A bit in two minds about this:

Alan Turing is a national hero. His contribution to computer science, and hence to the life of the nation and the world, is incalculable. The ripple-effect of his theories on modern life continues to grow, and may never stop.

The current Bank of England £10 notes are Series E, but Series F notes are already in circulation for some denominations. We therefore call upon the Treasury to request the Bank of England to consider depicting Alan Turing when Series F £10 banknotes are designed.

Very much in two minds.

For Turing\’s thing was for boys, adolescents at best, rather than men.

And we seem to have gone through a rather large change over the decades. Anyone with piccies of his 17 year old girlfriend\’s naked titties (it\’s fine for him to see them, paw them, nibble, bite and squeeze them, just not to have a representation of them) is at risk of going onto the sex offender\’s register. Two men who wish to swap bodily fluids are just fine now.

That latter is of course as it should be. But without going so far as to excuse Gary Glitter perhaps the former is, umm, just a tad excessive?

And Alan Turing, great man he was. Genius. But he does rather seem to get caught under either set of sexual morals, doesn\’t he? Yes, he was persecuted then for being a pooftah. He\’d be done today for paedophilia.

Or perhaps we should entirely separate achievements in one part of life from failures or evils in another? Turing on the bank note, why not? But that would mean that we have to stop obsessing about Glitter or Jonathan King on reruns of ToTP as well.

For there is one set of morals that I\’m simply not willing to accept, the excuse of genius. If, just imagine, Sir Paul McC, the greatest songwriter of modern times, were to be found guilty of kiddie fiddling then his talent would not, should not, be an excuse for that behaviour. And nor would a lack of such genius, say, a talentless no hope coder, should not get a greater punishment for such than a computer genius.

Which is to say that the fact that Turing was a computer genius, in some ways a part saviour of the nation, comes in two parts. We can celebrate that, certainly, quite possibly we should.

But if we do, sweeping his failings under the carpet at the same time then we also have to do the same for talentless beat combos as well. Judge their music as harshly as we like as music but also ignore their evils as we do so.

Turing on the tenner does indeed mean The Sun Has Got His Hat On on ToTP.

“Turing on the tenner does indeed mean The Sun Has Got His Hat On on ToTP.”Well, ok then. But not ‘Everyone’s Gone To The Moon’. No need to go that far.

The idea that anyone wants him on the tenner only because of his brilliant, abstruse work on computer science is laughable. If he’d been a happily married father of four few of us would have heard of him. If he goes on the tenner, must he be accompanied by a bodyguard of lies?

dearieme: That’s simply not true. Turing contributed a massive amount to two fields – computer science (and its parent, mathematics) and biology. As a scientist, he was the equal of Maxwell or Feynman. You would have heard of him regardless of his personal life – the sheer amount of concepts and awards named after him (before his rehabilitation) should be enough evidence for that. For the Turing Machine alone he would be feted.

dearieme>

What a load of nonsense. Turing is the father of information theory and modern computing. He is iconic in computing circles, and it’s inevitable that, although he was not well-known at the time due to his work being classified, he is now becoming as famous as his contemporaries of lesser achievements – Einstein, for example.

As for this:

“Turing’s thing was for boys, adolescents at best, rather than men.”

I’ve never seen the suggestion before in any Turing biography I’ve read. Where does the idea come from? Not that that’s the point here, of course.

On another note, given that the purpose of the images is to help secure our money against fakery, it would be extremely appropriate to put James Ellis and Clifford Cocks on a banknote – the original inventors of the public-key cryptography systems by which (almost) all electronic commerce is now secured.

Just checked the web and confirmed that Arnold Murray, the guy Turing was convicted of having relationship with, was 19. I have never heard of any evidence of Turing being promiscuous, or any other documentation of his sexual preferences, so how do you get “Turing’s thing was for boys, adolescents at best” ?

Seriously, can anyone point to something reliable on this? It is news to me that Turing’s sex life was so well documented. All I knew about was an unconsummated childhood crush and his final conviction.

Tim adds: I’ve certainly seen comments about him being interested in the boys at a choir school.

Dave – “What a load of nonsense. Turing is the father of information theory and modern computing. He is iconic in computing circles, and it’s inevitable that, although he was not well-known at the time due to his work being classified, he is now becoming as famous as his contemporaries of lesser achievements – Einstein, for example.”

