Category: Book Reviews

Reviews of books featuring a summary of the book and links to related material

Oct 14 2012

Book Review: Alan Turing: The Enigma by Andrew Hodges

2012editionA brief panic over running out of things to read led me to poll my twitter followers for suggestions, Andrew Hodges’ biography of Alan Turing, Alan Turing: The Enigma  was one result of that poll. Turing is most famous for his cryptanalysis work at Bletchley Park during the Second World War. He was born 23rd June 1912, so this is his 100th anniversary year. He was the child of families in the Indian Civil Service, with a baronetcy in another branch of the family.

The attitude of his public school, Sherbourne, was very much classics first, this attitude seems to have been common and perhaps persists today. Turing was something of an erratic student, outstanding in the things that interested him (although not necessarily at all tidy) and very poor in those things that did not interest him.

After Sherbourne he went to King’s College, Cambridge University on a scholarship for which he had made several attempts (one for my old college, Pembroke). The value of the scholarship, £80 per annum, is quite striking: it is double the value of unemployment benefit and half that of a skilled worker. He started study in 1931, on the mathematics Tripos. His scholarship examination performance was not outstanding. Significant at this time is the death of his close school friend, Christopher Morcom in 1930.

King’s is a notorious hotbed of radicals, and at this time Communism was somewhat in vogue, a likely stimulus for this was the Great Depression: capitalism was seen to be failing and Communism offered, at the time, an attractive alternative. Turing does not appear to have been particularly politically active though.

During his undergraduate degree, in 1933, he provided a proof of the Central Limit Theorem – it turns out a proof had already been made but this was his first significant work. He then went on to answer Hilbert’s Entscheidungsproblem (German for “Decision Problem) in mathematics with his paper, “On computable numbers”1. This is the work in which he introduced the idea of a universal machine that could read symbols from a tape, adjust its internal state on the basis of those symbols and write symbols on the tape. The revelation for me in this work was that mathematicians of Turing’s era were considering numbers and the operations on numbers to have equivalent status. It opens the floodgates for a digital computer of the modern design: data and instructions that act on data are simply bits in memory there is nothing special about either of them. In the period towards the Second World War a variety of specialised electromechanical computing devices were built, analogue hardware which attacked just one problem. Turing’s universal machine, whilst proving that it could not solve every problem, highlighted the fact that an awful lot of problems could be solved with a general computing machine – to switch to a different problem, simply change the program.

Alonzo Church, at Princeton University, produced an answer for the Entscheidungsproblem  at the same time; Turing went to Princeton to study for his doctorate with Church as his supervisor.

Turing had been involved in a minor way in codebreaking before the outbreak of World War II and he was assigned to Bletchley Park immediately war started. His work on the “Turing machine” provides a clear background for attacking German codes based on the Enigma machine. This is not the place to relate in detail the work at Bletchley: Turing’s part in it was as something of a mathematical guru but also someone interested in producing practical solutions to problems. The triumph of Bletchley was not the breaking of individual messages but the systematic breaking of German systems of communication. Frequently, it was the breaking of a system which was critical in principle the Enigma machine (or variants of it) could offer practically unbreakable codes but in practice the way it was used offered a way in. Towards the end of the war Turing was no longer needed at Bletchley and he moved to a neighbouring establishment, Hanslope Park where he built a speech encrypting system, Delilah with Don Bayley – again a very practical activity.

Following the war Turing was seconded to the National Physical Laboratory where it was intended he would help build ACE (a general purpose computer), however this was not to be – in contrast to work during the war building ACE was a slow frustrating process and ultimately he left for Manchester University who were building their own computer. Again Turing shows a high degree of practicality: he worked out that an alcohol water mixture close to the composition of gin would be almost as good as mercury for delay line memory*. Philosophically Turing’s vision for ACE was different from the American vision for electronic computing led by Von Neumann: Turing sought the simplest possible computing machinery, relying on programming to carry out complex tasks – the American vision tended towards more complex hardware. Turing was thinking about software, a frustrating process in the absence of any but the most limited working hardware and also thinking more broadly about machine intelligence.

