etc. to quote a few of them). (User 80.90.57.154).

You wrote it yourself "The only difference is that "Common Greek" has been reconstructed by linguists when Latin is directly known from inscriptions." From that you cannot say "Common Greek" is known like Latin. Kadmos 16:18, 23 October 2005 (UTC)

This doesn't change the fact that "Common Greek" can be considered as sufficiently well known for hindering anybody to "invent" it as he likes. (As you asserted, when you wrote : "you can define whatever... as (Common) Greek"). (User 80.90.57.154).

First you wrote about a "Proto-Ionic" solution. Now you are talking about inventing "Common Greek". First there is no large "degree of liberty". Now it is only known enough for hindering anybody to invent it as he likes.

Even if we assume that "Common Greek" is well known a solution between a "reconstructed Common Greek (3500 BC)" and "ancient Greek (800 BC)" is far away from being unique. Therefore, pleace name some publications beside Faucounaus saying that Shannons formula is of some use here. Kadmos 21:30, 23 October 2005 (UTC)

"Archaeological Decipherment" by E.J. Barber, page 204, with a correct calculation of the "Unicity Distance", but a slightly inaccurate conclusion : it is said that the solution would be "highly suspicious". In fact, it has just to be proven, in a way or in another (Application of the solution to a second text, or verification of all its consequences), because the length of the text is too close from the "Unicity Distance". In other words : the length is big enough for finding a unique solution, but not big enough for being absolutely sure that this unique solution is the good one. Satisfied now ? (User 80.90.57.154).

First you wrote "But some scholars disagree". Now you can only name Faucounau as example. As you say yourself Barber was using this formula to come to the conclusion that any solution would be "highly suspicious".

First you say "The decipherment is possible". Now you say the "Entropy" is "not big enough for being absolutely sure".

Seems to be a joke only. Kadmos 00:46, 24 October 2005 (UTC)

You seem to be totally unable to understand the differences between a)-"the length of the text is too short for a decipherment" b)- "The length is long enough for a decipherment, but the solution has to be verified" c)- "The length is long enough for a decipherment and moreover sufficiently in excess for this decipherment not to be verified".

so that, you cannot understand the difference between a)-"In the case of the Phaistos Disk, the solution is impossible to find" (wrong) b)-"The solution can be found, but is highly suspicious, as long as it has not been verified" (correct)

or between a)-"The solution is highly suspicious" (incorrect) b)-"The solution is highly suspicious as long as it has not been verified in a way or in another" (correct). (user 80.90.57.154)

You are confusing Cryptanalysis with deciphering old scripts. Kadmos 09:21, 24 October 2005 (UTC)

That is what you think. But you have no credibility in this matter, as the hereabove discussion shows. (User 80.90.57.154).

That it is necessary to know a language perfectly to use the whole "Entropy" for deciphering a text is obviously. Or did you really believe that you can decipher an encrypted text without any further knowledge using only the "Entropy". Anyway there is no need to discuss such a topic here. It's also not a question of your opinion what my credibility is. The Wikipedi rules are very clear at this point: "Wikipedia articles are not propaganda or advocacy of any kind. You might wish to go to Usenet or start a blog if you want to convince people of the merits of your favorite views." Therefore you have to demonstrate that your theory is already accepted. Because you can only name Faucouna as supporter you can not say at Wikipedia that following Shannon the text can be deciphered. As easy is that. Kadmos 18:15, 24 October 2005 (UTC)

It is necessary to know a language perfectly to use (the Shannon's formula). No !.. I am surprised that you don't understand that the Shannon's Formula gives the minimum length for a text to be deciphered if (a big if !) the decipherer has found - by chance or by any other means- the "good hypotheses". You don't need to know the language for making an estimate of the Unicity Distance. You have just to suppose "reasonable hypotheses" concerning the "Entropy". (Otherwise, you will find "exceptional figures", like for instance the 6-signs long text J.Faucounau has given as an example. See hereabove). All searchers (Cl. Shannon, J.Faucounau, E.Barber, Y.Duhoux, etc.) agree that, in the case of the Phaistos Disk, the "reasonable Unicity Distance" is c. 225 signs, i.e. inferior to the real figure. My theory, as you call it, is therefore accepted by all mathematicians. It doesn't say that the text's length is such that anyone can decipher the disk's text. It just say that the text's length is not a problem, as many people - who are not mathematicians- believe, including yourself. The real problem is in the need of checking the solution found (User 80.90.57.154).

