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Deutsch Misquoted Turing

David Deutsch (DD) wrote in Quantum theory, the Church-Turing principle and the universal quantum computer (1985), p. 3:

Church (1936) and Turing (1936) conjectured ... This is called the ‘Church-Turing hypothesis’; according to Turing,

Every ‘function which would naturally be regarded as computable’ can be computed by the universal Turing machine. (1.1)

And from Deutsch's references (p. 19):

Turing, A. M. 1936 Proc. Lond. math. Soc. Ser. 2, 442, 230.

Now we'll compare with Turing's paper: On Computable Numbers, With An Application To The Entscheidungsproblem (1936), p. 230:

the computable numbers include all numbers which could naturally be regarded as computable.

Turing wrote "numbers", but DD misquoted that as "function". Turing also wrote "could" which DD misquoted as "would".

I double checked using two other copies of Turing's paper. (One and two.)

There's also a problem because Deutsch uses what appears to be an italicized block quote. You'd expect the whole block quote to be a quote of Turing, but instead it's a paraphrase. Inside the paraphrase are quotation marks surrounding the misquote of Turing that I criticized.

DD's citation is also incorrect. DD cites Turing's paper to volume 442 of the Proceedings of the London Mathematical Society, but it was actually in volume 42 not 442.

To determine what's correct, we can check how Turing himself cites it. In a correction to his paper, Turing cited himself:

Proc. London Math. Soc. (2), 42 (1936-7), 230-265.

You can also get the correct cite, with volume 42, from the Stanford Encyclopedia of Philosophy or from Wikipedia.

You can also see that the latest volume of the journal, published in 2021, is volume 122. Volume 442 is unlikely to exist for over 100 more years. And the journal's website has archives showing that the Turing article was in volume 42.

Tangentially, I hope this lowers your opinion of academic peer review. DD's paper was published in Proceedings of the Royal Society of London, a prestigious and peer-reviewed journal that started in around 1830. It has published work from many famous scientists.

Thanks to Dec for finding this misquote.

Note that DD has published a lot of misquotes.

Update 2021-07-15: Dec pointed out that a similar Turing misquote is in DD's book The Fabric of Reality:

He [Turing] conjectured that this repertoire consisted precisely of ‘every function that would naturally be regarded as computable’.

No, Turing wrote "all numbers which could" not "every function that would".

It appears that DD got this misquote from his own paper, and also modified it. There's a recurring pattern where every time DD touches a quote, there's a significant chance that he changes something. Here, he took the word "every" which was outside of quote marks in his paper and moved it inside quote marks for his book.

Elliot Temple on July 12, 2021

Messages (12)

The volume number being off by 400 violates expectations for people familiar with the context who know what sort of numbers to expect and who actually read that journal. DD wrote a number that won't exist for a long time if ever.

It's like if you cite page 4,050, that should stand out as a possible error to a reviewer familiar with books. How many books have 4000+ pages? It'd have to be like a 10 volume set that carried over page numbers between volumes, or maybe some recent ebook is that long. If the cite didn't mention e.g. volume 8, that'd be an additional clue.

You'd expect peer reviewers to be familiar with the context of what journal volume numbers are reasonable and to be able to catch an error like this. They should be used to e.g. many journals doing one volume per year or a similar amount, and no journals being 400+ years old. (The oldest journal appears to be 356 years old in 2021 and to have reached volume 376.) But apparently peer reviewers don't know stuff like that or don't pay attention or something?

I caught the cite error despite lacking familiarity with stuff like journal volume numbering conventions. A peer reviewer should have been in a better position than me to catch it.

Do peer reviewers not bother to fact check citations? Do they just skip reviewing some parts of what's being published? But they want us to trust stuff because it's peer reviewed?

curi at 1:20 PM on July 12, 2021 | #1 | reply | quote


> **Reviewing instructions**

> Attention should be paid to:

> References — these should be appropriate, relevant, and devoid of unnecessary self-citations.