It was after the war that Turing also became interested in morphogenesis2 – how complex forms emerge from undifferentiated blobs in the natural world, based on the kinetics of chemical reactions. He used the early Manchester computer to carry out simulations in this area. This work harks back to some practical calculations on chemical kinetics which he did before going to university.

Turing’s suicide comes rather abruptly towards the end of the book. Turing had been convicted of indecency in 1952, and had undergone hormone therapy as an alternative to prison to “correct” his homosexuality. This treatment had ended a year before his suicide in 1954. By this time the UK government had tacitly moved to a position where no homosexual could work in sensitive government areas such as GCHQ. However, there is no direct evidence that this was putting pressure on Turing personally. Reading the book there is no sick feeling of inevitability as Turing approaches the end you know he has.

Currently there are calls for Turing to be formally pardoned for his 1952 indecency conviction, personally I’m ambivalent about this – a personal pardon for Turing is irrelevant: legal sanctions against homosexual men, in particular, were widespread at the time. An individual pardon for Turing seems to say, “all those other convictions were fine, but Turing did great things so should be pardoned”. Arnold Murray, the man with whom Turing was convicted was nineteen at the time, an age at which their activities were illegal in the UK until 2000.

What struck me most about Turing from this book was his willingness to engage with practical, engineering solutions to the results his mathematical studies produced.

Hodges’ book is excellent: it’s thorough, demonstrates deep knowledge of the areas in which Turing worked and draws on personal interviews with many of the people Turing worked with.

Footnotes

1. “On computable numbers, with an application to the Entscheidungsproblem”, A.M. Turing, Proceedings of the London Mathematical Society 42:230-265 (1936).

2. “The Chemical Basis of Morphogenesis”, A.M. Turing, Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, Vol. 237, No. 641. (Aug. 14, 1952), pp. 37-72.

3. My Evernotes for the book

4. Andrew Hodges’ website to accompany the book (link)

Jul 25 2012

Book review: A computer called LEO by Georgina Ferry

AComputerCalledLEOThis is a review of “A Computer called LEO” by Georgina Ferry, recounting the story of the first computer developed for business use by J. Lyons & Co, the teashop and catering company.

Lyons formed in 1884, a spin-off from a family tobacconist company whose traveling salesman realised that there were few reliable teashops around the country, furthermore catering at large events such as the Great Exhibition was poor. Over the next 30 years or so the business grew, with a chain of teashops, and smarter establishments such as the Corner Houses and Trocadero. The teashops were supplied by Lyons own manufacturing and delivery service.

By the 1930s Lyons had approximately 30,000 workers, as such it was one of Britain’s larger employers. 300 clerks were used to tot up daily takings on mechanical calculators. Clerical work had risen in important during the second half of the 19th century with numbers rising from 70,000 in Britain in 1851 to 2 million in 1901. The company had a department of Systems Research led by a Cambridge mathematician, John Simmons, who the company had recruited in 1923, the hiring of such a graduate was a novelty at the time. The Systems Research department was interested in the efficient running of the business.

By this time various items of office machinery were commonplace, things such as filing cabinets, typewriters, mechanical calculators, and punch card readers. Telephone exchanges were in place, the electronic valve had been invented in the early years of the 20th century and magnetic storage devices were starting to become available. By the 1930s people such Oliver Standingford in Lyon’s Stock Department were talking about machines which would combine these elements, although he was not clear on the detail of how this would be done.

The Second World War then intervened, Lyons cut table service from its teashops as labour went short. Various people gained useful experience in electrical engineering through the wartime developments in radar, and possibly codebreaking. We now know that Colossus, a computer used for code breaking, was built at Bletchley Park during the war but it did not become public knowledge until 1974. In the US ENIAC had been developed at the Moore School in Philadelphia to do artillery range calculations. This was not a secret and immediately after the war, Oliver Standingford and Raymond Thompson visited from Lyons; they had a broad brief to investigate American business methods but it was ENIAC which really captivated them. Fortunately, their US trip put them in touch with more local expertise in the form of Douglas Hartree at Cambridge University who was building a computer, EDSAC, for the Mathematical Laboratory.

