Monday, June 7, 2010

June 7th – Saint Alan Turing Day

Story: When I used to teach philosophy, I called Alan Turing “the logician who saved the world twice” it is an exaggeration, but not much of one. Alan Turing was one of the great mathematical minds of the 20th century and spread his talents to philosophy, and chemistry as well. He was a homosexual, and out to himself fairly young. When his first love interest died from complications from Bovine TB, while he was a teen his faith was shattered and he became a lifelong atheist. He got a degree in math and at the ripe age of 24 published a paper pushing some of the boundaries of computability theory. He was send to Princeton to study at the Institute for Advanced Studies, under Alonzo Church, and got his Ph. D. in 1938.

Soon after WWII broke out and as it happened, Turing played a key role in the war. He became the star cryptoanalyst of British intelligence, and eventually of Allied intelligence. Straight away he invented a machine that made cracking the German Enigma cipher (which was designed to be constantly changing) easier. His mathematical work had focused on the limits of what can be done with mechanical computational devices, but in fact during the War he developed or helped develop numerous mathematical code breaking devices, several devices for secure coded transmission, and several new mathematical approaches to code breaking having nothing to do with his computational theories (Bayesian approaches, and an approach involving the principle of ex falso quadlibet). It is no exaggeration to say that the Allied cryptological superiority was a key part of why they won WWII, or that Turing personally was a key part of the Allies cryptological superiority. That was the first time he changed the world, although it was all strictly hush-hush for decades.

Turing’s own mathematical work was foundational, original and searching. He wanted to explore the theoretical limits of what a computational device can, and cannot do. He invented a type of logical computational device, which we now call a Turing machine, and proved that anything that can be computed by any device can be computed by a Turing machine too (albeit vastly less efficiently in many cases). And it turns out that, his work together with Godel, and Church’s means that there are a number of tasks that even the most powerful and sophisticated computer can never do.

Turing was intimately involved in the transition for mechanical computation devices to electronic ones. He was also intimately involved in the transition from building special purpose computational devices, to building fully general ones. Turing devised the world’s very first compiling program, and designed on paper an electronic computer that could run any program. This was the nucleus of ENIAC the world’s first Turing-complete physical computer. The closer one looks at the history of early computing, the clearer it becomes, that like with the automobile, no one person can really be considered the inventor. Thing progressed in many small stages, and many, many people and labs were part of the story. But no one can doubt that Alan Turing was central to the story, in theoretical ways, in practical hands-on ways, in finding applications and solving engineering problems, as well as in seeing what can be done. Turing’s invention of the compiler program is probably the closest thing there is to the beginning of modern computing. And by founding modern computer science he changed the world again.

And now we get to his shame and martyrdom. In 1952, one of his lovers helped an accomplice break into Turing’s house, and in the police investigation Turing admitted that he had slept with the man, which was illegal in Britain in 1952, but rarely prosecuted and rarely punished heavily. The judge in the case, was particularly upset that Turing had not enlisted and helped his country in its time of desperate need, and demanded clarification as to why. Turing begged the government for a letter, that without giving away the secrets of just how much Turing had helped in WWII, would say that Turing had been serving his country and that his government was happy with his service. They refused. Indeed, although he had been awarded the Order of the British Empire, in 1945 for his war-time services, he was forbidden to share this fact with anyone without high-security clearance. The judge publicly called Turing a coward and a reprobate and gave him the maximum sentence of 10 years in jail. Shortly after, his lawyers cut a deal to suspend the sentence in return for house arrest and an experimental “chemical castration” hormone treatment.

From 1952-54 Turing was despondent, friendless, in exile, depressed and see-sawing around emotionally and physically in response to the drugs he was on. He worked some on chemistry and mathematical biology, and indeed made several significant contributions there. On June 7th, 1954 he died of cyanide poisoning, with a half eaten apple nearby that was never tested for poison, and no note. There are many theories floated about what exactly happened. The inquest ruled that Turing had committed suicide. If so, his recent trial, public shaming, arrest, enforced experimental drug-regime, and inability to defend himself without violating national security are surely to blame. For my part, I consider him a martyr to the culture of secrecy surrounding national security since WWII. His mother argued that his poisoning was accidental, and resulted from incautious handling of the chemicals he was researching with in his lab. Some writers have speculated that he was assassinated by National Security forces of some kind or another to keep some secret, or to prevent him from inventing something else dangerous, like a new code or a new code breaker. Another theory is that he intentionally re-enacted the scene from Snow White with the poison apple.

Turing has been honored in many ways since his death. He ranked 21st in a 2002 BBC poll of the 100 most influential Britons of all time. In 1999, Time named him one of 100 most influential people of the 20th century, saying “The fact remains that everyone who taps at a keyboard, opening a spreadsheet or a word-processing program, is working on an incarnation of a Turing machine." On Sept 10, 2009 Prime Minister Gordon Brown, publicly apologized for the British Government’s failure to intercede on Turing’s behalf at his trial, and thanked him once again for his many services to his country.

I am grateful for the Turing theory of computability.
I am grateful for Turing’s proof that there are some things that computers will never be able to do.
I am grateful for Turing’s work to build functioning electronic computers, from math, to logic, to programming to engineering.
I am grateful for Turing’s philosophical speculations on artificial intelligence and the “Turing Test”
I am grateful for Turing’s work to aide the Allies in WWII
I am grateful for a symbol of gay pride in math and science
I am grateful for the kind of deep patriotism that would lead a man to keep a secret, even while it was destroying him
I am grateful for those who died in shame, while doing good, even if their secret contributions have not come to light, as Turing’s did.

Other Notable Events for the day
Gandhi performs his first act of civil disobedience against Apartheid, while he is a young lawyer in South Africa. The Supreme Court decision in Griswold vs Connecticut 1965 effectively legalizes contraception use by married couples.
Birth of Herman Wells, IU president who among other things defended Kinsey, birth of Nikki Giovanni (poet), Prince (musician), Damian Hirst (conceptual artist), Dave Navarro (musician), death of Chief Seattle, and Henry Miller (dramatist)

1 comment:

  1. It is a shame that you do not mention that Alan was English and was born in England more clearly and explicitly in this otherwise informative piece.

    He only went to US to meet Claude Shannon on a couple of occasions and discuss the issues that Shannon was working on with respect to artillery ranging.