Alan Turing: A Brief Biography
No one person invented the computer, but the most important figure in the
development of computer science in the twentieth century was doubtless
Alan Matheson Turing. Turing was born in 1912 in London. His father
served in India, which at the time was a British colony. Alan, along with
his brother, John, was raised in English foster homes, far from his parents,
and attended the Sherbourne public school, where he was a mediocre student,
at best. The school reports of this budding genius tell of a boy whose
handwriting was terrible, who failed Latin and history, and who, most shocking
of all at the time, had no proper grounding in religion.
At Sherbourne, Turing became fast friends with Christopher Morcom, with
whom he shared a growing interest, unrecognized by his rigid teachers,
in mathematics and astronomy. Morcomís early death, in 1930, devastated
the young Turing, whose life had already been more than commonly devoid
of warmth and companionship. Morcomís death led Turing to speculate about
the possibility of survival after death and to wonder whether belief in
such survival was consistent with modern science, especially with the exciting
discoveries of the new physicsórelativity theory and quantum mechanics.
From 1931 to 1934, Turing studied at Kingís College, Cambridge, and
in 1935 he was elected a fellow of the college. After receiving the M.A.
degree from Kingís College and a Smithís prize for work in probability
theory, Turing published ìOn Computable Numbers,î
a paper that simultaneously explained what problems in mathematics were
computable and described a simple mechanism, logically analogous to modern
computers, capable of carrying out those computations. This so-called ìTuring
Machineî provides the theoretical basis for modern computer science. In
effect, Turing created on paper the concept of the modern computer, the
encoding of both instructions and data in a universal form, long before
computers were actually built.
After a stint at Princeton, in the United States, where he received
a Ph.D. in mathematical logic, Turing returned to England and to his fellowship
at Kingís College. The British government
soon drafted him to assist its effort to defeat Nazi Germany. The Nazis
were using a machine called the Enigma to encrypt secret wartime communications.
Turing headed a team of mathematicians who built a device called the Bombe
that could decipher messages encrypted by the Enigma machine, thus giving
the Allies access to critical battle plans and strategies. By breaking
the Enigma code, Turing helped make it possible for the United States to
seize control of the Atlantic from German U-2 boats, which in turn made
possible the Allied invasion of Europe.
When the war was over, Turing turned his attention to designing a real
electronic computer to embody his concept of a universal computing machine,
the Automated Computing Engine, or ACE. In those times, most people thought
of computers as machines for doing calculations, but Turing had grander
plans. Based on his belief that there is no substantive difference between
a computer and a human brain, both of which are calculating machines, Turing
imagined a machine equally at home doing mathematics, breaking codes, or
playing chess. His work on Abbreviated Code
Instructions for the Automated Computing Engine was one of the earliest
developments of a programming language. He also experimented with creating
computer systems that could learn, thus presaging modern neural nets. During
this time, Turing, who had long enjoyed long-distance running, became an
accomplished competitor in cross-country races. According to his biographer
Andrew Hodges, he would have been ìseriously consideredî for a spot on
the British team in the 1948 Olympics were it not for an untimely injury.
In 1950, Turing published in the journal Mind
a now-famous paper entitled ìComputing Machinery and Intelligence.î
In this paper, Turing proposed an experiment, commonly known as The Turing
Test, to settle the question of whether a computer can be considered intelligent.
In this experiment, a person placed in one room communicates with a computer
located in another room. Turing argued that if the person communicating
with the computer believes that he or she is actually communicating with
a human being, then the computer would have to be considered intelligent.
In 1990, Dr. Hugh Loebner established the Loebner prize, offering $100,000
to anyone who could write a program that could successfully pass The Turing
Test. Since then, the annual Loebner prize contest has stimulated the creation
of many fascinating programs that mimic human conversation, but no one
has yet claimed the $100,000 grand prize.
By any standard, Alan Turing was one of the most gifted persons in the
history of science or of mathematics. He laid the theoretical groundwork
for computing and helped the Allies win World War II by breaking the Enigma
code. He also made fundamental contributions to pure mathematics and to
the development of programming languages, neural nets, and artificial intelligence.
In the last years of his life, he turned his attention to the mathematical
study of morphogenesis, the science of the development of biological forms.
Sadly, this brilliant manís career was cut short.
In 1952, his home was burglarized by the friend of a male lover. Turing
reported the burglary to the police but then was himself arrested because
of his sexual orientation. Turing was tried for sodomy and publicly humiliated.
Because of his homosexuality, his security clearance was revoked, and he
was forced to undergo chemical castration by means of injections of the
female hormone estrogen. The man who had invented modern computing and
saved his country in wartime was found dead in 1954, an apparent suicide
by means of cyanide poisoning.
The story of the tragic end of Turingís life is told in Hugh Whitemoreís
play Breaking the Code, a film version of which, starring Derek
Jacobi and Harold Pinter, aired on United States television in February,
1997. There is also an excellent biography of Turing, Alan Turing: The
Enigma, by Andrew Hodges. |