Sorry but only a tiny bit of his work on German codes was ever secret. His important work was published at the time. The question is whether it was all that original. To quote Wikipedia:

In 1935, at the young age of 22, he was elected a fellow at King’s on the strength of a dissertation in which he proved the central limit theorem,[21] despite the fact that he had failed to find out that it had already been proved in 1922 by Jarl Waldemar Lindeberg.[22]In 1928, German mathematician David Hilbert had called attention to the Entscheidungsproblem (decision problem). In his momentous paper “On Computable Numbers, with an Application to the Entscheidungsproblem” (submitted on 28 May 1936 and delivered 12 November),[23] Turing reformulated Kurt Gödel’s 1931 results on the limits of proof and computation, replacing Gödel’s universal arithmetic-based formal language with what became known as Turing machines, formal and simple hypothetical devices. He proved that some such machine would be capable of performing any conceivable mathematical computation if it were representable as an algorithm. He went on to prove that there was no solution to the Entscheidungsproblem by first showing that the halting problem for Turing machines is undecidable: in general, it is not possible to decide algorithmically, whether a given Turing machine will ever halt.

While his proof was published shortly after Alonzo Church’s equivalent proof in respect of his lambda calculus, Turing was unaware of Church’s work at the time that he developed it.[24] Turing’s approach is considerably more accessible and intuitive than Church’s. It was also novel in its notion of a ‘Universal Machine’ (now known as a Universal Turing machine), with the idea that such a machine could perform the tasks of any other machine, or in other words, is provably capable of computing anything that is computable. Turing machines are to this day a central object of study in theory of computation.

So he was elected to King’s even thought some other person did the work first. His major achievement was reformulating Gödel’s work in response to another German’s work. And his big piece of work was also done by someone else first. You know, I am not seeing the Einstein thing.

However I am surprised by the accusation of an interest in teenage boys. Nothing wrong with that of course as long as they are over age. Look at Arthur C. Clarke. First I heard of it anyway.

I assume a large part of his appeal is that he is British (unlike pretty much everyone else who was important in Mathematics and Computing) and he was persecuted. Giving Gays and Computer Scientists their own secular patron saint.

Turing was a elected as a Fellow on the strength of his mathematical abilities not because of any particular paper, but I agree that claims that he was the godfather of computing are completely ill-founded. When asked what influence Turing’s On Computable Numbers paper had in the early days of computer design, his long term mentor at Cambridge, boss at Bletchley Park and head of department at Manchester, Max Newman replied: “I should say practically none at all.”

An equally informed view comes from Prof M.V. Wilkes, who was his exact contemporary as an u8ndergraduate, took a first class degree in mathematics in the same year, worked on radar inn WWII and headed the Cambridge Computer Laboratory for 40 years, and unlike TRuring, actually built working computers and much more is here http://www.dspace.cam.ac.uk/bitstream/1810/218401/1/Wilkes.mp4

” Turing is the father of information theory ”

No, that is Claude Shannon. Nothing to do with Turing.

My compsci friends would disagree on the “importance to computing” front, but maybe they’re brainwashed too.

AT liked late teenage boys, as did Oscar. Sleazy, but when translated into straight that falls in the Stringfellow bracket of “acceptably disreputable but still totally legal”.

I’ve certainly seen comments about him being interested in the boys at a choir school…Where, exactly? I’ve never heard of this, and if we’re going to damn the bloke as a paedophile or, at least, ephebophile it’s only fair to make sure the charges stick.

I really don’t care who’s on a banknote, though. It was hilarious, admittedly, to find creationist slogans scrawled over Darwin’s features one time.

So he was elected to King’s even thought some other person did the work first. His major achievement was reformulating Gödel’s work in response to another German’s work. And his big piece of work was also done by someone else first. You know, I am not seeing the Einstein thing.Then you don’t understand how important the earlier work of James Clerk Maxwell and Heinrich Hertz was to Einstein’s work on the relationship between mass and energy.

That’s how mathematics and science work – you build on earlier discoveries – and even Newton, who was about as egotistical as its was possible to get, freely admitted to having stood on the shoulders of giants.

Turing’s work stands on its own two feet as an important contribution to the development of modern computing and he deserves to be considered to be one of the fathers of the information age together with Von Neumann, Shannon and one or two others.

Tim adds: Sigh.

“and even Newton, who was about as egotistical as its was possible to get, freely admitted to having stood on the shoulders of giants.”

