On the 15th of May 1951 the BBC broadcast a short lecture by the mathematician Alan Turing under the title Can Computers Think? This was a part of a series of lectures on the emerging science of computing which featured other pioneers of the time, including Douglas Hartree, Max Newman, Freddie Williams and Maurice Wilkes. Together they represented major new projects in computing at the Universities of Cambridge and Manchester. Unfortunately these recordings no longer exist, along with all other recordings of Alan Turing. So I decided to rerecord Turing’s lecture from his original script.

This recording came about when I was working the Codebreakers and Groundbreakers exhibition for The Fitzwilliam Museum, Cambridge. The exhibition focuses on two codebreakers, the first being Michael Ventris, an architect and linguist who in 1952 deciphered the ancient Greek script known as Linear B. This breakthrough added about 500 years to our knowledge of ancient Greek history and is considered one of the great advances in classical scholarships.

The second codebreaker featured in the Fitzwilliam exhibition is Alan Turing, one of the leading British codebreakers at Bletchley Park who broke the German code machine Enigma during World War II. This gang of codebreakers was a mix of mathematicians, linguists, and puzzle-solvers. One of our aims for the exhibition is to show how this collaboration and sharing of skills made breaking Enigma possible.

The exhibition will run until the beginning of February 2018, and features unique Linear B clay tablets from the palace at Knossos, Crete; a rare U-boat Enigma machine and British TypeX machine both on loan from GCHQ; as well as various archival material from Michael Ventris and Alan Turing.

The exhibition also contains audio extracts from a BBC broadcast from Michael Ventris. So it was disappointing that we could not feature an equivalent audio extract from Alan Turing. However, the Turing archives at King’s College, Cambridge do contain Turing’s script for Can Computer’s Think? This script is available online via the Turing Digital Archive.

I was surprised how good Turing’s script was. Instead of the dense, academic language I feared, the script was a clear and simple explanation of the future of computing written for the layman – with perhaps the exception of the long desert island analogy, which I did not get on with at all. The second thing that surprised me was, for a script written in 1951, how current it all seemed. Turing is often described as ahead of his time, and the evidence is right here.

Turing talks about the computer’s ability to imitate any kind of calculating machine, a property known as universality, and considers if a machine will ever be able to imitate a brain. Turing then goes on to discuss whether a computer is capable of originality, or indeed free-will.

Turing then makes one firm prediction, that by the end of the 20th century computers would be able to answer questions in a manner indistinguishable from a human being – this is the famous Turing test. Turing’s prediction may have been a couple of decades early, but with the rise of digital assistants I would have to say he was completely right.

I was fascinated by Turing’s prediction of how unsettling it would be to design machines to look like people, an effect we now call the Uncanny Valley. Turing also saw no limits to what a computer would be able to achieve, and saw the future of programming to be closer to that of teaching, which is what we see today in the areas of Deep Learning and Neural Networks.

Throughout the lecture, Turing’s language is friendly and inclusive. He is also charmingly humble, admitting there are many other opinions and that these were just his own. I was also pleased to see Turing acknowledge the legacy of computing with a quotation from Ada Lovelace speaking about Charles Babbage’s Analytical Engine. I found the script so pleasing that I decided it would be nice to rerecord it so that new audiences would be able to hear Turing’s words as he intended.

Allan Jones has written more on this series of broadcasts by the BBC.

The Codebreakers and Groundbreakers exhibition is open at the Fitzwilliam Museum, Cambridge until Sunday the 4th of February 2018.

A transcript of the broadcast (PDF) has been submitted by Lewis Baxter.