REMOVED: Was looking at a non-authentic scan

, but it is generally through an experience-driven feeling of "knowing" that it is right, without showing the exact mathematical arguments about why it is so.

I do not at all doubt the correctness of the solution, simply because it confirms by producing a text that matches the historic context. If you had massaged a possible, but unintended, solution into the cipher, then I can not imagine this very unlikely event then would on top match the social and historic (sad) context.

Speaking of mathematical evidence, I suggest to look at the arguments in unicity distance. There is a unicity distance due to the cipher being homophonic. There is the real length of the 340, providing us with a certain amount of information, that exceeds the minimum by some delta.

If you use less bits worth of information for re-arrangements than this delta, then you can argue a mathematical evidence – even without referring to the itself overwhelming argument of historic and social context – that the solution is the one and only one correct. We need to count how much bits worth of information was used for the corrections, and consumed off from the delta. Shannon’s information entropy I expect would give the formal evidence then.

Another mathematical question to me still remains: Why do the zkdecrypto/AZDecrypt scoring algorithms work so well? I do not doubt at all their results, but somehow keep looking at them as ad-hoc engineering and of over time optimized origin, without that I can recognize the statistical reasons for their strong performance. They are not what I would anticipate machine learning expert to start with coming from a theoretical background.

I ran the solution through the statistical approach that I tried in cDecryptor, and very little surprising it confirms that the solution is natural text and finds no better. I find it a not completely trivial result, because it is an AZD-independent, likelihood-based scoring algorithm. Left to be done is if a statistical scoring algorithm would be able to squeeze better hints out of the first 153 characters of the period 19 transposition than the zkdecrypto/AZdecrypt algorithms did.

I fully understand that it was a strong personal effort in combination with a certain amount of luck, that the sporadic correct words that AZD squeezed despite the noisy signal, caught David’s attention (who must have spent a significant of (Corona-?) time staring at zillions of garbled output and brain-filtering a myriad of possibilities). Impossible without the strong results of the zkd/AZD algo’s. But the scoring might be "only" the best we know, but not necessarily that might be possible. Having said so: I do not know any better. It is only that the question puzzles me. Not sure it is worth to still spend the time, now that the 340 is doubtlessly solved. With these algorithms.

Unlike the Zodiac case, there was plentiful evidence in the Manson Family case. Unsurprisingly, detectives in both cases suspected a possible link between the Manson Family and Zodiac. Many of the cult participants became informants and provided hours of verbal evidence. But a connection between the cases never materialized.

True, but this cipher — which might contain the Manson phrase about "Life is Death," wouldn’t be translated for 51 years. Wonder if that would have been considered a connection at the time, if they’d been able to read it?

Possibly at the time, but the "death is life" slogan seems too generic to suggest a connection at face value. It would be another story if the cipher included unmistakably Manson phrases (like "helter skelter" or "ATWA").

Manson’s crimes were motivated by paranoid racist beliefs while Zodiac’s writings are light on politics without a hint of racism.

BDHOLLAND, you raise a lot of interesting points about how to confirm this solution. I hope to address some of them in my next video, by showing more detail about how the message might have been constructed. I think it is good to be skeptical and to validate claims. So far, every cryptographer I’ve talked to who has taken the time to analyze the key has concluded that they believe it to be true, but it is generally through an experience-driven feeling of "knowing" that it is right, without showing the exact mathematical arguments about why it is so.

One way I think about it is: How much information goes into producing the proposed key? For example, Corey Starliper is an extreme example, because he put an entire invented solution in his key. In his case, he added too much information into his key, and not enough of it was coming out of the cipher. In the 408, the only information that goes into the key is the list of substitutions. Everything else falls out. But you could also say some other small bits of info are "added", such as correcting some of the encipherment mistakes he made. But in that case, the amount of information added to the key was minimal.