That was a snide remark to Hooke who was claiming that he had done a lot of work which Newton then built upon. Given that Hooke stood 4 foot 2 or something, the reference to giants should be read as Newton saying “not Hooke”.

Not fair. Hooke was a midget, but Newton still also meant the literal meaning. The point was “my excellence is based on everyone who’s done science, from cavemen onwards, except that Hooke fucker”.

What BenSix says. Source please. And it needs to go beyond him “being interested” in boys in a choir – if he was a paedophile, let’s have the evidence. I have read biographies of AT, and I haven’t seen any references to his having had any kind of relationship with a minor.

He made huge contributions both to science and to Britain’s war effort. A rare combination. I reckon that gets him on a banknote, even without any need to be politically correct.

Somebody wrote:

“fathers of the information age together with Von Neumann, Shannon and one or two others.”

One or two others? Are you kidding me? The thing about the development of computers is that it was generally a collaborative effort and even where there wasn’t direct collaboration there were several groups moving in the same direction, many preceding Turing and many others working in the field long before and long after Turing, and more importantly, unlike Turing they actually built working machines. In the UK you would have to include people like Tommy Flowers who worked largely independently of Turing when he built the Colossus machine (Turing was in the US when it was being designed and built so his contribution was minimal), Freddie Williams, Tom Kilburn and Geoff Toothill at Manchester, Wilkes, Wheeler and others at Cambridge, but they were all preceded by Antonoff and Zuse, Eckert and Mauchly who built the Univac while Turing was still scribbling his designs, the EDVAC team, the many physicist at AT&T in Murray Hill who developed semiconductors, von Neumann, Howard H. Aiken and the other the developers at IBM who built the Harvard Mark I and delivered it in 1944 while Turing was still working on cryptography at Bletchley Park, and the earlier workers at IBM and other US companies who were building electromechanical computing machines in the 1930’s. So whenever anybody tells you that Turing was pre-eminent in early computing you can tell then that is a load of tosh, largely invented by Andrew Hodges.

Minor point on classing Van Neumann up there – the Van Neumann architecture was largely invented by Turing. Given the era, it’s not surprising a lot of this work was duplicated between national groups.

“Matthew L // Jun 23, 2012 at 5:19 pm

Minor point on classing Van Neumann up there – the Van Neumann architecture was largely invented by Turing. Given the era, it’s not surprising a lot of this work was duplicated between national groups.”

Absolute crap. Absolute total tosh. The Von Neumann (you got the spelling wrong too) architecture (published in 1945) was based if anything on work by Eckert and Mauchly. The only thing that Turing had ever put down on paper was what we later called a Turing machine which was

a) a thought experiment not a physical machine,

b) never built or conceived as a practical machine but as a model for theorising about what was computable in a mathematical not a practical sense,

c) relied on potentially infinite lengths of rewritable paper tape,

d) was never “designed” in the sense of working out all the circuitry required; and

e) if it ever was built would have been hopelessly impractical and too slow to make any sense.

By the time Turing got to writing up his ideas on building a computer at the NPL in 1946/7, von Neumann had already published his papers and various groups round the world were working on building the hardware (mostly memory) needed to accomplish it.

You sir are either an idiot or a victim of homocentric revisionism, or both.

There’s no way anyone who knows as much about Turing as Alex evidently does can have concluded what he claims to have concluded without either being stupid or immensely prejudiced – so it’s most likely just trollery.

It doesn’t require “homocentric revisionism” for Turing to be overrated. I would expect computer people to prefer Turing’s super (but fictional) computer to the very primitive (but real) computers which were built around the same time. “Vision” and all that.

“It doesn’t require “homocentric revisionism” for Turing to be overrated.”

No. Homo_phobic_ revisionism is what’s required to consider Turing over-rated – and only ignorance is any other reason for considering him not under-rated.

Unity – “Then you don’t understand how important the earlier work of James Clerk Maxwell and Heinrich Hertz was to Einstein’s work on the relationship between mass and energy.”

But I do. And Einstein’s work was not exactly the same as their work but done more elegantly. Einstein massively rewrote the way we view the Universe. I mean seriously. Turing came up with a nice thought experiment. Maxwell (who I think deserves better than he gets) and Hertz did not produce Special and General Relativity just before Einstein did. They were not even close.

