If you were asked to name the most important scientist of the 20th century, you would probably say Albert Einstein – after snorting with derision at the simplistic question, of course.

Terry Wardrop, who teaches computer science at St. Paul’s School in Concord, has another name for you to consider: Alan Turing.

“He should have been as big, as popular, as important as Einstein. It was the secrecy acts and his tragic demise that stopped that from happening,” said Wardrop, whose interest in Turing dates back to 1978, when he wrote a Turing Machine simulator on an old PDP-11/03 for his computer science degree.

If you want to consider Turing a bit more, why not come to the Red River Theatres in Concord on Tuesday night, when Wardrop and I will hold a discussion about Turing after a showing of “The Imitation Game.” The just-released Hollywood movie concerns Turing’s code-busting exploits in World War II.

The fact that Turing is the subject of a big-budget film, and is played by a sexy guy like Benedict Cumberbatch (aka BBC’s Sherlock), is an indication of how popular he has become, even if he isn’t quite at the Einsteinian level.

It’s not the only indication, either. His clever Turing Test, used to distinguish between humans and computers, has become a cultural staple, and the laboratory where Turing and many others helped crack Nazi codes has been turned into a major museum in Britain, so popular it generated a huge fight over who would run it.

This popularity is fairly recent, however. Twenty years ago, the name Alan Turing would have left you baffled unless you had studied enough computer science to hear of the Turing Machine, his thought experiment that underlies much of computer science.

Turing’s reputation began to grow in 1983, when Andrew Hodges published “Alan Turing: The Enigma,” one of the best scientific biographies ever written.

At the time nobody had heard about the World War II project in Britain to break the “unbreakable” Nazi code produced by the Enigma machine, because it had only just been released from the shroud of Britain’s Official Secrets Act. The book was a revelation.

Through it we learned of the Enigma project, which could legitimately be said to have shortened World War II by years, of Turing’s technical and mathematical role in helping develop the first computers, and of his mysterious death after being hounded by British authorities because he was a homosexual.

It was riveting, fascinating and important, and it launched what has become a minor industry of Turing Appreciation.

Wardrop says this popularity shouldn’t blind us to Turing’s importance in creating computer science, the defining technology of the past half century.

The Turing Test is a perfect example. At the time it was published in a 1950 paper, there was huge and convoluted debate over which mathematical and technical criteria should be used to determine whether computers can think.

Turing’s paper – which Wardrop says is easily readable even by laymen, despite its deep insight – broke right through all that. It proposed an “imitation game” (hence the movie title). If a computer could fool you into believing that it was thinking, then it was thinking.

“People who knew him, they would say, that was his genius: To look at a problem and notice a thing that later on you would say was obvious, but which nobody else saw, that would allow a jump to be made in terms of sophistication,” said Wardrop.

The Turing Machine is an even more important idea, but takes too long to describe here. We can go into detail about it – or anything else, really – in our post-movie discussion, if the audience wishes. The movie starts at 6 p.m. and last 114 minutes, with the discussion afterward.

It costs $12, as it’s something of a fundraiser for the non-profit theater. (No, I’m not getting paid. Sigh.)

It should be fascinating. Sort of like our science cafes, with just as much intellectual fun. Plus, popcorn!

GraniteGeek appears Mondays in The Telegraph. David Brooks can be reached at 594-6531, dbrooks@
nashuatelegraph.com or
@GraniteGeek.