Comment by xkapastel | Hacker News Reader

Comment by xkapastel | Hacker News Reader

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Have you ever implemented a programming language before? You are relying a lot on "quick skims" and the POV of an "impartial reader", i.e. someone who does not know the domain. It's much easier to see through the bullshit if you're familiar with PL.

> Unlike the lambda calculus, Nock represents code as data, not data as code. This is because it is system software, not metamathematics. Its loyalties in this matter are not even slightly divided.

This does not mean anything.

> But nor is it an esoteric language or automaton, like SK combinators. Rather, Nock is a tool for defining higher-level languages - comparable to the lambda calculus, but meant as foundational system software rather than foundational metamathematics.

This is hilarious considering Nock is, in fact, esoteric. SK combinators are also very comparable to lambda calculus, and it's not clear what "foundational system software" even means in the context of a combinatory logic just like SK combinators. And why would Nock be any good at "defining higher level languages"? Keep in mind that their idea of "higher level languages" includes Hoon, another esoteric language.

You skimmed it quickly and didn't see anything that jumped out to you as wrong. That's a good explanation for how a cup and ball game like Urbit got as many users as it did: you need a bit of specialized knowledge to see that it's full of hot air.

I think you've got me wrong on this—the idea that I'm "relying" on "quick skims" and the POV of an "impartial reader," would imply that I'm somehow using these things against you. I literally am an impartial reader trying to understand this, who spent a little time reading a resource you pointed me at.

If I missed what you wanted me to discover in the resource, you could just highlight it here. But instead you've chosen to question my competence and make another series of ungrounded derogatory assertions about the tech.

Now including some mistakes, or at least overly uncharitable interpretations that are useless to an impartial reader:

> This is hilarious considering Nock is, in fact, esoteric.

It's esoteric sure, but it seems like his usage here refers to Esoteric Languages (https://en.wikipedia.org/wiki/Esoteric_programming_language) —which has a separate meaning (e.g. languages "as a proof of concept, as software art,"). That seems to be the whole point when he compares it to e.g. lambda calculus: he is maximizing practicality over mathematical elegance. So it makes perfect sense to point out that while it's esoteric it's not an Esoteric Language.

> This does not mean anything.

Again, if you take an uncharitable extreme, I agree: it's basically a meaningless thing to say. But if I wanted to be charitable I could come up with several ways of interpreting it.

> SK combinators are also very comparable to lambda calculus

Yes, I got the sense he was using them pretty much interchangeably here, using SK combinators as an example of an esoteric language, and in the next sentence he prefers "lambda calculus" because its a formal system in mathematical logic rather than a computational system, and the whole purpose of the sentence is to make a distinction between software foundations vs. mathematical foundations.

Unless you show an interest in exchanging ideas over rhetoric in your reply—don't expect any further responses from me.

You: Can you tell me why this is interesting?

Them: It's not interesting.

You: Idk this vague sentence sounds kind of interesting to me. Can you tell me why this is interesting?

Them: Trust me it's not interesting.

It seems like you jumped into the conversation part way.

Here is my actual opening:

> Just out of curiosity, have you verified in some way that your alternative is legitimate?

The entire conversation has been me trying to to get the other dude to verify (unsuccessfully) a claim he made in the opening comment.

A more accurate re-cap:

------

Them: Nock is pointless, you can just use X

Me: How do you know X would work for all Urbit's requirements?

Them: Of course it would! Nock is pointless. Read this article.

Me: I couldn't find anything in the article to support your claim.

Them: You didn't read the article correctly.

Wow...we have very different views of this conversation :)

From an outside perspective, that's really not how that conversation came across

I'm not questioning your competence, most people have not implemented a PL before. It's not a question of competence, it's a question of specialized knowledge.

> It's esoteric sure, but it seems like his usage here refers to Esoteric Languages

Yes, that's the sense that I meant it in. Nock is an esoteric language just like those others on that website.

> he is maximizing practicality over mathematical elegance.

Nock is not practical. He is certainly not maximizing practicality by making a combinatory logic that can only increment integers and then recognizing and "accelerating" a particular implementation of decrement! Let's look at Nock:

    ?[a b]           => 0
    ?a               => 1

    ^[a b]           => ^[a b]
    ^a               => (a + 1)

    =[a a]           => 0
    =[a b]           => 1
    =a               => =a

    /[1 a]           => a
    /[2 a b]         => a
    /[3 a b]         => b
    /[(a + a) b]     => /[2 /[a b]]
    /[(a + a + 1) b] => /[3 /[a b]]
    /a               => /a

    *[a 0 b]         => /[b a]
    *[a 1 b]         => b
    *[a 2 b c d]     => *[a 3 [0 1] 3 [1 c d] 
                            [1 0] 3 [1 2 3] [1 0] 5 5 b]
    *[a 3 b]         => **[a b]
    *[a 4 b]         => ?*[a b]
    *[a 5 b]         => ^*[a b]
    *[a 6 b]         => =*[a b]
    *[a [b c] d]     => [*[a b c] *[a d]]
    *a               => *a

This is what I mean by being too charitable. There is absolutely nothing whatsoever that is practical about Nock.