“Turing’s work stands on its own two feet as an important contribution to the development of modern computing and he deserves to be considered to be one of the fathers of the information age together with Von Neumann, Shannon and one or two others.”

Sure. An important contribution. One among many. Ground breaking in its way but not a massive paradigm shift. Had Turing bit the apple a little earlier, not much would have changed. Had Einstein been run over by a Swiss tram, science would be very different.

“That was a snide remark to Hooke who was claiming that he had done a lot of work which Newton then built upon. Given that Hooke stood 4 foot 2 or something, the reference to giants should be read as Newton saying “not Hooke”.”

Hmmm. I am not convinced. The phrase is an old one. It was old even by the time Newton used it. I doubt that he was having a go at Hooke myself. More a standard cliche.

Dave – “No. Homo_phobic_ revisionism is what’s required to consider Turing over-rated – and only ignorance is any other reason for considering him not under-rated.”

Yeah but that is because everyone denied Ada, Countess Lovelace all the credit hates women. Typical of Britain’s bitchy Gay community. Come on. This is tiresome. We can look at what Turing did. Lovely thought experiment. In the tradition of British mathematical logic. Useful. Just not vital or paradigm-changing. The comparison with Einstein is ridiculous. If you wanted to go back in time and delay the invention of the computer, Von Neumann would be the person to whack. Not Turing. Although that may have wider ramifications on the modern world than you would want.

Turing has the sort of story liberal arts graduates who write histories like. That does not mean he has the sort of impact they would claim. Homophobic or not.

Comparing Turing to Einstein is a joke. Without his conviction for certain acts, and his subsequent suicide, it is unlikely we would have heard of him. He would be known only to a very small number of computation academics.

Turing is a saint / martyr not only for computer scientists and homosexuals, but also for the autistic and aspergers syndrome community. Still not sure that makes him worthy of inclusion on a banknote. It’s too soon to tell whether his fame will stand the test of time.

I don’t believe Turing was a paedophile: if Tim’s got any actual evidence for this, let’s hear it.

I’ve no objection to seeing Turing on a banknote. But the scientist I’d really like to see given this recognition is James Clerk Maxwell: both for his prediction of electromagnetic radiation and for his cracking beard.

And it is claimed today that Turing may not even have topped himself. Nor MI-5 . Which is a blow. I always liked that theory for its sheer lunacy. They are claiming an accident in the lab.

http://www.dailymail.co.uk/news/article-2163628/Alan-Turing-Enigma-codebreaker-died-accident-NOT-suicide-claims-expert.html

I did like this from the coroner:

‘In a man of his type, one never knows what his mental processes are going to do next.’

Well, quite so. Although whether that is due to his homosexuality, autism (allegedly) or being Computer scientists or a Don is undetermined.

A ten quid note is not worth much and getting less by the day.

‘course, if we’re gonna consider current sexual/moral laws/attitudes retrospectively, we’ll need to consider the case against the Duke of Edinburgh.

Her Madge was 13 when he started writing to her, and he, five years older was an “adult” of 18.

These days he’d be done for grooming.

On the other hand, Brunel is absurdly over-rated too. On the third hand, there is that wonderful photo of him with the chains and cigar.

Dave said:

“No. Homo_phobic_ revisionism is what’s required to consider Turing over-rated – and only ignorance is any other reason for considering him not under-rated.”

Or an objective view of the facts. Turing’s paper On Computable Numbers came 5 years after Godel published his solution to the Entscheidungsproblem, so Turing’s work added nothing new to pure mathematics, nor did he claim that it would, and there were problems getting it published. The interesting part about Turings paper was for its model of computation, but the system that he developed was equivalent to Alonso Church’s earlier lambda calculus, Emil Posts’s roughly contemporaneous computational models or Stephen Kleene’s slightly later General Recursive Functions. Turing’s theoretical machine has some appeal because it resembles a paper tape machine connected to a box of electronics, but I prefer Kleene’s model because it is easier to represent in today’s high level languages, but there you go. So marks out of 10: probably an 8 for Turing because it was only his model not his mathematics that was original.

