*Image reproduced with the Permission of James Evans Illustration.

Sintija Jurkevica

Could a computer ever be able to enjoy strawberries and cream? Could a computer ever make a human fall in love with it? These are types of questions Alan Turing (1912-1954) might ask one whole-heartedly at a dinner party, thereby unfolding the eccentricity of the genius himself. By profession, Turing was a distinguished British mathematician, logistician and philosopher, who pioneered the field of computer science, whilst his persona has been characterized as petulant and reserved, concealing a world of innocence and passion for nature and truth.

In the celebration of the 50 year milestone reached after the development of Sexual Offences Act 1967, highlighted in this article are some of the most influential Turing’s achievements, followed by a short biography on his personal life as a man who found himself attracted to other men at a time when same-sex attraction was illegal.

* #1: The Universal Turing Machine*

Suppose a world in which computation, crudely defined as a mathematical calculation, is only carried out by humans. This almost begs one to ask the seemingly obvious question: could a physical machine be engineered to carry out simple calculations? And yet, at the technological limits of 20^{th} century, this was not so obvious. Turing was fascinated by the possibility of building such a machine and in 1936 he conceptualised a mathematical model of a computer, named the Turing Machine.

The Turing Machine was conceived as an infinitely long paper tape divided into squares with erasable digits written on it which would act as storable memory of an output. The digits on the tape would be recognised and printed or erased by a read and print tape. Hypothetically, when given an instruction, as simple as the calculation of 2 + 2, the machine would read the digits individually and alter them appropriately following the set rules until the calculation is finished. For example the Turing Machine would re-read the tape of digits until it finds a solution of 4 when instructed to calculate 2 + 2.

Whilst each Turing Machine can only follow a single set of rules, namely a single program, a Universal Turing Machine can hypothetically compute an infinite amount of programs when its sets of instructions have been changed, or re-programmed. This concept of a universal, programmable computer has laid the foundation of the modern theory of computation, where a single machine can carry out the task of interpreting and obeying a program, just like, in essence, a standard digital computer does. Only 9 years later did the electronic technology evolve to transfer Turing’s mathematical concepts and logical ideas into practice engineering to demonstrate the feasibility and usefulness of such a device.

Upon a closer philosophical enquiry, one realises that Turing’s arguments for building the UTM connects logical instruction, something regarded as cognitive, with materiality of a physical machine; this is arguably Turing’s most significant legacy to the world that will influence the many generations after him. Throughout his lifetime, Turing would also relate his mathematical work to the functioning of the mind. For example, he regarded the building of UTM as “building a brain”, and has written an influential philosophical paper titled *Computing Machinery and Intelligence*, that has inspired the field of Artificial Intelligence.

* #2: Cracking the Unbreakable Enigma *

During the Second World War, Turing worked at Bletchley Park, the British cryptanalytic headquarters. There, he designed and helped to build a functioning decryption system called the Turing-Welchman “Bombe”, which initially read the German Luftwaffe air force signals. Later, the codes, deemed as impossible to decrypt, generated by the German “Enigma” machine used in German naval communications, were cracked by Turing in 1939. Turing’s section ‘Hut 8’ deciphered Naval and U-boat messages on an industrial scale, and its influence has been argued to contribute towards the Allied victory over The Axis.

* #3: Work on Non-Linear Dynamic Theory*

During his childhood, Turing was fascinated by nature and showed curious philosophical enquiry, exercising his ability to make connections between seemingly unrelated concepts. He would make degree level notes on the theory of relativity at school and pondered whether quantum-mechanical theory could explain the relationship between mind and physical matter during his undergraduate years at Cambridge.

In his older years working at Manchester University, Turing used the computers developed there to explain universal patterns in nature by mathematics, and published another classic paper titled ‘*The Chemical Basis of Morphogenesis’* in 1952. His theory of growth and form in biology explains how the so called Turing patterns, such as leopard stripes and the spirals of snail shells, emerge from an initial mass of uniform matter.

* Turing’s Relationships*

It was during his years at a boarding school in Dorset where he would find himself attracted to another able student, Christopher Morcom, who inspired young Alan to communicate more and pursue an academic path. Their intellectual companionship would leave a significant imprint on Turing after Morcom’s sudden death from tuberculosis, which inspired him to examine the problem of the mind and matter throughout his lifetime.

And it would around his undergraduate years at Cambridge when Turing realised that his attraction to men was a significant part of his identity, as he sought intimacy with an occasional lover, James Atkins, at the time a fellow mathematician. Only with years, he would become more outspoken about his sexual preference, leaving sexual conformity behind him. Curiously, when working at Bletchley Park, Turing had proposed to one of his female colleagues, Joan Clarke, who accepted the arrangement. However, Turing ended up retracting as he informed her of his true feelings.

On 31^{st }March 1952, Turing was arrested and trialled for sexual indecency after police learnt of Turing’s intimacy with a young man from Manchester. As a man who honoured the truth, Turing would not deny his “illegal acts”, but admitted to no wrong-doing. As a severe consequence, Turing chose to undergo the year-long hormonal treatment – which in essence was chemical castration, over a prison sentence. In the light of Turing’s “indecency”, his security clearance was revoked, ending his ongoing work with the government and leaving him as a man with highly classified information who had to endure intrusive police searches.

Turing was found dead of a cyanide poisoning in 1954, administered from an apple. The coroner’s verdict was suicide.

Throughout his life, not only did Turing display an exceptionally profound mathematical and logical reasoning, his curiosity of nature allowed him to establish links between seemingly unrelated topics to lay the first solid foundations of computer science. Without Turing’s contributions, it would have taken another prodigy and a questionable amount of time to pioneer the age of computing which has developed the strong human reliance on smart devices existing today.

Alan Turing was a man who has, and continues to transform the world- regardless of his sexual preference.