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Re:Navier–Stokes Lost in Translation by FrustratedMonky on Wednesday October 07, 2026 @12:39PM (#49995224)
Not a mathematician. Why not just always use LEAN? Why use natural language at all?
Re:Navier–Stokes Lost in Translation by ted_dunning on Wednesday October 07, 2026 @12:45PM (#49995318)
Because it is really hard to read and the level of detail is so high that even lemmas that you can read may have such enormous levels of detail that makes real understanding difficult given that humans have limited working memory.
Re:Navier–Stokes Lost in Translation by matusp on Wednesday October 07, 2026 @12:46PM (#49995340)
Why not always write machine code? Why use programming languages at all?
Re:Navier–Stokes Lost in Translation by FrustratedMonky on Wednesday October 07, 2026 @02:31PM (#49996912)
If a programming language compiler isn't guaranteed to be re-producible, then yeah, you'd have to revert to machine code.
Re:Navier–Stokes Lost in Translation by coafos on Wednesday October 07, 2026 @07:05PM (#49999973)
The same JavaScript code compiles to different machine representations under different browser engines; yet webdevelopers don't need to learn assembly.

There is an abstract javascript machine which can obviously be translated to hardware instructions. "Obvious" in the mathematical research sense, as in the statement is flat out wrong under closer inspection. Websites regularly crash under memory pressure.

But they are good enough most of the time, and that's the key. With more resource a more correct program can be created, but cost-benefit calculations show a ceiling. A local pet store does not have the money to pay 2000 hours of formal verification work, and usually a WordPress site is good enough.

Mathematicians work with their brains. They have finite time to understand papers. Formalists say that all theorems could be reduced to logical axioms, but most of time it's jumping at a much higher level, because no one has time for minute details. Proofs are theoretically right or wrong, but in practice there are "slightly wrong" proofs, where there are some minute errors that "feels" like can be correcte, and most of the time it can be. This ambiguity is not a problem, but a feature of mathematics, because it means more time can be spent to move faster at a higher level of abstraction, but this would be lost with Lean.

Re:Navier–Stokes Lost in Translation by FrustratedMonky on Thursday October 08, 2026 @07:36AM (#50004601)
Isn't that the joke with Fermat's last theorem?

That he jotted in a margin that he had just seen a simple proof, and would write it down later. And we spent a hundred years trying to reproduce.

Or some other joke about a mathematician will put "and here we see it simply follows" or some such.

I'm all for abstraction, I get the point.

But for natural language it seems like " I saw my ex boyfriend last night and, yada yada yada, I'm really exhausted this morning".

See, the yada-yada is a bit too much abstraction.

I took the problem like this:

If we treat each human as a compiler of natural language, and there is enough ambiguity that each human arrives at a different result. Then is it really a proof?

Guess I'm missing the point of the paper, I thought it was trying to show that natural language is flawed and formalized systems are better.

And AI is getting tripped up by the human ambiguous natural language.

Re:Navier–Stokes Lost in Translation by matusp on Thursday October 08, 2026 @12:32AM (#50001831)
There are bugs found in programming language implementations all the time. I guess you are switching to machine code, good luck.
Re:Navier–Stokes Lost in Translation by FrustratedMonky on Thursday October 08, 2026 @07:31AM (#50004551)
Yeah, and if you re-run the same program with the same bug, it will fail the same way each time. It is reproducible. What are you even trying to argue about?

If we treat each human as a compiler of natural language, and there is enough ambiguity that each human arrives at a different result. Then is it really a proof?

Re:Navier–Stokes Lost in Translation by matusp on Thursday October 08, 2026 @02:42PM (#50010151)
> Yeah, and if you re-run the same program with the same bug, it will fail the same way each time.

[Citation needed]

Re:Navier–Stokes Lost in Translation by FrustratedMonky on Thursday October 08, 2026 @05:56PM (#50012964)
Citation

2 + 2 = 5 -> Error

Every time.

Re:Navier–Stokes Lost in Translation by FrustratedMonky on Friday October 09, 2026 @08:51AM (#50019766)
Got to thinking maybe you were still in school and hadn't covered determinism yet. Here is old school stack overflow answer that is short and clear.

The environment does matter. I think in your original objection, you were executing the code in different environments.

https://cs.stackexchange.com/questions/38152/what-is-determi...

And to the point of the original article. Each human interpreting natural language is a new environment. Each brain is a new compiler with different outcomes. Thus the ambiguity. Natural language isn't concrete enough to always have the same result when processed by different humans, or AI.

Re:Navier–Stokes Lost in Translation by matusp on Sunday October 11, 2026 @01:06PM (#50045368)
The top reply is already all you needed:

> the answer with many multi-threaded programs is often "no."

Re:Navier–Stokes Lost in Translation by FrustratedMonky on Monday October 12, 2026 @10:28AM (#50056957)
And, nobody would correct them? If a programs output is random, what use is it.

Isn't the original point, that natural language isn't sufficient for proofs? Aren't you agreeing now?

Re:Navier–Stokes Lost in Translation by Jtarii on Wednesday October 07, 2026 @12:47PM (#49995354)
Lean is a write only programming language.
Re:Navier–Stokes Lost in Translation by jansport123 on Wednesday October 07, 2026 @12:43PM (#49995297)
Same reason humans write code not only for a compiler to translate into machine code but also so other humans can understand what we write, learn from it, modify it etc...
Re:Navier–Stokes Lost in Translation by Jaxan on Wednesday October 07, 2026 @12:48PM (#49995367)
Not only that, we also have code comments and standalone documentation.
Re:Navier–Stokes Lost in Translation by FrustratedMonky on Wednesday October 07, 2026 @02:34PM (#49996958)
A programming language, when compiled, is a guaranteed reproducible result. If you recompile a program, you get the same thing each time.

The point of the article is that natural language is not these things.

Re:Navier–Stokes Lost in Translation by binlog on Wednesday October 07, 2026 @12:44PM (#49995306)
Because people need to understand what is being proven.
Re:Navier–Stokes Lost in Translation by caughtinthought on Wednesday October 07, 2026 @12:56PM (#49995502)
The example in Figure 1 should help understand why... the NL version is much more approachable for humans.
Re:Navier–Stokes Lost in Translation by FrustratedMonky on Wednesday October 07, 2026 @02:45PM (#49997099)
If its ambiguous or wrong, then what are you understanding ?
Re:Navier–Stokes Lost in Translation by upboundspiral on Wednesday October 07, 2026 @02:57PM (#49997264)
Is not a natural language (NL) proof a demonstration of mastery and understanding?

If you understand the Lean, then you can create a NL proof. The LLM clearly doesn't understand the Lean code it produced.

Re:Navier–Stokes Lost in Translation by FrustratedMonky on Thursday October 08, 2026 @07:33AM (#50004567)
I guess I misunderstood the paper, that natural language proofs are not mastery/understanding because they can be ambiguous, miss-interpreted. Natural language can be misinterpreted enough that it is not a given to be correct. And AI was misinterpreting what a human meant in the ambiguous natural language.