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Turing Machines on Bitcoin

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Re: Turing Machines on Bitcoin

#51

Post by nullc »

shilch wrote: post #49
nullc wrote: post #36

Earlier quoted context omitted.

What the article is describing-- explicitly unrolling operations in advance and checking them in script-- has always been possible in Bitcoin and doesn't have anything to do with Turing completeness. It's only being promoted as something new or inventive as an element of a very strange con.

This is not at all what this article describes. You're making the same mistake as truth_machine does: The loop unrolling is not part of the proof but just an implementation detail for the transition lookup; it could as well have been a large if-else. The actual looping / transitioning is implemented via bitcoin transactions which is a new technique that was only recently developed.

> The loop unrolling

Unrolling once is still what I'm referring to there.

> a new technique that was only recently developed.

That's simply false. E.g. search for 'covenant' or 'recursive covenant'. It's also described on the mailing list as far back as 2011.

(And, incidentally, the first example of a turing complete machine controlling the release of a transaction on Bitcoin was in 2016 and was vastly more efficient and private than the the approach used by the post-- https://bitcoincore.org/en/2016/02/26/zero-knowledge-conting... )

Re: Turing Machines on Bitcoin

#52

Post by shilch »

nullc wrote: post #51
shilch wrote: post #49

Earlier quoted context omitted.

This is not at all what this article describes. You're making the same mistake as truth_machine does: The loop unrolling is not part of the proof but just an implementation detail for the transition lookup; it could as well have been a large if-else. The actual looping / transitioning is implemented via bitcoin transactions which is a new technique that was only recently developed.

> The loop unrolling Unrolling once is still what I'm referring to there. > a new technique that was only recently developed. That's simply false. E.g. search for 'covenant' or 'recursive covenant'. It's also described on the mailing list as far back as 2011. (And, incidentally, the first example of a turing complete machine controlling the release of a transaction on Bitcoin was in 2016 and was vastly more efficient…

The proof in the article is not about unrolling.

Whatever I read regarding "covenant" requires a protocol change. Independent of who described the underlying technique first, this doesn't invalidate the proof.

Re: Turing Machines on Bitcoin

#53

Post by mpapec »

truth_machine wrote: post #20

So it looks like a better title would have been "saving the state of the turing machine on the bitcoin blockchain", as the claim of Turing completeness[1] seems disingenious - bitcoin script itself has no looping constructs and is decidedly non turing complete. The user has to call the contract as many times as necessary to ensure that Turning machine transitions between states, and the same user checks that the comp…

Looping is not required to qualify as a Turing machine, and it never was. Bitcoin intentionally doesn't have loops, and higher level language sCrypt offer just that.

Re: Turing Machines on Bitcoin

#54

Post by nullc »

shilch wrote: post #52
nullc wrote: post #51

Earlier quoted context omitted.

> The loop unrolling Unrolling once is still what I'm referring to there. > a new technique that was only recently developed. That's simply false. E.g. search for 'covenant' or 'recursive covenant'. It's also described on the mailing list as far back as 2011. (And, incidentally, the first example of a turing complete machine controlling the release of a transaction on Bitcoin was in 2016 and was vastly more efficient…

The proof in the article is not about unrolling. Whatever I read regarding "covenant" requires a protocol change. Independent of who described the underlying technique first, this doesn't invalidate the proof.

> The proof in the article is not about unrolling.

Sure it is. The state machine expressed in the script checks one (or more) steps of the update rule. That's what we mean by unrolling, not the "or more" part but the fact that the script is just running a simple circuit for a fixed operation.

> doesn't invalidate the proof

Proof of what? It's not a proof of script being turing complete. If you're claiming that it's that-- it's invalid on its face.

If you're saying it's a proof that script can implement a static state machine that runs one or more steps at a time checking some transcript computed by an external process and check consistency of state using the outputs-- then sure, that's not news, nor controversial, it's been known almost all of the system's life.

Re: Turing Machines on Bitcoin

#55

Post by mpapec »

nullc wrote: post #44
wildsatchmo wrote: post #43

Earlier quoted context omitted.

You're conflating (intentionally?) Bitcoin the system vs Bitcoin Script. Nobody claims the Script in a vacuum is Turing complete which is important and by design, including the article which clearly says "Each step in running the Turing machine is triggered by a Bitcoin transaction." Others have explained this too, so forgive me if your account age combined with Greg's precense, your arguments style, and the very pec…

Wright himself has claimed many times that Script itself is turing complete-- in fact that is the thesis of the almost entirely plagiarized “A Proof of Turing Completeness in Bitcoin Script”, an analysis of which is linked in my long comment here. Certainly the article linked here appears to try to cause the reader to believe the same thing. > The concept of a Turing machine has been well defined. It would be suffici…

> The claim that I'm operating other accounts here isn't just unfounded, it's malicious defamation

Actually you have been caught at least once in sockpuppeting, so it's not a defamation rather a possible and realistic scenario which shouldn't be dismissed.

https://archive.ph/472MO

Re: Turing Machines on Bitcoin

#56

Post by dang »

sumeno wrote: post #3

This is the perfect representative of blockchain technology because it’s a convoluted way to do something that is better done with existing technologies without using a blockchain.