Lyons decided fairly quickly to construct their own computer, which was to be based on the EDSAC machine; US machines such as they were could not be purchased because of currency restrictions and there were no computer manufacturers in the UK. From the start LEO I (the first computer) was different, Simmons saw the computer fitting into a system of “scientific management” and as such LEO was crafted to exactly fit the role he foresaw for it based on detailed knowledge of the company’s processes. In some senses computing for business was more demanding than the computation done in the Mathematical Laboratory and other scientific laboratories: business computing had large demands for input and output (imagine a payroll system – it needs to read in details of each employee and print out the results), it had lower tolerance for failure (payroll failing to run has a serious impact on employees) and calculations could be more “complex” than mathematical ones in the sense that more steps in calculation and more conditionality was required. It was at Lyons that the art of flowcharting was developed. The first live duty that LEO carried out was in 1951, it was made public in 1955. It’s interesting to note that Charles Babbage had highlighted the potential for automation in both manufacturing and mathematical operations in his book “On the Economy of Machinery and Manufacturers”, published in 1832.

There were to be two further LEO computers, developed by a separate company, Leo Computers Ltd however things did not go well. The computers themselves were technically advanced, and the Leo Computers method of going into a business and closely examining their processes before writing programs and delivering a system combining both hardware and software usually had excellent results. However, this had the unfortunate side-effect of losing their best staff to their clients. Other problems were afoot: Leo Computers Ltd although nominally a separate company was under-resourced both financially and in personnel with development engineers also acting as salesman. The parent company, Lyons was struggling – victim of a family business mentality which put increasingly useless family members at the heads of divisions.

In 1964 Leo Computers Ltd was merged with English Electric, with Lyons divesting itself of any responsibility, following this union the LEO line died although the final computers in the series were installed by the Post Office, and continued to run there, in places, until 1981.

In contrast in the 1960s IBM were able to make an investment of $5billion on their System 360 computers – a compatible range designed to fit every need. They had a ready market in the US both of businesses willing to buy, unlike their British counterparts, and a government who bought locally first. Faced with this opposition, the British computer industry struggled to compete.

Focusing on the LEO computer makes this a human scale story with central cast of characters, but it also provides a wider view of the field in the years after the Second World War. The book makes clear how J. Lyons & Co had a system of management, and personnel in place which were ripe for computerisation; the developments in the 1930s made it clear that electronic computers were in the air. Large scale failures of computer systems in both public and private sectors are onging, John Simmons was rather insightful in his intimate coupling between business process and software system.

References

1. My Evernotes are here

2. The web page of the Leo Computer Society is http://www.leo-computers.org.uk/

Jul 02 2012

Book Review: The Geek Manifesto by Mark Henderson

The-Geek-ManifestoThis review is of Mark Henderson’s book “The Geek Manifesto: Why Science Matters“. It starts with Simon Singh’s lengthy libel battle with the British Chiropractic Association, which sets the scene for the rest of the book.

In some senses this is a book about “my people”, many of the events described were ones I watched unfold online. For example, I wrote back here, about David Nutt’s sacking from the Advisory Council on the Misuse of Drugs. I remember the Boots 10:23 homeopathy protests in which geeks overdosed on homeopathic remedies, I even got ever so slightly involved in Science is Vital. The acknowledgements go out to many people I follow on twitter, and the links to other books I have read, “Adapt” by Tim Harford and “Bad Science” by Ben Goldacre, are explicit. I’d also add “Freakonomics” by  Steven D. Levitt and Stephen J. Dubner to this genre.