At Bletchley Park Turing ran one of the huts, but contrary to the myths peddled by many of his supporters, he wasn’t the first to break the Enigma code. That was done by 3 Polish cryptographers who also built the first bombe. they handed their work over to the British when they knew they couldn’t take it any further. Nor was Turing the first to break the Enigma at Bletchley Park. That was Dilly Knox a Classics don from Cambridge. Turing’s contribution was to enhance the performance of the Enigma by applying statistical analysis to the operation of the bombes, vastly improving their performance. But he wasn’t the only person to improve the performance of the bombes. Gordon Welchman took over the development when Turing went to America and made further improvements. But two other great achievements at Bletchley Park which arguably were greater technical achievements were the cracking of the Lorenz cipher by Bill Tutte (without the benefit of an encrypting machine as was the case for the Enigma) and the construction of the Colossus machines by Tommy Flowers and the GPO, neither of which involved Turing (not that the Turing fan boys would like you to realise). Still: Marks out of 10 for Turing: 8.5, Good but he was not acting alone.

Then we come to the construction of early computers. Of all the computers produced between Turing’s paper On Computable nNumbers and his death (i.e. Zuse Z3, Atanasoff–Berry Computer, Colossus Mark 1, Harvard Mark I – IBM ASCC, Colossus Mark 2, Zuse Z4, ENIAC, Manchester SSEM, ENIAC, EDSAC, Manchester Mark 1, CSIRAC, Unicac, Ferranti Mark I, IBM 650), how many did he develop? Answer: none. It follows that is ridiculous to give Turing credit for work that was actually done by others, particularly as Max Newman explained, Turing’s paper in the 1930’s had practically no influence on early computer developers. Despite this, did Turing get involved with nuts and bolts of early computers, writing operating systems and high level languages? Did he hell. Score out of 10: 0.

Why was Turing widely ignored after WWII? First of all because building computers required electronics expertise which he didn’t have. Secondly, because Turing wasn’t a project manager. I had the privilege of studying CompSci at Cambridge in the 1970’s where I not only heard the views of Wilkes on Turing, but also discussed Turing with Prof Harry Hinsley at dinner (the official biographer of MI6 who also worked at Bletchley). I also had a maths teacher at school who worked in Turing’s hut at BP and they all said the same thing. He couldn’t manage people, projects or budgets and usually refused to speak to anyone except his immediate subordinates. That made it very easy for the government to decide to put other people in charge of projects.

People who worked in early computers do not understand the modern, mostly liberal arts led fascination with Turing, whose work in Computation Theory had little influence on theirs.

He’d be done today for paedophilia.Right. You’ve been asked several times already.

Have you got any evidence for this, or not?

To say Alan Turing was the father of modern computing was always a bit of a stretch. Certainly his theoretical models demonstrate some of the principles required, but the same could be said of many others from Ada Lovelace onwards.

Perhaps the reason why he is considered such is purely the coincidence that his residence as a code breaker at Bletchley Park coincided with the creation of the first electronic computer there, although this was largely the effort of Tommy Flowers and based upon a vast amount of prior-technology with the GPO which was used for switching and directing telephone traffic.

Much of the foundational work leading up to the construction of the Colossus computer at Bletchley Park was based upon prior work at the Post Office Research Station established in 1925, so at best they could be described as “standing on the shoulders of others”.

World War II and the requirement for automation of de-cyphering techniques was the driver towards modern computing rather than anything else and the earliest examples of this come from the Poles rather than the British.

It was the Poles who did all of the early running on automated de-cyphering, which was cut short by the invasion of Germany in 1939.

Much of the equipment invented by the Poles was transferred / reconstructed at Bletchley Park and these machines were the pre-predecessors’ to Colossus rather than the theoretical work done by Alan Turing.

http://en.wikipedia.org/wiki/Bomba_(cryptography)

Numbers came 5 years after Godel published his solution to the EntscheidungsproblemBzzzt.

The Entscheidingsproblem concerns algorithmic decidability. Goedel’s theorems are about completeness/consistency.

so Turing’s work added nothing new to pure mathematicsSo he didn’t solve the halting problem then? He didn’t establish the existence of incomputable real numbers? No? Fascinating.

The interesting part about Turings paper was for its model of computationWell that’s one way of putting it. For the first time, the notion of mathematical algorithm was equated with a

mechanical process.Is that an important moment in the history of science? (Even as a thought experiment, granting that Turing machines were never intended as practical designs?)

The correct asnwer is: hell yes.

And then he took it a step further, by establishing the possibility of a Universal Turing Machine – one that can carry out any algorithm that any other machine.