"Please don't post shallow dismissals, especially of other people's work. A good critical comment teaches us something."

https://news.ycombinator.com/newsguidelines.html

Re: Turing Machines on Bitcoin

#57

Post by nullc »

mpapec wrote: post #55
nullc wrote: post #44

Earlier quoted context omitted.

Wright himself has claimed many times that Script itself is turing complete-- in fact that is the thesis of the almost entirely plagiarized “A Proof of Turing Completeness in Bitcoin Script”, an analysis of which is linked in my long comment here. Certainly the article linked here appears to try to cause the reader to believe the same thing. > The concept of a Turing machine has been well defined. It would be suffici…

> The claim that I'm operating other accounts here isn't just unfounded, it's malicious defamation Actually you have been caught at least once in sockpuppeting, so it's not a defamation rather a possible and realistic scenario which shouldn't be dismissed. https://archive.ph/472MO

That claim is utterly false. All you're effectively doing is saying that someone has maliciously defamed me before and so it's okay to write more of it. It's not. Cut it out.

The person that page accuses of being me is a well known, highly respected community member with a decade long extremely high volume history who is utterly distinct from me-- and whos interest don't overlap mine significantly (outside of Bitcoin and the Craig Wright scam). Moreover, Wright previously admitted that contrarian__ is not me.

[Aside, mpapec is an account Craig Wright has previously used to evade his ban on HN: https://news.ycombinator.com/item?id=21978954 --- perhaps Wright out spend some time responding to his pathetic lawsuit against me instead of delaying his response and harassing me online.]

Re: Turing Machines on Bitcoin

#58

Post by mpapec »

nullc wrote: post #57
mpapec wrote: post #55

Earlier quoted context omitted.

> The claim that I'm operating other accounts here isn't just unfounded, it's malicious defamation Actually you have been caught at least once in sockpuppeting, so it's not a defamation rather a possible and realistic scenario which shouldn't be dismissed. https://archive.ph/472MO

That claim is utterly false. All you're effectively doing is saying that someone has maliciously defamed me before and so it's okay to write more of it. It's not. Cut it out. The person that page accuses of being me is a well known, highly respected community member with a decade long extremely high volume history who is utterly distinct from me-- and whos interest don't overlap mine significantly (outside of Bitcoin…

> That claim is utterly false.

Can you repeat that using some of sock accounts?

It would appear more convincing if coming from puppets too. :)

Re: Turing Machines on Bitcoin

#59

Post by someonewhocar3s »

1. The miners don't run your code 2. The network has no incentive to run your code 3. You are interpreting your code (original sw ignores it)

Having a third party app checkpoint and do TX to log that is operationally the same. A hash does anchor what's from very well.

I'd therefor avoid arguing 'bitcoin is turing complete'. Somehow I feel they're arguing it doesn't matter. I also note the lack of a Bitcoin opcode sample. "Ramming Memory in to BTC" is as far as they went.

Re: Turing Machines on Bitcoin

#60

Post by midmagico »

wildsatchmo wrote: post #45
nullc wrote: post #44

Earlier quoted context omitted.

Wright himself has claimed many times that Script itself is turing complete-- in fact that is the thesis of the almost entirely plagiarized “A Proof of Turing Completeness in Bitcoin Script”, an analysis of which is linked in my long comment here. Certainly the article linked here appears to try to cause the reader to believe the same thing. > The concept of a Turing machine has been well defined. It would be suffici…

Here is CSW's original claim that Bitcoin is Turing complete that took many by surprise including Nick Szabo. They heard it as you did, specifically addressing Bitcoin Script. He immediately corrects them: "The difference is that the SCRIPT ITSELF ISN'T, what you can do is..." So there you go. Clearly not what you're claiming here, and if he said anything similar casually I'm sure this is exactly what he means, as he…

You knew this already. Also, Craig's defending the claim using statements about Forth-likeness, which is the same thing he insists Bitcoin script is because magic-of-a-second-stack. Additionally, he re-iterated the exact claim that Bitcoin script itself is Turing complete with the assistance of Ian Grigg. Ian references often a paper asserting it is so, which I and two or three others completely refuted as nonsense, since the paper itself actually references another blockchain entirely which itself has looping constructs, but then Ian, Craig et al make the absurd claim that because it this other blockchain's script is "Bitcoin-like" then Bitcoin itself is therefore also Turing complete.

But then he also wrote a paper asserting that Bitcoin script is Turing complete:

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3265157

In other words, it's layers of bullshit all the way down.

By the way, just for fun, Craig Wright also made the absurd assertion that the second stack can be used to create constructs that can't be implemented with a single stack, so he's stupid in that sense, too, as I demonstrated with a single sequence of single-stack opcodes which accomplishes the exact same thing he stupidly asserted couldn't be done.

https://twitter.com/midmagic/status/924844200645902336

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