After the opening Simon Singh case there are chapters on the role of science in politics, government, the media, the economy, education, court, healthcare, and environmentalism. Random fact I picked up: only two scientists have appeared on the BBC Question Time programme in the last 8 years – somewhat shocking given the wide roster of the great and the good who appear on the programme. I liked the practical examples of reducing crime in Cardiff, led by Professor Jonathan Sheperd, a maxillofacial surgeon frustrated and distressed by the number of young people admitted through Accident and Emergency with severe cuts from pub brawls. He collected detailed evidence of incidents which he passed on to police, later publishing research on the outcome of this approach by comparison with a similar city without such intervention.

I also liked the stories from the University of Southampton on fibre optic research and Shankar Balasubramanian (at Cambridge University), whose gene sequencing company, Solexa was recently acquired for $600million. Too often scientists make the public assertion that spending money on research benefits the economy, but then say that you can’t possibly direct them into particular areas of research – the old blue skies argument on which I blogged here and here. These case studies are convincing on the benefits of longer term, university-based research.

The section on climate change and environmentalism fits somewhat with my opinions – in principle I am green but find the official face of the environmental movement (Greenpeace, Friends of the Earth, the Green Party, The Soil Association) difficult because they go beyond the environment to an anti-capitalist world view in which good science is optional; particularly in campaigns against genetically modified crops and nuclear power. However I don’t believe the Greens can be blamed for the, typically, right-wing opposition to the consensus on anthropogenic  climate change. I wrote a bit about climate change here. This also touches a little on the Sense About Science organisation, one mentioned several times through the book, they are no doubt useful but I have my suspicions about some of their positions, particularly on climate change – this article in The Skeptic captures some of that unease.

The book is very well described as a manifesto: it’s aimed at the geeks of the title. It picks up on a theme of increased levels of activism amongst scientists, a growing skeptic movement and the newly formed comedy / science intersection (Dara O’Brien, Robin Ince and so forth). I’m a scientist, I’ve been a scientist for 20 or so years, and I’m undeniably geeky – I write programs for fun, yet I find the “geek” label uncomfortable.

There has been a twitter campaign to send this book to every single MP, all I can say is I hope they don’t read the second chapter. Henderson, a historian by training, seems rather overwhelmed by the forensic powers of scientists and dismisses the idea that anyone else might have them. I think his attitude is summarised in his reference to introducing more scientists to parliament which will apparently

“…rapidly raise the game of the non-scientists around them”

I’m a scientist, and I find this embarrassingly patronising. His remedy for bad science in the media is rather more subtle and nuanced than his approach to politicians. I think in the end, in politics, he highlights some of the important things – the need to engage with MPs rather than leave it to others; the need to engage early when positions are not set in stone and the need to recognise that MPs face other pressures: a recent Early Day Motion in support of homeopathy is a case in point: many MPs signed because they believed, that many of their constituents were passionately in favour of it, the support of Prince Charles probably helped them with their decision too.

The Behavioural Insights Unit in the Cabinet has a recent paper “Test, Learn, Adapt: Developing Public Policy with Randomised Controlled Trials” by Laura Haynes, Owain Service, Ben Goldacre and David Torgerson (pdf) which is exactly the approach to government that Henderson is promoting. It perhaps highlights that a frontal assault on MPs is not the way in: the civil service is important. A second strand, which I would propose, is casting the whole experimenting thing into a business context. One of my own political preferences is for governments that do things competently (regardless of political tendency), in business this might be labelled something like “Excellent Execution”. Doing things competently isn’t a particular skill of scientists: it’s something everyone can aspire to, and scientists by no means have a monopoly on the routes to competence, or even universally exhibit themselves.

Once again, I am tricked by Kindle – the text of this book ends at about 60%, it is very heavily referenced!

Jun 22 2012

Book Review: Huygens–The Man Behind the Principle by C.D. Andriesse

huygens-man-behind-principle-c-d-andriesseThis post is a review of C.D. Andriesse’s biography “Huygens: The Man Behind the Principle”. Huygens Principle concerns the propagation of light but he carried out a wide range of research, including work on clocks, Saturn (discovering its moon “Titan” and hypothesizing the existence of its rings), buoyancy, circular motion, collisions, musical scales and pendulums. Huygens has made passing appearances in my blog posts on the French Académie des Sciences, on telescopes and also on clocks.