This purely theoretical discovery was a rigorous proof of concept of the stored-program computer. 8/10, my arse.

but the system that he developed was equivalent to Alonso Church’s earlier lambda calculusYup. And who proved that equivalence? Oh, it was Alan Turing, wasn’t it? And his proof of this important result led to (yes, with the input of others along the way) the Church-Turing thesis, one of – or perhaps the single – most important guiding principles in computer science.

The question I have is: why is thread full of people attempting to downplay a great scientist’s achievements, when they obviously have inadequate knowledge about the subject?

dearieme – “On the other hand, Brunel is absurdly over-rated too. On the third hand, there is that wonderful photo of him with the chains and cigar.”

Not for long there isn’t. Another ten years and there will only be photos of him with the chains.

The question I have is: why is thread full of people attempting to downplay a great scientist’s achievements, when they obviously have inadequate knowledge about the subject?Perhaps because we give greater weight to those who prove the practicality of a machine by building it than those who put forward the theoretical basis for its operation.

One reason might be that mathematics and theoretical physics is the province of the lone individual, whereas the skills required for engineering a working machine are more geared towards team efforts, even Tommy Flowers was only the lead engineer of a team.

“The question I have is: why is thread full of people attempting to downplay a great scientist’s achievements, when they obviously have inadequate knowledge about the subject?”

The question I have is why all the Turing supporters are making unrealistic claims about his pre-eminence and to the discredit of many of his contemporaries who actually did achieve something.

It is all very well talking about ideas and plans which may or may not have worked, but the fact is that other people not only designed computers, but built them and made them work,, using their own designs, not Turing’s. Still, we shouldn’t single out the Turing fanboys. There is a group from the NPL who think they invented packet switching (albeit several years after the Americans).

So you’re filing the the Universal Turing Machine under

“ideas and plans which may or may not have worked”?Wow.

Larry wrote “So you’re filing the the Universal Turing Machine under “ideas and plans which may or may not have worked”?”

No, but it is largely irrelevant to computer designers. All modern computers are Turing equivalent or complete or whatever you want to call it, but that doesn’t mean computer designers really worry about it, any more than IBM are greatly indebted to the first caveman who discovered/invented a blue pigment.

“No. Homo_phobic_ revisionism is what’s required to consider Turing over-rated – and only ignorance is any other reason for considering him not under-rated.”

You should really take into account how different people are impressed by different things.

Even if Turing invented the computer single-handedly (which he didn’t), I would rate this achievement well below Einstein, and somewhere about the same as those guys who invented the transistor.

Possibly because I am interested in physics and chemistry, and not at all interested in computers or pure mathematics, which is hardly a sign of homophobia.

As both Friend of Dorothy and the International Faggots conspiracy (I’m forced to wear leather boots during Gay Pride), I find Alan Turing’s qualifications as a gay icon or even a gay martyr somewhat under-whelming.

Don’t get me wrong, he was subjected to shitty treatment for committing a sexual act with a consenting adult in his own home. How many gay men of the time got banged up for years for either sodomy or gross-indecency?

Equally, was his 1936 paper that critical? Certainly it describes the theoretical operation of a general purpose electronic computer based upon logical and arithmetic operation, but although prescient, was it that fundamental?

I would argue that Babbage’s difference engine had most of these characteristics and although only partially complete was a great leap forwards (especially since it was partially built and demonstrable) 100 years before Turing put pen to paper.

In comparison to Einstein, whose two greatest papers were of immediate practical use to astronomers trying to understand the universe, Turin’s theoretical machine had no practical application until people like Tommy Flowers with Colossus or US ABRL with ENIAC decided to put the theory into practice.

I’ve yet to come upon an infinite role of paper tape on Ebay.Equally, was his 1936 paper that critical?Well, that really depends who you ask.

If you ask someone with a some understanding of theoretical computer science, they’ll tell you that it was a real watershed moment, because it established for the first time, and with mathematical rigour, the theoretical possibility of a mechanical device capable of universal computation. And he explained what “universal computation” (or “Turing completeness”) really meant, which would be the goal for all subsequent computer-builders to aim for. (For the record, Babbage’s difference engine was *not* Turing complete. His subsequent analytical engine, which was never built, would have been. But of course he didn’t understand the issues involved here because – guess what – Turing hadn’t yet come along to explain them.)

On the other hand, if you ask a tiresome contrarian troll, he’ll tell you that its of equal irrelevance to a caveman squishing some rocks to make a rudimentary dye.

