A Father of Computer Science and AI:
One of the most brilliant and influential minds of twentieth century, Alan Turing was a British mathematician and logician, a father of computer science and artificial intelligence, who also served as cryptanalyst during World War II and for some time afterwards. His life was anything but ordinary. Though his affiliation was never with philosophy departments, some of his work – most notably the 1950 article "Computing Machinery and Intelligence" – has inspired lively debates in philosophy of mind and logic.
Computability:
At age twenty-four, Turing published his first academic article, "On Computable Numbers, With an Application to the Entscheidungsproblem" (1936-1937). The article is nowadays regarded as the place where the contemporary concept of computability is introduced and, thus, a founding stone of computer science.
Briefly, Turing’s idea was to reformulate Kurt Gödel’s 1931 incompleteness theorems (one of the highest achievements of modern logic) in non-arithmetical terms. Turing proved that a machine can compute any calculation provided that an algorithm to carry it on is available; on the other hand, if no algorithm is available, then the machine would never reach an end to its search for a result.
Undercover Cryptanalyst:
Turing reported to Bletchley Park (the headquarter of British cryptanalysis) as WWII exploded in September 1939; there he joined a group of talented minds whose main goal was to break the code of the German enciphering machine Enigma. Within a few weeks from his involvement, Turing had made some decisive contribution to the development of so-called Turing-Welchman bombe, an electromechanical machine vastly more efficient than any other one available to search for possible correct readings of an Enigma enciphered piece of code.
Turing’s work at Bletchley Park can hardly be underestimated. Nicknamed as "Prof," he soon was recognized as a leader for his brilliant ideas; two of the papers he produced during this period, "Report on the Applications of Probability to Cryptography" and "Papers on Statistics of Repetition," were so precious to the School that they were not released to the UK National Archives until April 2012.
The Turing Test:
Turing is most famous for having put forward a kind of behavioral test for the presence of mind or thought, called the Turing Test. Suppose you are told that you have to interrogate in writing both a machine and a person, who are placed in a room other than yours (so you do not see them); your job is to sort out which is the machine and which is the person. You will address your questions to one agent at a time, referring to the agents as X and Y. So, for instance, you will ask: "Will X please tell me whether X plays chess?" If you are not able to determine which is the person and which the machine, then that would be the proof that machines are thinking.
To date, no computer has ever passed the test. Turing was convinced that within half a century we would have been able to create machines so powerful to pass this test, thus defying Descartes’s conjecture that mind and body are altogether heterogeneous. Evidently, he was counting on his genial contribution!
Morphogenesis:
Starting from 1948, Turing was appointed as Reader in the Mathematics Department at the University of Manchester. Here, in the latter part of his life, he turned his attention to mathematical issues applied to biology, in particular to morphogenesis: how is it that single cells can create analogous patterns within plants and animals, such as those we observe on the wings of a butterfly, the skin of a leopard, or in the distribution of seeds in a sunflower. Turing used – and improved – reaction-diffusion equations to find an answer to such questions, providing a seminal contribution to the field.
Further Sources:
One of the most brilliant and influential minds of twentieth century, Alan Turing was a British mathematician and logician, a father of computer science and artificial intelligence, who also served as cryptanalyst during World War II and for some time afterwards. His life was anything but ordinary. Though his affiliation was never with philosophy departments, some of his work – most notably the 1950 article "Computing Machinery and Intelligence" – has inspired lively debates in philosophy of mind and logic.
Computability:
At age twenty-four, Turing published his first academic article, "On Computable Numbers, With an Application to the Entscheidungsproblem" (1936-1937). The article is nowadays regarded as the place where the contemporary concept of computability is introduced and, thus, a founding stone of computer science.
Briefly, Turing’s idea was to reformulate Kurt Gödel’s 1931 incompleteness theorems (one of the highest achievements of modern logic) in non-arithmetical terms. Turing proved that a machine can compute any calculation provided that an algorithm to carry it on is available; on the other hand, if no algorithm is available, then the machine would never reach an end to its search for a result.
Undercover Cryptanalyst:
Turing reported to Bletchley Park (the headquarter of British cryptanalysis) as WWII exploded in September 1939; there he joined a group of talented minds whose main goal was to break the code of the German enciphering machine Enigma. Within a few weeks from his involvement, Turing had made some decisive contribution to the development of so-called Turing-Welchman bombe, an electromechanical machine vastly more efficient than any other one available to search for possible correct readings of an Enigma enciphered piece of code.
Turing’s work at Bletchley Park can hardly be underestimated. Nicknamed as "Prof," he soon was recognized as a leader for his brilliant ideas; two of the papers he produced during this period, "Report on the Applications of Probability to Cryptography" and "Papers on Statistics of Repetition," were so precious to the School that they were not released to the UK National Archives until April 2012.
The Turing Test:
Turing is most famous for having put forward a kind of behavioral test for the presence of mind or thought, called the Turing Test. Suppose you are told that you have to interrogate in writing both a machine and a person, who are placed in a room other than yours (so you do not see them); your job is to sort out which is the machine and which is the person. You will address your questions to one agent at a time, referring to the agents as X and Y. So, for instance, you will ask: "Will X please tell me whether X plays chess?" If you are not able to determine which is the person and which the machine, then that would be the proof that machines are thinking.
To date, no computer has ever passed the test. Turing was convinced that within half a century we would have been able to create machines so powerful to pass this test, thus defying Descartes’s conjecture that mind and body are altogether heterogeneous. Evidently, he was counting on his genial contribution!
Morphogenesis:
Starting from 1948, Turing was appointed as Reader in the Mathematics Department at the University of Manchester. Here, in the latter part of his life, he turned his attention to mathematical issues applied to biology, in particular to morphogenesis: how is it that single cells can create analogous patterns within plants and animals, such as those we observe on the wings of a butterfly, the skin of a leopard, or in the distribution of seeds in a sunflower. Turing used – and improved – reaction-diffusion equations to find an answer to such questions, providing a seminal contribution to the field.
Further Sources:
- The entry on Turing’s Test at the Stanford Encyclopedia of Philosophy.
- Turing’s Archive, a website containing plenty of useful biographical and academic resources.
- The Alan Turing Home Page, maintained by Andrew Hodges, containing a wealth of information.
- The Turing Archive for the History of Computing, a unique archive collecting documents forming the history of computing.
Source...