I have been woefully remiss. Turing’s 100th Birthday came and passed last June 23 and I didn’t post a single thing in this blog named after his famous (well, I changed it a little) test for Artificial Intelligence. Exactly what did Alan Turing do?
He’s the father of computer science and artificial intelligence. In layman’s terms, he thought a computer can solve any sort of problem as long as you can break down the problem into simple step-by-step calculations called an algorithm.
He also thought of a Universal Machine (nowadays called a Universal Turing Machine) to demonstrate his idea. It was never meant to be built, but it was a ‘thought experiment’ (Albert Einstein popularized the idea of using a thought experiment if a real experiment can’t be performed), of how a computer works.
The Turing machine can be described as a simple box that can read symbols. The box is attached to an infinitely long tape with symbols. Depending on what symbols it reads, the box will move forward or backward along the tape, reading, memorizing, copying or writing on the tape.
And that’s it. From that simple idea, the whole field of computer science emerged.
His Universal Machine was the theoretical breakthrough that led to the Stored Program Computer. A Stored Program Computer is a very simple idea. Before the Stored Program Computer, computers were thought of as specialist machines. A calculator is used for calculating, right? You don’t use a calculator to take pictures. But the Stored Program Computer can change its purpose depending on the application you open. If you open your Photoshop application, you can fix photos. If you open iTunes, you listen to music. If you open Windows Media Player, you play videos. If you open Plants vs. Zombies, you play games. You don’t need to open up a computer and add parts or change the wiring . Suddenly, the computer becomes some kind of Swiss Army Knife among machines, able to do almost everything you want as long as you switch the application program to use.
All computers nowadays are Stored Program Computers, from your smart cellphones, to massively parallel supercomputers, to automated teller machines, to iPads and ebook readers. And all owe their theoretical origin from Turing’s Universal Machine.
What else did Turing do? He was a codebreaker at Bletchley Park, among the mathematicians who broke the Enigma code for Hitler’s top secret radio transmissions. Their work help win World War 2.
Turing also invented the Turing Test (which, slightly modified, is the name of this blog). It’s a test to see if a computer is self-aware and sentient, in short, an artificial intelligence. Like his Universal Machine, the test is easy. Put a computer in one room, a man in another room, and an interviewer in a third room. The interviewer can read text messages from the man and the computer. If the interviewer, after a long conversation, can’t tell the difference between the two, the computer has intelligence.
Turing was gay, which was illegal in the United Kingdom at the time. To avoid jail, he accepted chemical castration (taking female hormones to reduce libido), and committed suicide two years later at 41 (though his family disputes this).
British Prime Minister Gordon Brown, a few years short of the centenary of Turing’s birth, made an official apology on behalf of the government about “the appalling way he was treated”.
Some good Turing links if you want to know more about this man:
A website by Andrew Hodges, a biographer of Turing: http://www.turing.org.uk/turing/
The wikipedia entry: http://en.wikipedia.org/wiki/Alan_Turing
An interesting essay on artificial intelligence and how far we need to go before achieving it: http://www.zdnet.com/blog/btl/what-happened-to-turings-thinking-machines/80639?tag=mantle_skin;content