> because its a formal system in mathematical logic rather than a computational system

I really don't think this means anything. The lambda calculus is one of the paradigmatic computational systems, and SK combinators are closely related. And it turns out formal systems in mathematical logic are also related through the Curry-Howard-Lambek correspondence. So there's no meaningful distinction between these things.

> I think you've got me wrong on this—the idea that I'm "relying" on "quick skims" and the POV of an "impartial reader," would imply that I'm somehow using these things against you. I literally am an impartial reader trying to understand this, who spent a little time reading a resource you pointed me at.

No, what I'm saying is that, as an impartial reader, you are giving them too much of the benefit of the doubt, and also not spending a lot of time with it. There's nothing wrong with that, but it means you can get taken for a ride by people who are making a smokescreen.

Okay, I'll try to be charitable with you here and assume you've just missed this.

The problem with claims like:

> Nock is not practical. He is certainly not maximizing practicality by making a combinatory logic that can only increment integers and then recognizing and "accelerating" a particular implementation of decrement!

Is that you are evaluating a component of a larger system in isolation. The form of your argument is that this component, which is a language, has obvious deficiencies/impracticalities that can be established in terms of the language itself and how it relates to other languages.

But this doesn't take into account how the language (which is the component I spoke of) relates to the system in which it's embedded.

The appearance of impracticality is often present in foundational systems. How easy would it be do use your same form of argument and deride the Peano axioms as obviously impractical because: look how much work it is to do arithmetic with a 'successor function'—ridiculous! (i.e. the 'impracticality' depends completely on what you're trying to do with it)

This was what I was trying to investigate from the beginning: how have you verified that Nock's peculiarities don't have legitimate reasons in the context of the system of which it is a component?

If you review our conversation, you'll see that's what I was trying to figure out since my very first statement—and to this point, you have still not addressed it.

The initial poster is likely weary. I’ll try my hand exactly once. I know it can be frustrating for both parties, because sadly, to know that an expert is right, you need a bit of expertise.

Here we go.

Symmetries are useful to understand a domain. If you have one, you know that a point on the left will appear on the right. So question like “but how do you know that there really is a point on the right?” is simply because you know the proof of symmetry.

The answer to “how have you verified that Nock's peculiarities don't have legitimate reasons in the context of the system of which it is a component?” is in the same way. They mention Curry-Howard correspondence: I don’t want to lose too much time on it, but yes, it is a symmetry, so the point on the left called Nock has a corresponding point on the right called lambda calculus with the same properties; and the claims made by Nock’s author about there being no symmetry are disproved by old proofs.

In fact, there are a lot of 50-year-old systems that fulfill Nock’s goals. Since it is an old field, the majority of them had time to develop into practical systems that are much, much clearer and less esoteric.

Which brings me to the goal of Nock. Why do something esoteric when a bit of field knowledge shows the complexity is unwarranted?

One possibility is NIH.

A more likely explanation is getting users into the sunk cost fallacy. Why more likely? Because this technique has been used repeatedly by the author in other fields, like his political essays. I am not the first to have that thought; a quick Google search brings this: https://www.lesswrong.com/posts/6qPextf9KyWLFJ53j/why-is-men...

It does work. So many pixels spilt over an awkward language named after a famous anti-semite admired by the author, Albert Jay Nock.

Hi espadrine. I appreciate your well-intentioned comment, but I believe the issue here is not about grasping the symmetry argument, rather it's that the symmetry argument is not an answer to the the actual question I've been posing since the beginning.

Please correct me if I'm wrong—but the symmetry argument is basically: Nock could be classified as a concatenative combinatory logic, which is a variation of "classical" combinatory logic; this classical variation, or a particular incarnation like the SKI combinator calculus, can be viewed as a variation on the untyped lambda calculus.

That establishes an association between Nock, the alternative posted by xkapastel (which is a concatenative combinatory logic), and the lambda calculus.

So from here we can say, "why not just use the non-obscure bit of combinatory logic instead?" (we choose this over lambda calculus since Nock's approach appears concentative too, avoiding lambdas)

And my answer is that if all you need is a concatenative universal model of computation—then you're done!

But—where is it actually established that that is the only requirement for Nock in the context of Urbit? That is the question I've been asking the whole time, and which is not answered by the symmetry argument.

Nock's essential structure may be that of a concatenative combinatory logic, but that doesn't mean there aren't other aspects of its design which are important for how it relates to other particulars of the Urbit system (for instance: maybe this variation has nice performance properties in connection with other parts of Urbit—I don't know).

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