In the 340’s solution, we had to add a bit more information: Not only do we have the substitutions, but we have a transposition scheme that is applied consistently to 2 sections. By themselves, those are enough to get really good solves from those sections. But the 2nd section produces somewhat garbled text until the transposition errors (intentionally made or otherwise) are corrected. So in that case, we have added a little more information to the key. However, I believe it is justified because when you use English n-gram statistics to measure the somewhat garbled text, it still measures very closely to normal English text. Much more closely than random text does. So it is evidence of a real message even without the corrections.

There is some subjectivity applied to the 3rd section, since we are guessing where the word divisions are, and which sections to reverse to produce the message. But in the end, those few additional steps (which again add information to the key) produce a very good and coherent message.

Ultimately, we got much more information out of the key than we added to it. So in that sense, that’s why we feel it is correct, compared to other solutions.

Coming at this from another direction, we could see if this same method could produce equally plausible but different solutions. Based on how systematic the overall decipherment method is, I think it would be extremely difficult to apply the same method in a slightly different way but still produce as coherent of a message as this. I think this would be difficult to quantify – we need to recruit some mathematicians.

I would agree with you that what you have described here is consistent with how an amateur Zodiac would go about a puzzle and muck it up in the process and require degrees of subjectivity and tweaking to get it work.

This is something many people in the community have been pointing out is a valid approach to solving Zodiac related problems over the many years. Like Bauer’s Z340 solution as an example.

The problem I am having though is that this type of methodology is one that you have been very unhappy with others using, including myself or Bauer and many others. I am just pointing out why your solution is partly involving methodologies you have been vocal about rejecting in the past.

For example, appeals to arguments from authority (experts have a fuzzy feeling in their tummy about it) or appeals to ad populum (nearly all the experts I know…)

In the past these logical fallacies for you have been a reason to be vocally dismissive of people’s work on here for containing such points of contention.

Falsification justification. This means null hypothesis testing. This was a cornerstone of your reason to reject many solutions to various puzzles out there. Without falsification you would say we had no way to segregate them all out. The very ability to prove something is wrong.

Objectivity. Meaning no subjective mechanisms involved in reaching solutions. That is why you elevated mathematics to the level of a science. It had objective power. Yet in your solution you allow for subjectivity because a little tweaking and not a lot is all you need to do to get it to work.

Statistical significance. This is part of null hypothesis testing. This was part of a benchmark for being able to show with a maths proof that the solution was probably right. It had probabilities going for it. Your solution has probabilities going for some of it but as a complete solution it doesn’t have the full scale objective math proof you required from others.

Proving causation. Attributing a mistake to the Zodiac to get a solve meant proving the Zodiac is the cause of the mistake.

Going outside of the puzzle. Proving the Zodiac used the method he did by appeals to things outside of the puzzle itself.

Here are more examples of what I am talking about. Our interactions with you when it came to make presentations and the types of rebuttals you were giving.

https://www.reddit.com/r/ZodiacKiller/c … _findings/

https://www.reddit.com/r/ZodiacKiller/c … &context=3

We have been criticized by you for not meeting your standards, yet it appears that these are no longer a problem for you because you have the type of solve you do.

You realize you can only work with what you have and that if the Zodiac wasn’t able to provide you with a puzzle and solution of the quality of mathematical proof you required from everyone else including falsification ability then that was just the way it going to be and in your case, seems to be.

I hope you see that what I am doing here is not saying you are wrong, quite the contrary, that you have come around to accepting various points we were all making about the need to allow for subjectivity, appeals outside of the puzzle and not the hard math proof you seem to have the bar raised at. Your pole vault came in short of your own standards but because the vault was so high you still let it count. Would you have been so forgiving if others did this? IMO, with all my interactions with you, no, you wouldn’t have been. Sorry but just my experience reading your criticisms of others work. I am glad however you do have the solve you do. Now you can see with your own eyes and experience what many of us have been trying to tell you for quite some time. Expecting a solid math proof like the Z408 was highly unlikely and the solutions would require subjectivity and some come in well under your own standards that you set for others.