If I say that the language must be known I name only one of the "good hypotheses" needed to decipher the text. Without knowing japanese you are not able to decide if "kokoroe" is a valid word or an error. To decide if a solution is unique or not you have to show that every word, every grammatical rule is valid. Without knowing the language this is obviously impossible.

The correct value of the "Unity Distance" is not the point. The point is your conclusion about finding the correct decipherment. And as you say this conclusion is not accepted. You wrote that the "good hypotheses" are needed and that a solution should be checked. But if you are not able to decide if all hypotheses necessary are found and if a hypotheses is good or not this has no value. Only a superficially check also says nothing. You must be able to found any error with your checks. That you have checked the fuel of your car isn't helpful if the wheels have no air and the engine is broken. Kadmos 21:19, 24 October 2005 (UTC)

If I say that the language must be known, I name one of the "good hypotheses" needed.. Yes, of course !..

You wrote that the "good hypothese" are needed and that the solution should be checked. Yes.

A superficially check says nothing. Wrong in the case its result is negative, i.e. when the tentative decipherment is contradicted by some fact. It has, then, to be rejected.

You must be able to find any error with your checks. Yes. Better said : no fact must go against the supposed correct solution.

To sum up : the checking of the supposed correct solution is the main point, not the text's length, as I said. This is illustrated in the case of the Proto-Ionic Solution by the following figures, given by J.Faucounau : time taken by the decipherment :: c. 6 years. Time taken to verify it : c. 20/21 years. (80.90.39.25 22:38, 24 October 2005 (UTC))

Fine that you have changed your position concerning the language.

Better said : no fact must go against the supposed correct solution. This is not better, this is worse! By a superficially check you will not found any contradicting fact.

It's absurd to talk about the time someone has needed todo something. The question is he able to convince anybody else. Kadmos 08:09, 25 October 2005 (UTC)

a)- I didn't change my position concerning the language. I have always talked about the necessity to start from "the good hypotheses" to reach the correct solution, whatever the value of the Unicity Distance !.. Language is one of them. It can be known (as in the case of Proto-Ionic), or not (as in the case of Etruscan). b)- It depends of what you call "superficially check". So, I can tell that the deciphering attempts supposing the Phaistos Disk to be read from the center outwards are surely wrong. No need for a more complete examination !.. c)- No !.. The time passed in the search for proofs is significative of the difficulty of this indispensable step in the case of the Phaistos Disk. Convincing people is another problem, and History of Science has shown that it took sometimes 30 years or more for a correct theory to be adopted... So, I maintain my redaction. (80.90.39.25 12:21, 25 October 2005 (UTC))

The correction made by Kadmos on Dec 1st, 2005, that it would be necessary to verify that (the proposed solution) is the only possible solution shows that, once more, Kadmos has not understood Shannon's work ! Let's just take an example : I quoted hereabove a 6 signs text, which can be exceptionnally deciphered (because of its entropy), when the "Correct Hypotheses" are chosen: a)- it's a text b)- it is written in French c)-etc. (See hereabove). It is obvious that it is impossible to show that this is the only possible solution" : because one may interpret, for instance, the same 6 signs (= 5-14/11-6-14-11) as the coded date 10/2302 (with the erroneous hypotheses : a)- it's a date b)- 5 = 1 , 14 = 0, etc). So, what is to demonstrate is that the "French Text Solution" is the good one, not that it is the unique possible one. (80.90.39.25, December 2, 2005).

Unicity distance according to The Handbook of Applied Cryptography "is the MINMUM amount of ciphertext(number of characters) required to allow a computationally unlimited adversary to recover the UNIQUE encryption key." In your example the length of the 6 signs is SHORTER then the unicity distance for a french text! Kadmos 19:56, 2 December 2005 (UTC)

You are really in a big trouble understanding Shannon's work ! The sentence you quoted supposes, of course, the implicit complement : in function of the Entropy of the text . So one has to understand the sentence :...to allow a computationally unlimited adversary to recover the UNIQUE encryption key, TAKING INTO ACCOUNT the Entropy of the text.. In my example, the Unicity Distance is, BECAUSE the exceptional figure of the Entropy in THIS case, only 6 signs long!. 80.90.39.25, December 2, 2005).

