Ultimately, as always, credit will be assigned by future generations of scientists and historians long after everyone who is alive today has disappeared from the face of the earth. Many disagreements that seem important now will be forgotten. Many findings that seem important now will turn out not be. Many names that are very prominent now will fade into obscurity. As always.
[a] https://people.idsia.ch//~juergen/deep-learning-conspiracy.h...
[b] https://www.nytimes.com/2016/11/27/technology/artificial-int...
So, he has
>Ultimately, as always, credit will be assigned by future generations of scientists and historians long after everyone who is alive today has disappeared from the face of the earth.
Well, credit for the field of CS is already applied now, and also yesterday and 20 years ago. It's not like this future credit would be the first such, or that it would be more accurat (or that it would not feed of the current popular views).
~ Sir Thomas Browne, Hydriotaphia (1658)
But that downplays her accomplishments too much. She didn't write the "first program" but she was the first to understand what computers would be capable of doing (for example, that by assigning numbers to letters and symbols, computers could do more than simply perform numerical computations), and she was the first to invent foundational control flow structures such as loops and conditionals. Her program was much more rigorously defined and sophisticated than any previous examples.
>The longest program that Menabrea presented was 11 operations long and contained no loops or branches; Lovelace’s program contains 25 operations and a nested loop (and thus branching).
https://twobithistory.org/2018/08/18/ada-lovelace-note-g.htm...
https://writings.stephenwolfram.com/2015/12/untangling-the-t...
https://projectlovelace.net/static_prod/img/Diagram_for_the_...
https://writings.stephenwolfram.com/2015/12/untangling-the-t...
I very much recoginized from that that she had the attitude and experience of a "programmer," so I would say she was the first programmer, in the modern sense.
The Analytical Engine has no pretensions whatever to originate anything. It can do whatever we know how to order it to perform. It can follow analysis; but it has no power of anticipating any analytical relations or truths. Its province is to assist us in making available what we are already acquainted with. This it is calculated to effect primarily and chiefly of course, through its executive faculties; but it is likely to exert an indirect and reciprocal influence on science itself in another manner. For, in so distributing and combining the truths and the formulæ of analysis, that they may become most easily and rapidly amenable to the mechanical combinations of the engine, the relations and the nature of many subjects in that science are necessarily thrown into new lights, and more profoundly investigated. This is a decidedly indirect, and a somewhat speculative, consequence of such an invention. It is however pretty evident, on general principles, that in devising for mathematical truths a new form in which to record and throw themselves out for actual use, views are likely to be induced, which should again react on the more theoretical phase of the subject. There are in all extensions of human power, or additions to human knowledge, various collateral influences, besides the main and primary object attained." -- Ada Lovelace, 1842 http://www.fourmilab.ch/babbage/sketch.html
I learned about it in Walter Isaacson's Innovators.
That almost sounds to me like saying that the Wright brothers "made a few simple flights".
> first to invent foundational control flow structures such as loops
I wonder how sigma notation fits into this. Clearly the notion of expressing arbitrarily repeated operations using a fixed amount of information (which is what a loop is, essentially) was known at least to Euler.
Also, the fact that the machine enabled these things in the first place (unlike even some of the later machines such as Z3) suggests that its designer was either aware of this necessity to begin with, or at the very least in possession of preternatural prescience. In that case the use of these features in some programs but not in others would be not a matter of inventing them in the former programs but instead a matter of choosing to exploit existing hardware features, or declining to do so, depending on what program you're looking at.
You can even go further back. Algorithms with loops were known already to Babylonian mathematicians. So you don't need to resort to preternatural prescience.
The Z3 was not intended as a general computing device but as a practical help for engineers. Because of that you can't say it was missing something it didn't need to do its job. Whereas when Zuse designed Plankalkül loops and conditional branches where naturally included in the design.
Richard Pearse gets written off in the same way to elevate the Wright brothers flying accomplishments.