That doesn't specifically say to check the references for accuracy. Maybe they take it for granted that the authors will quote and cite accurately? Or takes for granted that reviewers know to check for that? Or they don't care? They ought to instruct reviewers to check.

> If you have any suspicion of misconduct please alert the Editorial Office as soon as possible. This can include fabrication of results, plagiarism, duplicate publication, incorrect authorship or any other area of concern.

OK. I think publishing false quotes is a type of misconduct, so I emailed them as they requested.

curi at 1:42 PM on July 12, 2021 | #2 | reply | quote


> To be acceptable for publication a paper should represent a significant advance in its field, rather than something incremental.


> Manuscripts that lack novelty or only present an incremental advance over previous work are not acceptable.

That anti-incremental-progress attitude is bad.

curi at 1:44 PM on July 12, 2021 | #3 | reply | quote

> DD's paper was published in *Proceedings of the Royal Society of London*

The head editor of that journal, today, is DD's friend, Michael Lockwood (ML). I don't know when he became head editor. I searched briefly and didn't find a timeline for previous people in that job.

ML is a fellow of the royal society, like DD.

It strikes me as pretty incestuous.

ML's son is Nick Lockwood (NL).

NL used to post a bunch on TCS list.

NL hung out with both DD and SFC in person a lot. SFC talked about driving him around the UK countryside and showing him castles. Now his father, ML, is head editor of the prestigious journal that publishes DD's misquotes, and is in the same prestigious organization that DD got into.


> His findings are key for climate change studies.

I don't know if ML is really a climate change "scientist" (presumably a political propagandist) or the royal society just thought that was the best way to advertise his real, productive work.

ML was elected to the royal society in 2006. DD was elected in 2008.

It all looks like a bunch of social climbing with social networks, personal friends, personal favors, etc.

DD's royal society bio says:


> In 1985, he wrote a pioneering paper that proposed the idea of a universal quantum computer, and then made some of the most important advances in the field, including his discovery of the first quantum algorithms.

That "pioneering paper" they're bragging about, which they themselves published, is the shoddy paper where he misquotes Turing.

Anonymous at 6:17 PM on July 12, 2021 | #4 | reply | quote

#4 Based on a quick search, Nick Lockwood wrote around 300 TCS emails from his main email. He's now blocking me on Twitter. I don't know when or why.

We never talked a lot. His involvement in TCS was more before I joined.

Later, he publicly called the TCS community an "idealist, right wing echo chamber that is hostile to criticism". He did not attempt to offer any serious critical arguments that I recall. He did not identify any criticism he thought had received a hostile response. He did not try to objectively document his claims.

He said he left TCS, philosophy and reason because he "developed other interests". Contrary to that statement, he then claimed that actually he's involved with philosophy. But he neglected to mention anything substantive that he's doing philosophically, he doesn't appear to blog or otherwise about philosophy, and he didn't mention any superior, alternative discussion places that he'd found.

curi at 6:35 PM on July 12, 2021 | #5 | reply | quote


Here’s an instance of Deutsch’s paraphrase being confused with an actual Turing quote. This is from a Stanford University quantum computer science course:

> *Every “function which would **naturally** be regarded as computable” can be computed by the universal Turing machine. – Turing*

https://cs269q.stanford.edu/lectures/lecture1.pdf (p. 28)

They haven’t even cited Deutsch as the source. Here it looks like Turing is quoting someone and that he named the universal machine after himself. They’ve bolded “**naturally**” for some reason. All very misleading. Such bad scholarship in a prestigious comp sci course.

Dec at 6:44 PM on July 12, 2021 | #6 | reply | quote

#6 Awful. They clearly copied it from a secondary source (DD) without checking the primary source, and without attributing it to where they got it. And they present it like the whole thing is a Turing quote that contains internal quotation makes. Did they even notice the internal quotation marks? How can they see something odd like that and see no need to check the original to find out what's going on? Uncurious and incompetent both? Focused only on social climbing, not thinking?