Nonsense! The definition of the Unicity distance is quit clear. See http://friedo.szm.sk/krypto/AC/ch11/11-02.html - The Unicity distance is a function of the language (or cipher)! And you know that. This are your own words: "If the length of a text is shorter than the 'Unicity distance', the text cannot be deciphered, because there is more than one solution." With Shannons formula for the Unicity distance all you get is, that there should be just ONE solution that makes sense. With other words the correct solution must be unique. As simple is that. Kadmos 23:14, 2 December 2005 (UTC)

It's really tiring to discuss with Kadmos who is unable to understand Shannon's work !.. The more as Gbrunner is taking his interventions to censor the Point of View he doesn't like ... ironically in the name of NPOV !!! The nonsense is yours. I quote the text you cited (emphasis is mine) : Shannon defined the Unicity Distance ...as an approximation of the amount of ciphertext such that the sum of real information (entropy) in the corresponding plaintext plus the entropy of the encryption key equals the number of ciphertext bits used. In other words, Shannon's Entropy depends a)- first and mainly of the Code b)- secondly of the language c)- thirdly of the plaintext itself. The more the ciphertext will be close to a randomly series, the greater will be the Unicity Distance. This is why a code which randomizes the ciphertext better than another will be more secure, and why a "Simple Substitution Code" (case of the Phaistos Disk and of my example) is the worse in regard to secrecy, Shannon's main concern, because it keeps the peculiarities of the language and of the text. In the example I've given, it's clear that the 6 signs are not taken at random : two are occurring twice, what allows the decipherment. (80.90.39.25, Dec. 2, 2005)

Read what is written about the Unicity distance instead of talking about entropy generally:

"Shannon defined the Unicity Distance ... as an APPROXIMATION of the amount of ciphertext such that the sum of real information (entropy) in the corresponding plaintext plus the entropy of the encryption key EQUALS the number of ciphertext bits used"

"He then went on to show that ciphertexts longer than this distance are reasonably certain to have ONLY ONE meaningful decryption."

"Unicity distance estimates the MINIMUM AMOUNT OF CIPHERTEXT for which it is likely that there is ONLY A SINGLE intelligible plaintext decryption when a brute-force attack is attempted."

BTW: Also in random samples it happens that sometimes a sign occurs twice.

Kadmos 17:36, 4 December 2005 (UTC)

And here you go again, with your poor understanding of the Shannon's work !.. When will you understand that Shannon has dealt with the Possibility of Deciphering a text, approaching the problem from the point of view of the cryptographer in search of security ? So, when he talks about A SINGLE DECRYPTION, he implicitely supposes that, for instance, the language of the plaintext is known by the attacker (what is always the case during a war ! The use of the Navajo language by the USA during the war against Germany was so exceptional that it could be used by radio, without any coding !).

The lines you quote are indeed correct. But I have to say, at the end of your citation : So what ?. Because, what they say is only a mathematical, precise way to say what can be said, using ordinary language, as : a)- If the length of ciphertext is less than the Unicity Distance, there is no possibility to decipher the text, whatever the brute-force attack, because there is not a single solution, even if the decipherer uses the good starting hypotheses. b)-if the length is greater than the Unicity Distance, then ONLY A SINGLE decryption DOES EXIST, (and therefore, there is a possibility to decipher the text IF the decipherer has found -by chance or by anyother way- the good starting hypotheses, the problem being that IF the length of the ciphertext is not a lot greater than the Unicity Distance, a verification is needed). So, when the length of the ciphertext is greater than the Unicity Distance, there is no need to verify that ONLY A SINGLE DECRYPTION does exist (it existence is warranted by the Shannon's Formula), but what is (eventually) needed is to verify -by a way or another- the value of the decryption found.

Clear enough for you, now ? (80.90.39.25, December 4, 2005)

Fine that you have changed your position concerning the Unicity distance.

Also fine that you admit in the end that Shannon was supposing that "the language of the plaintext is known".

But there was nothing written like "if the length of the ciphertext is not a lot greater than the Unicity Distance, a verification is needed". This is only your interpration!

Pleace reread your changes: "... in theory, the text's length IS SUFFICIENT for reaching the correct solution ... the text's length being NOT SUFFICIENT for being sure of that."

Kadmos 22:44, 4 December 2005 (UTC)

I didn't change my position ! You have reached a better understanding of Shannon's work. As for the need of a verification when the length is not a lot greater than the Unicity Distance, all the scientists who have tried to apply the Shannon's Formula to the deciphering of old scripts, agree on that. It's JUST PLAIN COMMON SENSE !!!