Pearse was just perusing powered flight as hobby in rural New Zealand, didn't bother informing the press and didn't bother even telling the government until WWII, 40 years later, about his flights and engineering designs.
Maybe the first programmer who wasn't also a hardware engineer.
That said, I'm sure in the case of Ada Lovelace there is at least some element of my misogyny involved.
Or merely the first to express it? I'm pretty sure Babbage himself, as the inventor, understood well what computers would be capable of doing.
From TFA:
> There is a seemingly minor difference whose significance emerged only later. Many of Gödel's instruction sequences were series of multiplications of number-coded storage contents by integers. Gödel did not care that the computational complexity of such multiplications tends to increase with storage size. Similarly, Church also ignored the context-dependent spatio-temporal complexity of the basic instructions in his algorithms. Turing and Post, however, adopted a traditional, reductionist, minimalist, binary view of computing. Their machine models permitted only very simple elementary binary instructions with constant complexity, like the early binary machine model of Leibniz (1679)[L79][LA14][HO66] and Zuse's 1936 patent application...
I presume by "seemingly minor" Schmidhuber implies "it turns out to be very important".
To echo my other comment here, it’s not that Church himself knew that. Even five years ago people did not know that. It’s not a question of priority. But I find it fascinating and reassuring nevertheless, as actually programming e.g. a self-interpreter for a Turing machine—or for general recursive functions, or for combinatory calculus—is an absolute slog.
Dal Lago, Martini (2008). “The weak lambda calculus as a reasonable machine”. DOI:10.1016/j.tcs.2008.01.044, apparently not on arXiv.
Accattoli (2012). “A fresh look at the lambda-calculus”. DOI: 10.4230/LIPIcs.FSCD.2019.1, apparently not on arXiv.
Accattoli, Dal Lago (2014). “Beta reduction is invariant, indeed”. DOI: 10.1145/2603088.2603105, arXiv: 1405.3311 [cs.LO].
Accattoli, Dal Lago (2016). “(Leftmost-outermost) beta reduction is invariant, indeed”. DOI: 10.2168/LMCS-12(1:4)2016, arXiv: 1601.01233 [cs.PL].
Forster, Kunze, Roth (2020). “The weak call-by-value lambda-calculus is reasonable for both time and space”. DOI: 10.1145/3371095, arXiv: 1902.07515 [cs.CC].
Now that I’m looking through bibliographies, there are apparently other relevant intervening papers in the vicinity, even by some of the same authors, but these are what I’ve looked at personally.
Bonus: the paper
Hackett, Hutton (2019). “Call-by-need is clairvoyant call-by-value”. DOI: 10.1145/3341718, apparently not on arXiv.
is unrelated to questions of complexity but is just so absolutely lovely.
> Nevertheless, according to Wang,[WA74-96] it was Turing's work (1936) that convinced Gödel of the universality of both his own approach (1931-34) and Church's (1935).
Unless "according to Wang" is meant as "I don't know if I believe it", then apparently it's documented that Godel himself thought Turing's contribution was major and shed important light on the mathematical implications of godel's own work.
There's never any one person that invents anything, it's always built on work that came before.
Reading the OP, I got increasingly bored and tired... ok, what's your point? Yes, clearly Godel and Church especially did foundational work without which Turing's work would not be possible -- and I don't think anyone denies it, anyone with any kind of computer science education is surely familiar with Godel and Church. It's not like they are languishing in obscurity, they are both very well known and respected! Godel especially is widely considered a real giant in his fields. I am as confident that neither Godel nor Church is going to be forgotten for many generations.
But Turing made important contributions that took important steps necessary for the development of CS as a field. It's not a mystery or undeserved why Turing's name ends up remembered.
The OP's point is just that any singular "inventor" is always building on work of may who have come before? OK, sure. Boring. So we should never promote anyone as making important foundational contributions? Well, people aren't gonna stop. Boring.
