Fable 5.1 Solves the Cyphral Distich, a 370-year-old cipher
223 points by u1hcw9nx 2 hours ago | 72 comments

redfloatplane 2 hours ago
A very neat problem and result. I often find myself swinging between "It's so over" and "We're so back" - some days I roll out of bed thinking I could have Claude solve some random unproven OEIS sequence before breakfast; other days, I wake up in a cold sweat worried about the fate of humanity and what the world might look like in a decade. I think it's that I don't have a very high p(doom) or p(utopia), and I don't really have any solid conviction on how this whole thing is going to go, so my vibe-o-meter jitters between 'fine' and 'not fine' constantly. It's just such an unpredictable moment. Anyways: really neat to see this use case. I myself recently used Claude to finally do an relatively exhaustive study of the location of heretofore-unlisted formal gardens in Ireland in the early 1800s and early 1900s, by having Claude write the tooling for me to manually annotate a few dozen on tiles of historic maps, and then running some CV model across the rest of the tiles using my input. I'd been planning to do this project for over a decade, but I could never find the time (or the enthusiasm) to learn all the details of how to do it myself. It took me a weekend with Claude and continues to bring me joy.

> Caveats, stated plainly. [from the Fable transcript pasted in the article]

I had a visceral reaction to these three words.

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elahieh 22 minutes ago
"Caveats, stated plainly"

You should have seen the discussion of this on the Schneier blog a few days ago.

Someone had their agent check the solution, presumably it emailed a librarian to check that it was correct for the original edition. Then their comments read like "The BL/EEBO witness lacks it, so the discrepancy is copy-specific, not a disproof of the cipher." and "A complete 285-coordinate physical replication is still pending."

arghhhhh

https://www.schneier.com/blog/archives/2026/09/claude-fable-...

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huflungdung 10 minutes ago
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stavros 4 minutes ago
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taberiand 37 minutes ago
Anytime I get worried about where AI might be headed, I think about how Climate Change is now on its way like an out of control freight train headed straight for us, and I worry about AI a little less. I doubt it's going to do anything to us that we're not already doing to ourselves
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bluebarbet 19 minutes ago
Here's an alternative take. Climate change, and the myriad related environmental crises, are essentially a product of human population and technology. Population will follow its course, up and then down. The wildcard is technology. Yes, AI's energy hunger is worsening things right now and that's a problem. But, personally, I can't help be hopeful that AI's sheer potential might come to invert that curve. At the very least we could really use a revolutionary technology and now we may have one.
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monk_grilla 8 minutes ago
> we could really use a revolutionary technology [to address climate change]

We have it. We've had it for a long time. We've had several such technologies, take your pick: solar, nuclear, hydro, wind. The technology is not holding us back, politics, ignorance and greed are. I'm not at all hopeful AI will help us with any of those three very human flaws.

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vouaobrasil 15 minutes ago
If there is energy to be used, the system will use it because people always use power when it exists. AI can't do anything to stop it as it is both controlled by the powerful and has been trained on the tendencies of human beings to get ahead. If AI gives a person new capabilities, they'll use those capabilities selfishly, or even unselfishly but still causing harm because they're in an arms race.

We don't need a revolutionary technology. We need to experience immediate pain from reckless innovation so that we realize that innovation and tech is not the answer.

Technology only proceeds in one direction: unfettered growth, which necessitates unsustainable resource extraction. Your take is just your instinct for optimism, which in turn is just a trait that is only adaptive in primitive environments but is grossly misleading in a surplus-based society...

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gmadsen 4 minutes ago
What are you alluding to exactly and who is “we” when you say “we need to experience immediate pain from reckless innovation “
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karussell 23 minutes ago
For some reason, I’m picturing a Western right now, and climate change is a herd of wild horses coming after us. And with AI that's like robots that spur the wild horses even faster towards us...
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SwellJoe 29 minutes ago
The gas generators Elon Musk is illegally running 24/7 to run Colossus 2 (and, AI power usage in general, though some are more destructive than others) might contribute to the climate situation, though.
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KeplerBoy 14 minutes ago
might?
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_blk 31 minutes ago
What makes you say that on climate change? I was still prophesied ice ages when in high school, then 12ft water increases and sunk Maldives in university and we still have roughly the same weather.
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monk_grilla 5 minutes ago
You have entirely failed to grasp what climate change is, its effects and the timeline as described by scientists for decades.
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dhosek 23 minutes ago
Weather is not climate. Not to mention we really don’t have roughly the same weather anyway.
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voidfunc 22 minutes ago
At some point you realize theres an entire industry around climate change fear just like there's an entire industry for climate change denial.

Then you realize it never really mattered and you reach enlightenment.

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flir 53 minutes ago
I've done something similar to your formal garden map. It's work that no professional historian would ever do because the data entry would be such a slog for a relatively small reward. GPT reduced the task from "infeasible" to "annoying", and once I had the data transcribed I learned a few things, so I walked away happy. Whatever happens commercially, these models have been a real boon to hobby projects.

> I told it to look online at some of Fable’s strongest feats, especially the math problems it has solved, and that something like this should be easy in comparison.