On the face of it is surprising that he is not better known, looking around for biographies of him one finds a rather short list. Andriesse puts this down to much of the personal documentation being in Dutch. The scientist in me feels there should be some quantitative way of measuring how “well known” a historical figure is now, and how “important” they were – I suspect this is an impossible programme. On completing the book I suspect a couple of factors play a part here: Huygens represents something of a transitional figure between the work of Galileo/Descartes, and Newton/Leibniz. Similarly his practical work on clocks and telescopes was impressive for its time but superseded not long thereafter. What we do now in physics owes much more to Newton than to Galileo, furthermore Newton although not prolific published more promptly than Huygens and was President of the Royal Society for 20 or so years before his death in post, whilst Huygens left L’Académie des Sciences sometime before his death in not particularly auspicious circumstances. It isn’t entirely clear whilst reading the book, but it becomes obvious that frequently Huygens’ work was done over long periods and only published quite a long time after it was started, often posthumously.

Huygens was born in the Hague in 1629 and died 1695. Christiaan Huygens’ father, Constantijn was a senior Dutch diplomat and a regular correspondent with René Descartes. Constantijn also met Francis Bacon (and was clearly impressed by him), Bacon and Descartes were important in shaping the development of science in the early 17th century. Bacon in particular set the scene for the way of doing science both in the Royal Society and  L’Académie des Sciences. Constantijn set his son off on a regime of study in the classics, with a view to him becoming a lawyer and following in his footsteps as a diplomat. Sometime around 1643, when Christiaan was 14 years old he started to show promise in mathematics.

Huygens senior provided introductions to Marin Mersenne who introduced him to those circles who became the Académie des Sciences in France. Christiaan Huygens was a paid director of science at L’Académie from its foundation in 1666 until he was excluded from it shortly after the death of Jean-Baptiste Colbert, founder of the organisation and his principle patron, in 1683. The exclusion arose from a combination of the loss of this patron, religious differences, absence due to illness, personal vendettas, opposition to membership of any foreigner and his demand for higher remuneration. Aside from this period at L’Académie, Huygens appears to have lived on the wealth and position of his father.

There’s no doubt that he made significant contributions in the area of mechanics, going beyond what Galileo and Descartes had done but his work was superseded almost immediately by that of Newton, and Leibniz, particularly in the methods of calculus which they developed. Calculus is a tool which makes much of the complex geometrical work that Huygens did obsolete. Leibniz was an informal pupil of Huygens, and they kept up a lengthy correspondence. He also had some exposure to Isaac Newton via the Royal Society.

Andriesse claims that Huygens wrote the first physics formula, relating to collisions. I think we should probably take this with a pinch of salt, but looking at the work he did do on circular motion, collisions, buoyancy, the motion of the pendulum and the shape of a catenary as well as his work on optics it is all very familiar to those that studied physics (at least to the age of 18).

Alongside his mathematical and theoretical physics work, Huygens also made contributions to the development of both clocks and telescopes. He introduced the pendulum clock, and a design of his was tested for determining the longitude by the Dutch East India Company. In practical terms this was not successful but it was a valiant first try. He also made lenses and constructed his own telescopes, here he appears to have been a competent technician and an able theoretician but not reaching the level of Newton, who constructed his own reflecting telescope – the first practical example of its type which was not exceeded for some 30 years or so.

This is a detailed biography of Huygens, drawing heavily on his personal correspondence and covering his scientific achievements in some depth, in the manner of Abraham Pais biography of Einstein. Although the book is pretty readable, the style is odd in places – Huygens is referred to frequently as “”Titan” without any real explanation as to why – it may be that in the original Dutch version, entitled “Titan kan niet slapen” (“Titan can not sleep”) this is a bit more obvious. The author also throws in the odd “Iris” when referring obliquely to sex (at least I think that’s what he’s doing!). Occasionally bits of information are scattered through the text, so we learn when Huygens is born and only 10 pages later do we learn where. There is no strong distinction of when Huygens started working on a publication and when it was actually published.