Anonymous at 6:51 PM on July 12, 2021 | #7 | reply | quote


When I see misquotes like the one in Deutsch’s paper that haven’t been noticed for decades, I wonder what else doesn’t stand up. Like has anyone actually checked the maths really carefully?

Dec at 8:53 PM on July 12, 2021 | #8 | reply | quote

#8 Maybe one or two people tried to do that. Who knows if they were good at what they were doing. Even if good, they could have missed something.

I was just talking with a friend about it before seeing your comment. I don't know if the math or physics in DD's old work is good. I don't know for other physicists either. Some people clearly got some things right somewhere (hence radios, GPS, nuclear power plants, some other stuff that *works*).

It's hard to check partly because I don't know enough math and physics. And partly because the information is communicated poorly and in a way that's hostile to outsiders and self-educated people. Which is ironic given that DD told everyone to homeschool.

They use lots of jargon, symbols and conventions without citing any source that explains or documents them all. Some are hard to look up, e.g. because you don't know the name of a symbol or it's a standard symbol but you don't know the special name for using it in that kind of formula. Also conventions change over time and the lack of documentation of what some stuff means adds not only barrier to entry but also makes the papers less timeless. It can be a big problem for expert mathematicians and physicists reading it many years later. I think it can be an issue on a timescale of decades, and also the issue is worse between different countries, and it's even worse if you're thinking about e.g. a mathematical historian trying to read this stuff 5000 years from now.

It's hard to get people to answer a large number of questions they regard as basic, and to consistently get answers. There are forums (like on reddit or stackexchange) that probably get annoyed if you ask too much and only answer half your questions because no one takes responsibility for answering stuff. So you get some answers but it's incomplete. And getting personal attention from anyone who actually cares to keep answering until everything is clear is ... hard. Alan Forrester will answer some stuff. Without him it'd be a lot harder.

Anonymous at 8:59 PM on July 12, 2021 | #9 | reply | quote


> Michael [Lockwood] is also distinguished for his use of spacecraft to investigate the flow of particles from one part of the atmosphere into another — the ionosphere (the upper part that can be ionised by the Sun) into the magnetosphere (the Earth’s magnetic field). His work allows the prediction of atmospheric behaviour.

They make it sound like he used spacecraft because he’s smart.

That is not what’s going on. Many people would like to use spacecraft. He got funding and assistants.

Did he get those by being the smartest scientist who could make the best use of spacecraft, budget the money in the best way, organize a team in the best way, etc? (Note btw that there are non-scientific skills involved there which are outside the specialization of someone who actually focuses their attention on science.) How do the funders decide? Here are two hints from the same bio about what funders look for:

> He has openly criticised those in the scientific field who do not see the need for human action against climate change. He has published several hundred papers

Most people don’t write several hundred papers themselves. He’s probably getting a lot of credit for work he got graduate students and other types of assistants to do. That’s generally more about social climbing in a “publish or perish” funding landscape than about productive work.

And scientists who get involved in current political controversies, and who specifically pile on to criticize dissent/disobedience regarding proposed government actions, are mostly social climbers.

A lot of the funding comes from the government, and goes to whoever can pose as a scientist – who can put on a show and get a scientific reputation – while helping enable government power and control.

Anonymous at 11:29 AM on July 13, 2021 | #10 | reply | quote


There are two UK intellectuals, both connected with Oxford, named "Michael Lockwood". DD's friend, who is cited in both of DD's books, appears *not* to be the royal society guy, though I don't know how to look it up properly because they're both referred to by the identical name.


Anonymous at 2:44 PM on July 13, 2021 | #11 | reply | quote

Updated the post b/c DD put the same Turing misquote – but modified with an additional error – in FoR.

curi at 10:45 AM on July 15, 2021 | #12 | reply | quote

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