It is difficult to get a man to understand something when his salary depends upon his not understanding it.
But wait a minute, you might say, facts are facts.
And if everyone had the time and resources to discover and digest every fact, your understanding would be the end of it.
But everyone doesn't have time and resources. To compensate, we rely on others to curate facts for us. When we encounter an internally consistent subset of facts that suits our ideals and our interests, we adopt that point of view.
There are infinitely many subsets of curated facts that can be presented as internally consistent. That's why there are so many different points of view.
What bearing does this have on Turing's role in computer science, and his latter day fame in a society which came to be defined by silicone logic?
The First Computers Were Human (and Mostly Women)
https://mjosefweber.medium.com/the-first-computers-were-huma...
Turing, in addition to stating an ontology of computing, dared to invite the question, what is the difference between a computer and a human?
I cringe when I read ill-researched essays like these because it informs a relationship between women and computing that back then genuinely did not exist.
For the vast, vast majority of women in the field of computing at this time, they were nothing more than glorified calculators. Yes, there were a few women scientists and mathematicians (by few, I mean literally handfuls). Yes, it was a male dominated field.
But the overwhelming majority of women working in this industry at this time did secretarial style busywork. It wasn't glorious. It was underappreciated. It sucked.
These types of essays are a genuine attempt to rewrite a history that did not exist. It is literary gaslighting the likes of which the article we are discussing right now is attempting to rectify.
I'm not sure what you are saying? Could you clarify?
What is "secretarial style busywork"?
Is this article also "ill-researched"?
https://www.smithsonianmag.com/science-nature/history-human-...
What would a better researched view of history say?
I'm not trying to troll you or make you write an essay here - just trying to glean the main points of what you believe so I can see your point of view.
Are you familiar with the view that the "Turing Test" was first conceived by Turing as a challenge to discern the gender of a human hidden behind a screen?
In my comment I was trying to point to Turing's interests in the nature of gender and humanity. I find that expansive and prescient in the sense that "computing" to us moderns is more about NLP than calculating maths, and yet, it's all the same thing under the hood.
There’s also the point (mentioned e.g. by Wadler in his “Propositions as types” talk) that Gödel didn’t actually realize how pervasive universal computation was and actively pushed back against Turing proclaining the equivalence. This is not to accuse him—he wasn’t particularly obstinate or unfair about it and, furthermore, came to understand the idea fairly quickly. But it’s not at all uncommon in science for the one who actually invented a thing to fail to realize what it was that they just invented, and somebody else comes years or in some unfortunate cases decades later and announces the founding of a new area of knowledge on that already-discovered site. Whom the later naming will associate with the discovery is a toss-up, but it’s generally fair and in good taste, I think, to mention both.
So your argument is, because it is unclear how to "physically implement the arbitrary-function minimization operator", Turing is the better "theoretical backbone" and has founded computer science?
Church had piles of stuff that he and his students produced that were computable with the lambda calculus. Basically, all of the natural number functions that a person thinks are intuitively mechanically computable, those folks had showed how to lambda compute. With this evidence, he proposed to Godel (they were working together at Princeton at the time), who was considered the world's expert, taking "lambda-calculable" as a mathematically precise version of "mechanically computable." But Godel was notoriously careful, and he did not accept the thought as perfectly clear.
That is, they had a subset of the things that could be mechanically computed. But was it the entire set? Or was there something that some discrete and deterministic mechanism could be made to do that would lead to more than Church's set?
Imagine you are Dedekind and you are looking at the primitive recursive functions and (1) any such function is intuitively mechanically computable, and (2) you are able to work out how to define a pile of things like prime factorization of an integer using this system. You might well conjucture that this is it. But we know (and Godel and Church and Turing knew) that this is not it, that you need to add unbounded search of some kind (this is what minimization does) to get more things that are intuitively mechanically computable.