My changes are perfectly OK and make sense, even if you don't understand them! Please try again rereading them slowly! (80.90.39.25, Dec.5,2005)

Please, do not make personal attacks. Personal attacks damage the community and deter users. Nobody likes abuse. Discuss the facts and how to express them, not the attributes of the other party. BTW: You will confuse the reader and muddle your point, if you write that the text's length is not sufficient shortly after writing that the length is sufficient. I have tried to make that point clear. Thoralf 10:33, 5 December 2005 (UTC)

Sorry if my answers to Kadmos seem to you as personal attacks! I will try to lower their tone, but one must understand my irritation in front of Kadmos' attitude, using words like "Nonsense!" or "Absurd!" when it's he who is wrong. He was wrong, for instance, saying that Shannon's Formula is of no use in the case of the Phaistos Disk's decipherment, when it has been used by several scholars ; he was wrong saying that the Unicity Distance is not the point , or misunderstanding the question of Unicity of the Solution.

BTW, you seem to have the same problem concerning this question, so let me be more explicit about it : Shannon was dealing with cryptography. So, he was implicitely supposing that the encryption was corresponding to an encrypted text, coming from a plaintext in a known language, and he could talk about a unique solution. If you abandon this implicit condition, the notion of a unique solution vanishes, or better said, has to be modified. For instance, during a war, a coded message is decrypted as Order to attack tomorrow. Well, a fool can also say : "It is not a message. It's the numbers the ennemy intends to play at the roulette in Las Vegas". And there is no more a unique solution because the fool's solution is theorically possible... So, when one deals with something which may not be a text, and of which the chosen language may not be the good one, like this is the case with the Phaistos Disk, the notion of unique solution has to be understood : unique solution if the used hypotheses are the good ones, and one has to verify the solution discovered , for instance, like in the (pretty stupid) example I gave hereabove it can be done : By verifying the consequences of the decipherment (verifying that the ennemy prepares an attack, or even waiting until tomorrow, to be sure that the decipherment was good). To go back to your remark, one has to understand : From the Shannon's Formula, the length is sufficient if one has to deal here with some kind of syllabic text, with a Simple Substitution Code concerning the phonetic values, and with a not-exceptional Entropy (= Reasonable assumptions). As a consequence, if the other starting hypotheses (in particular concerning the language) are '"the good ones", the solution can be found (= Unicity of the Solution). But the text's length is not sufficient to warranty that the chosen hypotheses were surely the good ones. Therefore, a verification is needed by examining the consequences of the solution found. I hope to have clarify the things, this time... (80.90.39.25 Dec. 5, 2005)

@I didn't change my position ! : First you wrote "In my example, the Unicity Distance is ... only 6 signs long.", now you write "If the length of ciphertext is less than the Unicity Distance, there is ... not a single solution ..."

@As for the need of a verification : You say it yourself, it is common sense for "the deciphering of old scripts". It has nothing to do with C. Shannon and the Unicity distance as you wrote first.

@My changes are perfectly OK and make sense : This was only a hint that it's not easy to understand. Thoralf also was writing that it was a little bit confusing.

@that Shannon's Formula is of no use : The sentence was "Therefore his theory is of no use here". Yourself wrote "Shannon has dealt with the Possibility of Deciphering a text, approaching the problem from the point of view of the cryptographer in search of security ?" also you have admited that Shannon was supposing that "the language of the plaintext is known" whereas this is not the case for the Phaistos Disc. Nothing else I was writing in the response you criticize : " Shannon was talking about cryptography. For a encrypted text he was able to assume that the language is known. Therefore his theory is of no use here."

@the Unicity Distance is not the point : Where is the problem if I make clear what in my opinion the point of discussion is?

@misunderstanding the question : see @I didn't change my position !.

@the example I gave hereabove : Even for a date there is more then one valid solution : 10/2302, 10/2502 ..., 12/3023 etc. Therefore without further informations it is not possible to say that 10/2402 is the good solution. This is because the length of the 6 signs is shorter then the Unicity distance. For the Phaistos disc, because of our weak knowledge about the time in question, it is already a problem to validate a solution. How will you decide for the Phaistos disc if a solution is valid or not, if not by showing step by step that there is always only one valid explantion? For instance the reading direction is disputed until today. If you can determine the reading direction this will be a big step. The same is true for determining the language etc. In the same way the number of valid solutions for your example depends on the question if the first number tells us the month or the week. In the second case also 13/2012, 34/2032, 43/2042 etc. are valid solutions even if you are able to verify that the 6 signs are a date.