Anyway enjoy what you did. You worked hard on it and deserve it for the huge amount of effort you and others put in. A lot of work there to just dismiss out of hand over trivial criticisms when it came to the big picture. The big picture is what we have been trying to get you to see. The big picture is what you have presented for your solve in the end.

First, that this is revealed as a real code, a complex one, one that defied the efforts of the FBI and others to decode it for 50 years. I think it tells us that Z was very intelligent, had some real skill in codes and mathematics.

I think the fact that it took this long, and required a level of computational sophistication that wasn’t even perceived of in 1969, tells us the exact opposite. Anyone with their hands on a basic cipher handbook could have layered on a few of these strategies. But what they wouldn’t realize that in doing so, it would make it close to impossible to untangle it. Why bother? I can’t imagine that he thought he was creating a code that would be so difficult to crack. If he was really skilled, he would have realized that.

I think the Z13 and other short ciphers are also hints that he really wasn’t all that much of an expert in codes and mathematics. Perhaps there’s something there that eludes the experts, but I think that Occam’s Razor would suggest the he just didn’t understand that such short ciphers generally can’t be cracked with a unique, and sensible, solutions.

edit

For years many assumed the cipher was improperly coded or deliberately unsolvable. The fact it took 51 years to solve what is an ingeniously encrypted code suggests Zodiac was in fact quite intelligent and skilled in cryptography, possibly with a military or mathematical background.

Another interpretation is that any sort of multi-layered ciphering process – it doesn’t have to be sophisticated in any way – is going to be extremely difficult to crack.[/quote
So, based upon the 408 and 340, how would you assess Zodiac’s codemaking skills? Was he a novice? Did he receive some intermediate level training perhaps in the military? Or was he a next level cryptologist with exceptional skills and training?

My feeling on Z’s level of sophistication has been that he worked around codes, knew some tricks, but probably didn’t work day in and day out on them. Hence he can come up with elaborate, sophisticated patterns far beyond what the lay person would get from a cereal box. But it would also account for him not disguising the double letters on the 408.

Disclaimer: my theory has been that Z was an engineer or computer guy working in intelligence and anti-submarine warfare. Which would put him around codebreakers, and needing to know things about codes, but not a codebreaker himself.

It’s like as a technical writer, I know more than the lay person about the subjects I’m writing about, but I’m not an expert.

I think the fact that it took this long, and required a level of computational sophistication that wasn’t even perceived of in 1969, tells us the exact opposite. Anyone with their hands on a basic cipher handbook could have layered on a few of these strategies. But what they wouldn’t realize that in doing so, it would make it close to impossible to untangle it. Why bother? I can’t imagine that he thought he was creating a code that would be so difficult to crack. If he was really skilled, he would have realized that.

I agree with a little knowledge from a code book and being relatively amateurish you can easily make a cipher too hard to solve without modern computer brute force.

The drab decoded 340 message does not measure up to the difficulty of decoding the cipher. The easily decoded 408 message is excitingly terrifying. Starting off with "I like killing people because it so much fun. Much more fun than killing game in the forest"

Another thought is the last two lines which are probably the most controversial decoding could reveal a vague threat or insult to Melvin Belli much like when Zodiac sent Paul Avery the Halloween card saying "You are Doomed". A reason to make the Cipher difficult to decode.

Several words are spelled backwards but turned around in the initial decoding released by Oranchak. Including Life, In, Be, Paradice. Belli name is also spelled backwards and should be given the same weight at Paradice because the basic message was inspired by Melvin Belli talking to the caller about the "Gas Chamber" on the Dunbar TV show. Belli was a flamboyant Lawyer who was wealthy with a good life, likable personality, opposite of the Zodiac. Might be the cause of jealousy in this life time within the mind of Zodiac.

Zodiac wrote a Letter to Belli a month and a half later on Dec. 20, 1969 asking for help sarcastically? Talked about being out of control and afraid of killing more. Reaching out for help it seems. This contradicts with Zodiac confidence in the 340 message. On April 28th, 1970 Zodiac sent a jolly roger greeting card to the Newspaper ridiculing Belli in the Buttons Card. FYI….Belli would regularly fly a Jolly Roger flag above his mansion.