Perhaps more seriously Andriesse makes an attempt at Freudian analysis of some of Huygens illness, I’m no expert in this but I suspect this approach would be considered out-dated these days. It is also here that the translation perhaps wobbles a bit, with Huygens described as having “symptoms of the hypochondriac” which I think may be a mistranslation of melancholia hypochondriaca which I believe refers more generally to mental illness than the specific modern “hypochondria”.

This said, Andriesse’s biography of Huygens is well worth reading. Christiaan Huygens himself is an interesting subject who made important scientific discoveries across a range of areas.

Footnotes

My Evernotes for the book are here.

Jun 01 2012

Book Review: Visualize This by Nathan Yau

9780470944882 cover.inddThis book review is of Nathan Yau’s “Visualize This: The FlowingData Guide to Design, Visualization and Statistics”. It grows out of Yau’s blog: flowingdata.com, which I recommend, and also his experience in preparing graphics for The New York Times, amongst others.

The book is a run-through of pragmatic methods in visualisation, focusing on practical means of achieving ends rather more abstract design principles for data visualisation; if you want that then I recommend Tufte’s “The Visual Display of Quantitative Information”.

The book covers a bit of data scraping, extracting useful numerical data from disparate sources, as Yau comments this is the thing that takes the time in this type of activity. It also details methods for visualising time series data, proportions, geographic data and so forth.

The key tools involved are the R and Python programming languages; I already have these installed in the form of R Studio and Python(x,y), distributions which provide an environment that looks like the Matlab one with which I have long been familiar with but which sadly is somewhat expensive for a hobby programmer. Alongside this are the freely available Processing language and the Protovis Javascript library which are good for interactive, online visualisations, and the commercial packages Adobe Illustrator, for vector graphic editing, and Adobe Flash Builder for interactive web graphics. Again these are tools I find out of my range financially for my personal use although Inkscape seems to be a good substitute for Illustrator.

With no prior knowledge of Flash and no Flash Builder, I found the sections on Flash a bit bewildering. It also highlights how perhaps this will be a book very distinctively of its time, with Apple no longer supporting Flash on iPhone its quite possible that the language will die out. And I notice on visiting the Protovis website that this is no longer under development: the authors have moved on to D3.js, Openzoom which is also mentioned is no longer supported. Python has been around for sometime now and is the lightweight language of choice for many scientists, similarly R has been around for a while and is increasing in popularity.

You won’t learn to program from this book: if you can already program you’ll see that R is a nice language in which to quickly make a wide range of plots. If you can’t program then you may be surprised how few commands R requires to produce impressive results. As someone who is a beginner in R, the examples are a nice tour of what is possible and some little tricks, such as the fact that plot functions don’t take data frames as arguments: you need to extract arrays.

As well as programming the book also includes references to a range of data sources and online tools, for example colorbrewer2.org – a tool for selecting colour schemes, and links to the various mapping APIs.

Readers of this blog will know that I am an avid data scraper and visualiser myself, and in a sense this book is an overview of that way of working – in fact I see I referenced flowingdata in my attempts to colour in maps (here).

The big thing I learned from the book in terms of workflow is the application of a vector graphics package, such as Adobe Illustrator or, Inkscape, to tidy up basic graphics produced in R. This strikes me as a very good idea, I’ve spent many a frustrating hour trying to get charts looking just right in the programming or plotting language of my choice and now I discover that the professionals use a shortcut! A quick check shows that R exports to PDF, which Inkscape can read.

Stylistically the book is exceedingly chatty, including even the odd um and huh, which helps make it quick and easy read although is a little grating. Many of the examples are also available over on flowingdata.com, although I notice that some are only accessible for paid membership. You might want to see the book as a way of showing your appreciation for the blog in physical and monetary form.

Look out for better looking visualisations from me in the future!