I agree that the minimization operator is not as easy to picture with gears and levers as some of the other operations. But the issue in 36 was that a person could worry that there was even more. Just as minimization is not as easy to picture and the need for it didn't hit Dedekind with great force, could there be something else out there that we have all missed?
That worry disappeared when Godel read Turing's masterful analysis. It convinced him that this is what a machine can do. He wrote, "That this really is the correct definition of mechanical computability was established beyond any doubt by Turing.'' Church felt the same way, writing that Turing machines have "the advantage of making the identification with effectiveness ... evident immediately.''
Yes, the set of functions computable with mu recursion, or with lambda calculus, is the same as the set of functions computable with a Turing machine. (Turing in his original paper showed that the set is the same for his system and Church's, and the proofs for mu recursion and many other systems are well-known.)
> I'll totally agree that from a teacher's perspective, the Turing machine is the better explanation.
When I learned this, the instructor did not use Turing machines. They used mu recursion. That has the advantage that you don't first define a machine and then derive the set of functions, instead you go straight to the functions. But I agree that Sipser (which I understand to be the most popular text today) defines a computable function as one that is computed by Turing machine, and to my mind that has the advantage of honestly suggesting to students what they are about.
It does seem weird to me though that we're letting our engineering limitations determine how we think about these things mathematically.
Turing machines do have mathematical advantages in some areas. See this siblings comment: https://news.ycombinator.com/item?id=28541800
The Rekursiv advantage is its ability to do recursion on the bare-metal. It's described as an object-oriented architecture. Its memory was a persistent store of objects, with each object having its size, type, and position known in memory.
I came into programming/computer science from a mathematics degree; I read some old treatises on recursion theory[1] and fell in love. I couldn't ever quite wrap my head around the Turing Machine formalism, but kept at it for a while. Finding Barendregt's paper [2] was a huge shock! I grasped it much quicker. So, yes, lambda calculus and the Turing Machine formalism are equivalent in explanatory power, but there are also reasons someone might prefer one to the other. So, yes, for me, the value _is_ the formalism.
As to why I think the Rekursiv would provide a good platform for implementing lambda calculus on the bare-metal, that's entirely due to Rekursiv's memory model advantage and the fact that it has a user-writable ISA. Why would someone choose to implement the lambda calculus on bare-metal? You call it "fetishism," I call it fun!
More generally, I just really like the idea of having a machine with a user-writable ISA.
[1] Theory of Recursive Functions and Effective Computability: https://openlibrary.org/books/OL2738948M/Theory_of_recursive...
[2] Introduction to Lambda Calculus: https://www.cse.chalmers.se/research/group/logic/TypesSS05/E...
Thanks for clearing up that it's the formalism you find interesting. Also, to offer a counterpoint, I'm also from a math background, but I was more of an analysis person (as much as one can be in mathematics where it's all related) than an algebra person, and when I did some FP research, it often felt like where all the algebraists go to play computer science. I feel like analysts are underrepresented in PLT (and overrepresented in complexity theory!) but this is already going off-topic, so cheers.
Out of curiosity, can you identify any areas in PLT that could be made more analyst-friendly?
Intuitively, it feels that PLT is almost necessarily of the algebraist; to me, one of the big divides is the discreteness of algebra vs the continuity of analysis. Would it help if there was a PLT that exhibited a greater degree of continuousness? If so, what do you think that might look like?
That's also a very interesting perspective on analysis. To get a better feel: is your joy of analysis in getting into the "internals" of an algebra, to directly derive properties of elements within the algebra as opposed to relying solely on global properties endemic to the construction of the algebra?
