Turing, Alan Mathison (1912-1954)

Appeared in: Lecture 10

Fifty years ago, Alan Turing predicted that by the year 2000, computers would have over a billion bits of memory. His prediction turned out to be more accurate than he ever could have imagined: a typical PC bought in January of 2000 contained exactly 128 MB of RAM, which is just a little more than a billion bits. While the mechanics of building a computer today are not something anyone could have imagined so long ago, the foundations of theoretical computer science have hardly changed since Turing's time, indicating just how much vision and foresight he really had.

Turing also predicted that by the year 2000, computers would be so intelligent that they could fool people into thinking they were humans more than 70% of the time if they tried. In the so-called "Turing Test", a judge would interact with two subjects, one a person and one a computer, and both would try to convince the judge that they were the human and the other was a computer. The computer has passed the Turing Test if it can consistently fool the judge some fraction of the time. Unfortunately, no computer has yet passed the Turing Test, and you can see the results of the latest contest (January 2000) that competed six computers against four humans: Loebner Prize 2000 - Turing Test Results It's particularly fun to read the transcripts to see what the computers said.

Though he is now one of the most venerated of all scientists in history, during his lifetime he did not receive as much fame and glory as he deserved. Possibly the happiest time of his life was between 1939 and 1945 at Bletchley Park, where he helped break the German secret codes and ended up designing and building a machine to automatically break the codes. Unfortunately, his contributions to the war effort were highly classified, and afterwards he was not able to claim credit for most of his amazing contributions. Turing was also a homosexual, and when he finally confessed this in 1952 he suffered very much as a result because at the time homosexuality was not very well understood or accepted.

Turing died in 1954 of eating an apple that had been poisoned with potassium cyanide. It is not known whether this was self-administered or an accident.

Turing was a fascinating character, and there are far too many details of his life to cover here. (For example, he was an amazing runner, nearly making it to the Olympics.) There have been countless biographies published of him recently, but if you are interested in some pleasure reading that includes Alan Turing as one of the characters, check out Cryptonomicon by Neal Stephenson (see below). The book is fun and exciting enough as a work of fiction, but the interesting historical and biographical information combined with many hi-tech subjects integral to the plot make it especially cool for those interested in computer science or mathematics.

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