Wait. Wait wait wait. Are we supposed to be giving them pep talks?

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bananaflag 12 minutes ago
It won't be necessary in a year when the information "AI is superhuman" in all its guises enters the training data.
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kay_o 42 minutes ago
on older gemini models ide have to actively give them encouragement and/or easy bait problems that they can correctively solve without issue to avoid runaway spiraling into "i'm useless and i want to kms" behaviour with complex use case.

I have not seen this in other models.

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Sophira 14 minutes ago
I assumed it was more because the LLM might echo an understandable human claim of "if it's been unsolved for 370 years, it's unlikely to be solved now/likely to need expert knowledge", which is probably a mindset that appears in its training data.

The LLM likely needs to be reminded of its abilities.

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lowbloodsugar 42 minutes ago
I have a very high p(doom \/ utopia) so pretty much feeling like I won’t have to worry about the future.
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SwellJoe 27 minutes ago
Given how little effort has gone into addressing climate change, doom seems more likely to me, but I doubt it'll be the autocomplete machines that do us in.
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trallnag 28 minutes ago
We have always been back
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flyinglizard 55 minutes ago
[flagged]
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ReflectedImage 48 minutes ago
That's an artifact of it not using A-Z as it's alphabet. What you type gets translated before the AI sees it. The seventeen word the AI sees does only contain three 'e' s.
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Thrymr 42 minutes ago
Is this true? If so, does it mean anything? Sure, it is tokenized in processing (tokens don't really have an alphabet either), but this means it did not correctly parse the problem at all if this is the case.
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flyinglizard 41 minutes ago
Reading your comment, I asked it to count how many characters are in the word. It answered correctly: 9. It then also said it skipped an E in the prior chat and corrected it count to 4. It spun for 52 seconds so maybe some Python was involved.
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flir 51 minutes ago
But is it smart enough to know it needs to write some Python to count for it?

That ability to create ad hoc tools makes up for a lot of shortfalls.

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GaggiX 52 minutes ago
Just tried on Astra low and it gave 4.
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mapontosevenths 47 minutes ago
I tried too. It got it. Maybe more importantly, who cares?

For example, I'm a nerd. I'm bad at baseball. I lack that kind of intelligence, even though it's more common than the ability to program. That doesn't also imply that you can't trust my Python code.

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flyinglizard 50 minutes ago
I used the 6 Pro setting in the chat. Too smart for its own good, I guess.
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cwillu 52 minutes ago
Citation needed.
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MisterMunchkin 56 minutes ago
We found a cipher my dad had written as a child with no obvious key or anything. Chatgpt was able to crack it in 20 minutes and figure out the message, and we knew it was right because it mentioned names of children he went to school with.
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mythrwy 25 minutes ago
To be fair he was a child so the cypher was likely fairly simple, maybe a Caesar cipher or similar. Cool use case though.
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amelius 29 minutes ago
> The answer was simple in hindsight. It just kept looking until it found it—and that persistence might show up in many other areas.

Sounds more like brute forcing than intelligence, this time.

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al_borland 8 minutes ago
That seems a like the result for a lot of AI solves. It solves it due to persistence, on a problem that hasn’t been important enough for a human to invest significant time into.
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trentor 22 minutes ago
There is a reason even intelligent people go back to brute force for certain problems.
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elahieh 36 minutes ago
I presume what the author did was plug Klaus Schmeh's top 50 unsolved ciphers at https://scienceblogs.de/klausis-krypto-kolumne/the-top-50-un... into Fable 5.1 and ask Fable 5.1 to have a go. On this kind of problem it always falls back to Opus 5 anyway so I save time by starting with Opus.

The successor to Klaus's blog is Satoshi Tomokiyo's Cryptiana site, so a month ago I asked Opus 5 to scrape it all, rank them and have a go at solving some. It didn't get the ranking right. But I knew the Civil War Stager ciphers were ripe for solving, so I had it do those https://cryptiana.blogspot.com/2026/09/route-transposition-c...

The art of solving historical unsolved ciphers is knowing what is on the boundary of solvability. Since this site attracts so many OpenAI and Anthropic employees, I'll mention one that was featured by both Klaus and Satoshi in 2023, presumably Spanish transposition, which should be on that boundary but has resisted all attempts at solution https://cryptiana.blogspot.com/2023/09/a-telegram-from-switz...

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Retr0id 2 hours ago
> I told it to look online at some of Fable’s strongest feats, especially the math problems it has solved, and that something like this should be easy in comparison.

Fascinating. I wonder if you could show "fake news" to a weaker model and get it to be more ambitious in its attempted solutions, even if it's not fundamentally any smarter.

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jrop 2 hours ago
I forget the story, but isn't this the origin story of one of solutions to one of the hard problems in mathematics? The story goes that the student shows up late, and misinterprets the final slide to be homework, and it turns out that the professor was showcasing a hard problem. Thinking that the slide was homework, the student takes it home and solves it.

EDIT: In 1939, George Dantzig was a graduate student at UC Berkeley studying under the statistician Jerzy Neyman. He arrived late to class one day, saw two problems written on the blackboard, assumed they were homework assignments, copied them down, and turned in solutions a few days later. He apologized for being late -- the problems had seemed "a little harder than usual."