I'd also love to see your talk! Do you think a RISC Rekursiv could be achieved? What value, if any, do you think such might have in our current world?
http://www.wolczko.com/mushroom/
The slides for my 2019 talk about Smalltalk computers (in LibreOffice and PDF formats):
http://www.merlintec.com/download/2019_slides_jecel_fast1v2....
http://www.merlintec.com/download/2019_slides_jecel_fast1v2....
and the video (1 hour and 13 minutes):
https://www.youtube.com/watch?v=tATpzsyC6OA
If you replace the Rekursiv's special microcode memory with a cache to allow microcode to live in main memory you will essentially have a RISC version of the machine. I have adopted this solution in several of my own designs.
I'm also deeply in love with the merlintec website. It's refreshing to see a website which has persisted since 1999(!), and without a lick of JavaScript it would seem!
Could I purchase a Merlin 6 or a Pegasus 2000?
Speaking of which, the way that the Pegasus 2000's eGUI documentation[1] is written is incredibly dear. The "world" and "heaven" analogies are great!
If I may ask, from your perspective, what's more elegant about Rekursiv's design? Is it the philosophy or implementation? I'd also love any links to orthogonal persistence!
That theory continues to bear fruit as the history of programming languages is almost entirely about bringing new and "better" abstractions to problems and then translating them to "dumber, more practical" machines. We have programming languages today modeled directly off the elegance of (though now sometimes still a few steps removed from being direct implementations of) the lambda calculus and mu-recursive functions, and the amazing thing is that they work great even given how "dumb" and "inelegant" our machines can be in practice.
See also https://en.wikipedia.org/wiki/Church%E2%80%93Turing_thesis
This is already proven to be the case. Mu-recursion (which IIRC is not Godel's general recursive functions, despite what Wikipedia says; Kleene was the originator of the mu operator. Godel's general recursive functions are defined in a separate, but yet again equivalent way that directly extends primitive recursion), Turing machines, and the lambda calculus are all proven to be exactly equivalent to each other. The fact that these three independent approaches to computability are all equivalent is why we have strong informal justification that the Church-Turing Thesis (a non-mathematical statement) holds.
Separately, there's a sentiment that I've seen come up several times on HN that somehow the lambda calculus, mu-recursion, or general recursion is more "mathematical" and Turing machines are less "mathematical."
I want to push back on that. The mathematical field of computability is based almost entirely off of Turing machines because there are many classes of mathematical and logical problems that are easy to state with Turing machines and extremely awkward/almost impossible to state with the lambda calculus and mu-recursion (this is consistent with my previous statement that the three are all equivalent in power because computability theory often deals with non-computable functions, in particular trying to specify exactly how non-computable something is). The notion of oracles, which then leads to a rich theory of things like Turing jumps and the arithmetical hierarchy, is trivial to state with Turing machines and very unwieldy to state in these other formalisms.
Likewise the lambda calculus and mu-recursion (but not general recursion) provide a very poor foundation to do complexity theory in CS. Unlike Turing machines, where it is fairly easy to discern what is a constant time operator, the story is much more complicated for the lambda calculus, where to the best of my knowledge, analyzing complexity in the formalism of the lambda calculus, instead of translating it to Turing machines, is still an open problem.
There is indeed a mathematical elegance to Turing machines that makes it so that most of the mathematics of computability is studied with Turing machines rather than the lambda calculus.
The lambda calculus on the other hand is invaluable when studying programming language theory, but we should not mistake PLT to be representative of the wider field of mathematics or theoretical CS.
EDIT: I should perhaps make clear that if I put on my mathematical hat, mu-recursive functions seem like the most familiar formalism, because they align with a common way families of things are defined in mathematics (specify individual members and then generate the rest through some relationship). However, I would contend that for the majority of mathematicians outside of computability theory, the lambda calculus and Turing machines seem equally "strange."
However, yes, I do think that 'mechanization' or physical implementation is a crucial piece of Turing's contribution that is wrongly ignored in this article. And I think without mechanization, there is no CS as we understand it.
"Likewise, Konrad Zuse never got a Turing award despite having created the world's first working programmable general computer 1935-41. [...] It was pointed out that none of the computers built during the 1940s were influenced in any way by Turing's 1936 theoretical paper, [...]"