Could the last two lines be a insult or veiled threat to Belli as decoded below….

BELLI AN EASY LIFE, NOT IN DEATH PARADICE.

BELLI AN EASY LIFE, NO PARADICE IN DEATH

Because Belli has no Slaves for Paradice which makes your life terrible in the afterlife according to Zodiac.

Hi.
Well, first of all, I don’t take what I’m going to post as true, not least because ALA has been discarded.

However this old observation of mine here http://www.zodiackillersite.com/viewtopic.php?f=39&t=2939and on my blog came to mind.
Basically :
In the first line of the classic cipher we have been following for years, which we can now call "transposed cipher" we have alphabetical symbols
HERVPILTG
When we sort alphabetically
we have
EGHILPRTV
Using what we call Fibonacci design in the first 5 letters, we would theoretically LEIGH

Dessert
LEIGH PRTV

I found it interesting, but not conclusive, of course, that in the cipher the author mentions a TV show.
PR, at least from what I’ve researched until today, is meaningless.

don’t take it seriously enough to be nervous with me, as this has been discussed before.

Marcelo

In the first line of the classic cipher we have been following for years, which we can now call "transposed cipher" we have alphabetical symbols
HERVPILTG
When we sort alphabetically
we have
EGHILPRTV
Using what we call Fibonacci design in the first 5 letters, we would theoretically LEIGH

The observation you make regarding the sequence of letters that spell LEIGH (12, 5,9,7,8) is a function of his name, not of any Z related code.

As far as the letters to spell LEIGH being present in the first line of the cipher, I think it is even more curious that one can make "KACZYNSKI" from the letters in the final 2 lines. In fact, if we use the backwards "D" and "E" twice, we can make THEODORE from the letters in the first line, too. Not to mention his middle initial, J, very near the center of the cipher.

I’m not saying this is necessarily significant, but I think it is much more curious than finding just LEIGH in the first line.

Hi Mr Marshall
Well, I just brought it all down becaase for the TV show mentioned in the cipher, as I said, nevermind.
Marcelo

One thing: I hadalways assumed the whole slaves in Paradice thing was bunk, he didn’t believe it, it was a red herring.

Now, I don’t know. He seems to have really thought about it a lot.

I’m not sure he’s not trolling on some level but what his choice of victims says about who he wants as “slaves” is an idea to explore. It doesn’t seem to be directly sexual. It’s guys and girls on dates and a cab driver. This probably doesn’t rule a lot of people out but Z seems to want power to have respect in the normal areas of life. I’d say it again suggests that Z was a loner, without much dating or true friendship. He wants to force people to respect him and like him in normal life. Since he can’t get that in this world, he’ll get it in the next. They’ll be forced to include him.

Has someone tried to decode the 13 character cipher using the symbol mapping from the 340 cipher?

So I get this (? are the unknowns): DREA?A?O??EDO

I thought as he asked in his identity cipher letter if his previous cipher has been solved already (which of course he knows, if that were to be the case, but he likes to be very annoying) it could be so that the decryption depends on the solution of the 340 cipher.

The fact that it starts with DREA (or DREU, depending on how you correct the first part of the 340 cipher) I found interesting.

I have another question: in the first part of the cipher, we move diagonally and each of those moves is also a Knight move in chess.
Now, after solving the first part, you see the last lines are also solved, so you could assume it is correct AND all symbols are mapped then.
You also see the "LIFE IS" and "DEATH" parts deciphered.

So in that sense, the second part could also be made more difficult by the Zodiac, as all unknowns are known and therefore you only need to form words and
that is where the second part could have been made more difficult.
So without altering part 2 and having mapped all symbols after solving part 1, you move in Knight jumps forming
words. The interesting thing is that you can in fact form the word "sooner" by making Knight moves.
The reason I was thinking about this is because I somehow still find the second part weird, so many mistakes and I can imagine you need to jump around the text in Knight moves.
Maybe someone likes to try this out.