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jonas21 50 minutes ago
Career path:

   software engineer -> prompt engineer -> positive affirmation engineer
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stbenjam 5 minutes ago
https://github.com/stbenjam/skills/tree/main/plugins/hype

I have a plug-in to do this. I don't know if it's effective but Claude said it was genuinely helpful (obviously would say that about anything)

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Yizahi 32 minutes ago
-> AI Morale, Welfare and Recreation Officer (let's be real here, heh)
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CamperBob2 29 minutes ago

    Pygmalion panderer
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ademup 2 hours ago
I really love this idea given the recent controversy around mathematics solutions. It seems like a "mere suggestion" of success has a positive impact on finding solutions. We know this technique works in humans, from which this is all derived from, so it seems to make sense.
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Aboutplants 9 minutes ago
Time to find out who Satoshi Nakamoto is
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humbleharbinger 2 hours ago
Putting all controversy aside - this is a refreshing use of a model. Models are going to be a boon in the hands of historians.
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vb-8448 40 minutes ago
> Historically, many of these problems were bottlenecked by human attention. Someone had to care enough to spend hours or days reading obscure material, testing unpromising ideas, tracing references, and trying things that might go nowhere

I wonder how many of the recent results are due to the fact that very few looked at the problem to start with. Still great results, but the general impression is that it's more about the so many low-hanging fruits than the actual capability.

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GranPC 24 minutes ago
I am trying very hard to find an original version of this cipher with no luck. It almost sounds like this whole thing is a hallucination...? Can anyone point me to a PDF of the original Cyphral Distich as printed?
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fxwin 14 minutes ago
I found this german blog: https://scienceblogs.de/klausis-krypto-kolumne/2014/11/17/we...

which links to: https://archive.org/details/s9notesqueries03londuoft/page/12...

which is in reference to the original proquiritations here: https://archive.org/details/worksofsirthomas00mait/page/416/...

i had also never heard of this before today and wonder if people had even seriously tried to decipher this at all?

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gdevenyi 60 minutes ago
Anyone pointed it at the Voynich manuscript?
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veqq 24 minutes ago
Thousands. Every day a few AI "solutions" are spammed to the relevant forums
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Diti 53 minutes ago
And at the Noita eyes. No good either.
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Avicebron 57 minutes ago
yes.
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layer8 25 minutes ago
One can wonder what Urquhart would have thought if he had learned who would be solving his cypher.
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andy_ppp 50 minutes ago
I wonder if people are getting it to help with Krypyos the final part? Great documentary on this code… https://youtu.be/jVpsLMCIB0Y
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aogaili 46 minutes ago
It is cool. But how do we know that nobody solved that problem before and it was somewhere in the training data? some blog, or some book or whatever?
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altmanaltman 40 minutes ago
Its a bit sus since there doesn't really seem to be much discourse on this either. Like okay, it solved the puzzle but the puzzle was just a key cipher with plain text? And how is this verified or even matter in terms of what it reveals? Seems more like a marketing fun post than anything susbtantial.

They published this on 31 aug and nobody in that community cared and no news covered how this 300+ years mystery was solved?

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sidewndr46 33 minutes ago
Conversely, the cipher could be so boring that no one in any academic circle bothered publishing on it.
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heaney-555 42 minutes ago
Is this going to be the cope every time this happens?
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aogaili 41 minutes ago
Haha - I'm just seriously wondering, how can anyone tell at this point?
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razster 36 minutes ago
Right, with the amount of data these models are trained on, somewhere someone may have solved it and it was in some obscure text/page no one looked at or care about. We'll probably never know.
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ares623 18 minutes ago
It's like Google without Ad/SEO incentives. All it took was trillions of dollars of investment.
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machomaster 24 minutes ago
I wonder, could current AI models solve the Zodiac killer code and how fast?
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altern8 21 minutes ago
Still can't align my navbar buttons correctly
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pluc 49 minutes ago
I'm surprised Anthropic didn't steal that announcement
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0points 48 minutes ago
AI made a zodiac-looking cipher for the headline image.
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dhosek 19 minutes ago
It’s a warning of what it’s going to do next…
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ramesh31 2 hours ago
I was watching Shatner's "Unexplained" the other day on this topic, and it hit me; there are mountains of these old mysteries out there that could be solved in an afternoon now with frontier LLMs as soon as anyone took the time to bother. Exciting times.
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Jun8 48 minutes ago
Next up: Kryptos part 4 (https://en.wikipedia.org/wiki/Kryptos)
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elahieh 31 minutes ago
Unfortunately, the totality of the evidence very much indicates that Sanborn went "buck wild" with the enciphering, he made mistake(s), or both. So this is very much in line with the Chaocipher challenge of 1990. Nice little earner for some people though.
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razster 31 minutes ago
First thing that came to mind. I imagine this has cross their minds to.
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layer8 21 minutes ago
The article mentions it.
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yuvalkarmi 55 minutes ago
now THAT is cool!
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