Day 23 - The enigma of intelligence

Alan Turing

“Alan Turing: The enigma of intelligence” was a book by Andrew Hodges which, I am surprised to note, was published in 1985. I can’t believe I read it 30 years ago but I must have done. There are several shameful episodes in British history and I would not wish to rank them in order of shamefulness. If I did, however, I would have to rake the hounding of Alan Turing, eventually to his death, as up there with the most shameful.

Turing is sometimes referred to as the Father of Computing and it was at Bletchley Park where we went today where Turing worked on cracking the enigma code that the Germans used in the Second World War. He explored the concepts of “algorithms” and “computation” by using what is now called a “Turing machine”. This is a hypothetical device that manipulates symbols on a strip of tape according to explicit rules (we would call this a program today). Despite its simplicity, a Turing machine can be adapted to simulate the logic of any computer program.

Bletchley Park is near Milton Keynes which is a 25 minute drive from my parents. Milton Keynes was created in the 1906s when the government decided additional towns in the south-east of England were needed to relieve housing congestion in London. I remember the joke that there were concrete cows at MK (as it is sometimes known) because there were no real ones to be seen. Some overspill housing had been constructed in Bletchley in the 1950s which may have been why they put MK where it is.

Milton Keynes Station - we know what Dr Johnson might have said about this rail track and this is the track to the South!

Blethchley Park (www.bletchleypark.org.uk) was the heart of the British efforts (largely successful) to decipher German (and Italian) signals so that they could get a jump of the Germans. The story started before the War in August 1938 when ‘Captain Ridley's Shooting Party’ turned up at this Buckinghamshire country house to see if it would be suitable for intelligence activity.

The mansion at Bletchley Park

Google seems to have some sort of sponsorship or support deal with Bletchley Park but it is not very high profile. There is a running slideshow at the entrance which celebrates the fact that it was the diversity of people who worked at Bletchley that led to its success.

On the face of it looking around a bunch of old buildings that were used by a load of mathematicians, statisticians and other oddballs may not strike one as particularly interesting. For me, as a mathematician, I get the ideas behind deciphering. But for the non-mathematician … ? As it happened they have done a truly brilliant job of creating a set of displays and interactive screens that are entertaining and informative.

A BSA bike presumably from the late 1930s - I assume that some of our readers will identify it but I can't

A set of spare rotors for an enigma machine. The first machines had three rotors which gave  

159 x 10¹⁸ possible settings (that's 159 with 18 noughts after it). Later machines had four rotors which increased that number

Ten years to the day before I was born Churchill was asking to see all the decrypts in person. He must have given up on that one pretty quickly - he would have been swamped!!

Apart from the main house – which I recall housed the administrative types – there were constructed in the grounds a number of huts. Hut 8 was the hut where Turing worked and they had recreated his office.

Entering these huts one is faced with a long, dark and dingy corridor which is as it must have been – even down to what looked like (but cannot have been) period linoleum on the floor. There were doors leading off this corridor and each was a separate office. This was way before open plan offices of course.

The door to the great man's office

The great man is alleged to have chained his enamel tea mug to the radiator to prevent someone from nicking it. I don't low if this is true but it seems to me this would be the mark of a great eccentric or someone who was incredibly bright.

And inside, not surprisingly utilitarian 

Turing's famous paper (1936) is called "On computable numbers, with an application to the Entscheidingsproblem" (www.cs.virginia.edu/~robins/Turing_Paper_1936.pdf) and is readable with a little effort by anyone with undergraduate mathematics. The Entscheidungsproblem is about asking for an algorithm to decide whether a given statement is provable from a set of axioms axioms using the rules of logic. Turing showed in his paper - as an aside - that the Entscheidungsproblem has no solution. It's worth looking at The Rutherford Journal (www.rutherfordjournal.org/article030108.html) for a description of the computer (it was called the Bombe) that Turing and others developed to run deciphering algorithms.

And remember ... walls have ears!!

I think he got that about right ... which is why mathematics and the arts are so closely related. In my opinion mathematics is not a science, it is an art. 

Answers on a postage stamp, please!!

A message awaiting decryption. There were several of these "W/T red forms" on display. (W/T I think stands for wireless telegraphy.) Why at the bottom it says "Do Not Use Left Margin" I could not work out as none of them seemed to have anything in the left margin. You would assume someone might write something there after the form was processed, but we didn't see any examples

What happened to the Stationary Office? And what happened to quarto exercise books? We will never know.

We had not realised just how much there was to see but unfortunately we were short of time as today we are flying back. For anyone who wants a full day’s activity this would be a place to visit.

We lunched with my parents. I had been concerned about the M25 car park so we left in plenty of time only to find (of course) that there was no traffic and our journey time was only an hour or so. We dumped the fancy car and checked in about 5 hours early but we have got on an earlier flight which means that we have more time at Dubai (unless there’s another earlier one!!).

The G busy researching stuff on the iPad in the Emirates lounge

So now it is head down and bum up as we enter the travelling processes.