In my view, Turing's contribution is providing a plausible definition of computation along with a deep and comprehensive theoretical characterization of the properties of this model of computation. This is why Turing machines form the basis of theoretical computer science, and not other models such as lambda calculus. I think saying that Turing machines were adopted since they were merely more convenient is highly misleading.
I think this pattern repeats a lot: There are many cases where you can point to multiple people who invented similar ideas around the same time, but it is typically the person who provided the most deep and comprehensive treatment of the subject that ultimately gets most of the credit. This depth is not conveyed in pop science attributions such as "Turing invented computation", but this doesn't mean Turing doesn't deserve the credit.
His Turing award citation: "Professor Wilkes is best known as the builder and designer of the EDSAC, the first computer with an internally stored program."
The 2009 award to Chuck Thacker, on the other hand, was clearly based on his contributions to hardware. I have the impression that ACM had a change in policy around that time.
But officially I seem to be wrong:
https://amturing.acm.org/bysubject.cfm?cat=16 https://amturing.acm.org/bysubject.cfm?cat=15
In the "hardware" category Wilkes is listed as the only one, while Thacker, with Brooks, Cocke and Wilkes are in the "computer architecture" category.
The word computer means multiple things. In one sense it the abstraction of universal computation. Imagine a world where actual physical computers didn't progress to universal computation, but were stuck being purpose built to the present day. The field of computer science would be utterly different because they couldn't actually compute anything with their science. They could just discuss computability in an abstract sense. It'd be like physics without the particle colliders or telescopes or lasers.
I think of the founders of computer science more like the founding fathers of America, rather than a single guy named Turing, but some are more memorable than others.
It’s not clear that you need a theory of computation to build a stored process computer. You might not clearly understand the theoretical capability of such a machine , but that wouldn’t prevent you from doing many useful things with it.
"Likewise, Konrad Zuse never got a Turing award despite having created the world's first working programmable general computer 1935-41. [...] It was pointed out that none of the computers built during the 1940s were influenced in any way by Turing's 1936 theoretical paper, [...]"
Harold Abelson points out in one of his lectures [0] that computer science isn't about computers any more than biology is about microscopes.
From that perspective, it is clear that Turing found an existing discipline of computer science and made major contributions to it. But it doesn't really seem right to say that he invented or founded computer science.
[0] https://www.youtube.com/watch?v=-J_xL4IGhJA&list=PLE18841CAB...
But it's certainly not the study of what mechanical computers can do. Among other things, mechanical computers all have bounded resources unlike Turing machines.
Nobody is saying that's not important. But the field as a whole began before mechanical computers were invented or practical, and there are several subfields that are basically indistinguishable from mathematics.
In any university, Chemistry is not the study of beakers nor is astronomy the study of telescopes.
Both Software Engineering and Computer Engineering exist, as sub-disciplines, but it doesn't make sense to argue that somehow studying Graphene (a chemical which exists) is Chemistry while studying non-blocking algorithms is only Applied Computer Science somehow just because such algorithms could be used on an actual computer.
If N is sufficiently (polynomially) large, the two are approximately equal.
Yup, so do humans with paper and pencil.
Also if you ever work with the turing machine (NFA hooked up to an infinite recording tape) it is not at all "intuitive" that this construction comprehensively captures the world of computation.
Is Lisp such a mechanization?
The famous Lisp Machines of the 1980s were reasonably traditional Von Neumann computers with nice features like tagged memory and optimized stacks.
Much closer to mechanizing lambda calculus, but still a bit Von Neumannish, is the SECD virtual machine for Lisp and friends:
Turing Machines, on the other hand, were instantly obviously mechanizable. It was clear that one could build a physical machine to run any Turing program without human input. By proving that they could simulate the other systems, Turing showed that those other systems could be mechanizable as well.
I don't understand why Schmidhuber continues to ignore this crucial point.