“Certainly it describes the theoretical operation of a general purpose electronic computer based upon logical and arithmetic operation, but although prescient, was it that fundamental?”

I wouldn’t even go that far. Turing’s paper described a finite state machine (a well-known concept to the mathematicians at the Institute for Advanced Studies at Princeton) with an attached potentially infinite memory, but he didn’t actually specify it as electronic or in any way different to the electro mechanical tabul;ating machines produced by IBM and NCR, no circuits or other designs. And although he proved that a simple design for the finie stae machine could with enough tape to specify the problem and enough time to run it solve any of the programs that are solved by modern computers, albeit that with a Turing machine would require vast amounts of tape and until the end of the universe to solve problems that computers would solve in a few minutes, hours or days. The point of the Turing machine was not to act as a blueprint for future computers but to demonstrate first of all that aa machine as relatively simple as a Turing machine could perform all of the computations that could be performed by more powerful machines and secondly that by building a Turing machine that operated on the schematic representations of Turing machines which were recorded on tape (Universal Turing Machines), Turing showed that there were problems that could be specified but not solved by a Universal Turing Machine.

Which was nice, but of no use whatsoever to the creators of the first computers who were just trying to add up a few numbers and calculate a few primes before their valves went on the fritz.

“On the other hand, if you ask a tiresome contrarian troll, he’ll tell you that its of equal irrelevance to a caveman squishing some rocks to make a rudimentary dye.”

Then Larry, I suggest you watch this video of Professor Wilkes, who was one of the first builders of computers (I suspect you were not) and listen to his views of the relevance of Turing’s work.

http://www.dspace.cam.ac.uk/bitstream/1810/218401/1/Wilkes.mp4

The fact is that Turing showed that a universal basis for computing requires remarkably few primitives, but the first computer engineers realised that Turing’s simple machine was no basis for real computers and that Turing’s designs were hopelessly impractical. In the 76 years since Turing’s paper nobody has built a serious machine that used a sequential memory to store the immediate results of calculations like Turing’s machine, nor was their operation decided by a machine state. Real machines ever since the time of von Neumann used registers, status bits, program counters and addressable memory noneof which featured in Turing’s machine but which have been fairly standard in all computers since the mid 1940s.

I listened the Wilkes speech (precis here: http://blog.oup.com/2012/06/maurice-wilkes-on-alan-turing/ )

He denies the existence of theoretical computer science as a valid subject at all, and says that all such results should be treated as pure mathematics. (In which context he agrees that Turing’s work was “a great contribution to the world of mathematics”.)

Fair enough. That’s a rather unusual view (and I dare say it became even more unusual when he died in 2010). But he’s certainly earned the right to speak his mind.

In contrast, this is what von Neumann thought about Turing’s work:

I know that in or about 1943 or ’44 von Neumann was well aware of the fundamental importance of Turing’s paper of 1936 … Von Neumann introduced me to that paper and at his urging I studied it with care. Many people have acclaimed von Neumann as the “father of the computer” (in a modern sense of the term) but I am sure that he would never have made that mistake himself. He might well be called the midwife, perhaps, buthe firmly emphasized to me, and to others I am sure, that the fundamental conception is owing to Turing– in so far as not anticipated by BabbageThose are the words of Stanley Frankel, a colleague of von Neumann’s who programmed the ENIAC. (Source.)

There seems to be some misunderstanding here. The Turing Machine isn’t supposed to be a design for a working computer: it’s a concept which makes accessible the problem of computability. Turing’s major contribution to the design of actual computers was his 1946 paper on ACE.

This is a good account of Turing machines, and the difference between theoretical computer science and designing a physical machine:

http://scientopia.org/blogs/goodmath/2012/06/24/turing-machines-what-they-are-what-they-arent/

Scrabbler>

“Possibly because I am interested in physics and chemistry, and not at all interested in computers or pure mathematics, which is hardly a sign of homophobia.”

Not at all, merely of not knowing much about Turing – which is no big deal, since you’re not particularly interested in it.

Turing on the tenner – meh. Put Eric Gill on the £20.

Cat, pigeons, &c.

Dave, I don’t agree that not caring about computers means one does not know much about Turing. However, the conclusion that Turing is significantly underrated rests on the very subjective assumption that early theoretical work relating to computers is a very big deal.

“that the fundamental conception is owing to Turing – in so far as not anticipated by Babbage”

Not really very high praise, considering how little people seem to care about Babbage.