Kadmos 18:24, 5 December 2005 (UTC)

It's really discouraging to discuss with you ! a)- I didn't change my position. Your criticism is nonsense. As this text can be deciphered (because of its abnormal entropy), it means that the Unicity Distance is 6 in this particular case (a thing that you don't seem to understand !!!) b)- the need for verification : of course, it has to do with the Shannon's Unicity Distance ! (What you don't seem to understand !!!) c)- Use of the Shannon's Formula . Why would it be of no use as you pretend ??? What hinders anyone to suppose (rightly or wrongly, it doesn't matter!) the language of the Phaistos Disk to be a known language, and apply then the Shannon's Formula??? d)-the example I gave hereabove : Of course, there are several solutions ! And for the reason you give, concerning the Unicity Distance in the case one supposes it's a date ! Because the Unicity Distance = 6 ONLY IF the "good hypotheses" that I mentioned (It's a text, written in French, etc.) are taken in consideration. Supposing that it's a date doesn't respect this condition ! (a thing you seem unable to understand!!!) e)-How will you decide whether a solution is valid or not : please read my preceding paragraph (with an example!) in this ridiculous discussion : by its consequences ! As simple as that !.. (80.90.39.25, 20.15, Dec. 5, 2005)

a) For this purpose you need a better example, for instance 5-14/11-14-14-11 (with only 10/2002 as valid date, if you know that 10/3003 is to far away). For 5-14/11-6-14-11 you cannot deny that beside 10/2402 also 10/2302 and 10/2502 are valid. Only if you know that 6 stands for 4 there will be a unique solution here.

b) Please explain. If you only repeat statements without any explanation nobody will be able to understand you.

c) At first, that there is no language, we know good enough to be sure about an valid solution, for the requested time for the requested area. Secondly, because it matters if you only guessing about the language. You can not add the entropy of your guesses!!! To be sure you have to verify that for the other languages no valid solution does exist. (Otherwise it will be possible to decipher a text with only a single sign without further knowledge. All you have to do, is to guess that the solution is "tomorrow". Under this guess the Unicity distance is a single sign.)

d) see a)

e) What do you mean? Is there an date given on the Phaistos disc on which some aliens will attack the earth ;-)

Kadmos 22:08, 5 December 2005 (UTC)

a)-When will you understand that the Unicity Distance is not the same in the case the encryption corresponds to a plaintext in French, or to a date? b)- Easy to understand : IF (with some hypotheses) the Unicity Distance is a lot greater than the length of the text, all the other solutions (based upon different hypotheses) have no chance to be correct : the evidence in favour of THIS solution is too overhelming. There is, then, no need of a verification. But IF the Unicity Distance is in the range of the text's length, there is a doubt, so a verification of the solution is necessary. c)- Your statements have no basis : 1)- you don't know whether the language is "sufficiently known" to allow a decipherment or not. Why the language would not be Luvian or Proto-Ionic ? 2)- Guessing about the language is a perfectly correct move, which may succeed or fail. The verification will tell. And once the language chosen, the corresponding Entropy may be evaluated. 3)- ???? (I cannot understand your final objection) d)- see a) e)- I mean that there is ONE SOLUTION which can be (and has been) VERIFIED by its NUMEROUS CONSEQUENCES (more than 30 verified!) : the "Proto-Ionic Solution". If I don't ask that to be mentioned, it's because the fact, that THIS solution is the ONLY GOOD ONE, has not been universally accepted for the time being. Thanks to people like you, who have a big trouble understanding the consequences of the Shannon's work concerning the possibility and the credibility of a decipherment !!! (80.90.39.25, 23.40 Dec.5, 2005).

a) Where did you read that they are the same? b) Nonsense. It is always necessary to validate a solution. That you name it verification instead of validation doesn't change something. Real verification is needed for old scripts because of the poor knowledge we have about this time. It is necessary to demonstrate that the solution isn't made to fit to the known inscriptions only. c) 1) I know! Luwian was used after 14th century BC and for Proto-Ionic no respectable sources are available. 2) Unfortunately it will only fail in theory. The number of suggestions for decipherments illustrates that for most people it is easier to ignore the errors then to admit that they have failed. 3) Even if you didn't like it the difference between guessing and knowing still exists. e) see b) Kadmos 23:11, 6 December 2005 (UTC)

It seems that your discussion have diverged from what was proposed initially. It's not longer about the redaction of the article. If you want to go further please be polite and use usenet or email. Thoralf 08:02, 7 December 2005 (UTC)