I've spent a fair amount of time on K4, and my conclusion is that it's simply a poor puzzle. At this point 24 of 97 characters have been revealed, and yet there's seemingly still not enough information pointing to how the known plaintext corresponds to the ciphertext. Over the decades everything reasonable has been tried and eliminated, which means the solution is likely to be unreasonable.
I'm inclining to this too. I heard about it first on Usenet in the 90s, and started looking at it again seriously in June 2017 when I came across the Bauer paper.
But after the 2020 clues (another 13 letters), it became clear that it wasn't any single ACA cipher type, and it was probably something very difficult (because of K4's very low index of coincidence, i.e. 0.036 just below "random" 26-letter text at 1/26, plus the huge number of revealed plaintext letters "in place" i.e. letter-for-lettter correspondence).
That plausibly left a combination of two or more well-known cipher types, but if they were somewhat complex ciphers, the chance of solution would be rather remote.
Hence I always thought a "good" end to the puzzle would be like the book "Masquerade" by Kit Williams where the only guy in cahoots with the creator (Bamber Gascoigne) thought the initial puzzle was an unrealistic challenge, but Williams released clues which enabled two schoolteachers to solve it. So that part was satisfactory, even if hardly anybody remembers the solvers' names!
In contrast, the cribs for K4 haven't helped at all.
What makes a puzzle like this “unreasonable?” Like would it be a sort of “you had to know that you needed a bit of graffiti on a truck stop stall outside Anchorage” unfair scope issue or is there a different kind of unreasonable I cannot currently imagine?
Also, another example of an "unreasonable" challenge - the "Decipher Puzzle" https://cisa.umbc.edu/wp-content/uploads/sites/468/2017/09/S... -- from 1983 to 1985.
You would think that one of the lessons of that is that someone could jump in right at the end and solve it after several clues were released. That hasn't worked with K4, which is increasing people's skepticism.
It's easy to make a puzzle that's hard. "Guess the number in my head" is hard. It's not fun for the solver or reasonable. "Unscramble this text which was XORed with the Windows 3.1 solitaire EXE" is likewise.
Good puzzles, even hard ones, should have some idea which way to approach them and should offer a method of attack other than brute force.
Here's an essay I wrote 15 years ago about another "unreasonable" puzzle:
Here's what's up for sale from RR Auction
https://www.rrauction.com/jim-sanborn-kryptos-k4-solution-au...
The Wired piece has Sanborn saying the reserve should be "around $300,000."
It sounds like Sanborn really doesn't think it'll be solved before the auction date of 20 November (his 80th is on 14 November). If it does get solved due to this publicity bump, that's huge earnings foregone.
Perhaps he knows it is still an "unreasonable" challenge even with the 24 known letters.
A one time pad would be unreasonable.
Edit: Unless the one time pad is a well known relative document, such as the Declaration of Independence.
There are SO many things he might have done, with no pre-determined rules. Like, algo-scramble.
Starting with the n-char plaintext, make it a loop. Now move the second letter two places to its right, the third three places, and so on ... until arriving at the original nth letter (painted red?) Or, starting with the digits of pi, move the second letter 3 to the right, the third 1, the fourth 4, und so weiter.
Doing a frequency on 97 weird letters wouldn't help much.
Would that be akin to me offering a hash string as a puzzle and asking for the 10GB video file as the solution?
Sort of. A one time pad does not destroy data, but a hash will.
Wikipedia has a good example: https://en.wikipedia.org/wiki/One-time_pad
In their example, "HELLO" is the plain text, "XMCKL" is the key, and the ciphertext is "EQNVZ". However, with a one time pad, an equally plausible plain text is "later" with the key "TQURI". Thus, without anymore data, it is simply impossible to know what the original message is.
Probably correct. Different from the other cyphers, the number of symbols is short, and correlating part of the plaintext that has been revealed gives poor measures for the full string length. It has been said that the other solutions are required to solve K4, so if the solution relies on something like character alignment, matrix coding or an even more convoluted permutation arrangement, this can look (or directly be) a one-time pad cypher which are arguably the most difficult to solve.
Does it’s S shape, or the shadow it casts or any other physical representation of it have to do with the message?
Well, outside of Sanborn and his collaborators, who knows. When the puzzles were first revealed and people started trying to crack them, some of them explored out of the box approaches like the design of the sculpture, odd-shaped letters, shadows of the symbols, it's geographic position, etc. However eventually all first 3 turned out to be classic cryptographic algorithms (Vigenere for K1 and K2, transposition for K3), with the information to solve them contained within the cyphertext of the sculpture. For K4, Sanborn has hinted that this may not be the case.
is it hinting at S-Box?
> These cryptographic systems were not designed by the sculptor himself but by Edward Scheidt, who retired as chairman of the CIA’s Cryptographic Center in 1989.
The article left me with a nagging question: Doesn’t the designer of the codes deserve a share of the proceeds of the auction? He’s still alive according to Wikipedia. It sounds like the unsolved code is what makes the art especially valuable. Was the cryptographer’s effort a “work for hire”, so he doesn’t get anything from the sale?
Good point, and it's also entirely possible the code designer just did a terrible job. e.g. around 57:00 of https://youtu.be/JOXPYkjvDaA
As Kryptos gots a huge amount of media attention in 1999, references to him changed from "chairman of A cryptographic center" to "chairman of [THE] CIA's cryptographic center" when it doesn't even seem that it has such a center.
And the featured story (around 52:00 of the video) has him apparently claiming credit for helping solve a Caesar cipher!
https://web.archive.org/web/19990501000000*/http://www.tecse...
a direct reference to the Berlin Clock. Sanborn further stated that in order to solve section 4, "You'd better delve into that particular clock".[2] However, Sanborn also said that, "There are several really interesting clocks in Berlin."
I have discovered a truly marvelous solution to this code, which this text box is too small to contain.
Up vote for reference to Fermat!
It seems the solution will continue to iqlude us.
what text box
I know. The difference is, his scribbling was FOUND in the margin — but the comment had no text box when it was read :)
“lies” is grammatically incorrect here. Shouldn’t it read “lays”?
Think "therein lies the rub"
And the secret key is: puppy
Nah, it's always "swordfish".
Gotta be 42.
Nah, it’s password123
12345, same as my luggage
Take your upvote. ;-)
hunter2
I feel old now
All I see is ****
3 asterisks short of a reference :)
That’s how you know it works.