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Alan Turing

Life and Ethics

Paul I. Muntean

Matriculation number: 03620817

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Contents

Abstract 3

1. Chronology 4

2. Second World War and Bletchley Park 5

3. The “Cribs” 5

4. The Entscheidungsproblem 7

5. The Turing Machine 7

6. The Enigma Machine 8

7. The Imitation Game 9

8. The Mathematical Objection 10

9. Turing Test 11

10. Turing Life and Ethics 12

11. Conclusions 16

12. References 17

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Abstract

My paper on Alan Turing’s life and ethics will present a brief overview of one of the greatest

thinkers of our times.

The paper proposes to present Alan Turing from its youth until his death with all his

contributions to modern computer science.A lot of effort was invested during the last years in

puting together in different publications details about the life of Alan Turing and many

achievements were revealed. My paper will concentrate on the life of Alan Turing seen from an

ethical point of view and on the implications and further achievements in computer science

which had the basis laid by Alan Turing.

Alan Mathison Turing was one of the great pioneers of the computer field. He inspired the

now common terms of "The Turing Machine" and "Turing's Test." As a mathematician he

applied the concept of algorithm to digital computers. His research into the relationships

between machines and nature created the field of artificial intelligence. His intelligence and

foresight made him one of the first to step into the information age.

Alan Turing’s impact on today’s world has two main areas: first in the invention and

development of fundamental ideas which have enabled machines and programing to reach the

complexity from today and second to start debate on what constitutes intelligence, thinking and

understanding.

His work presents a deep mathematical analysis of all his subjects with which he was

concerned during his work and we can also observe his mathematical background in all his

work.

The paper will present the huge contributions of Alan Turing which he has made during his

time spent at Bletchley Park regarding what had to become modern computer science, software

design and artificial intelligence.

No deep details will be invested on the mathematical proofs since this is not the scope of this

paper but instead deep analysis will be made in the chapter which is concerning with his life and

ethics.

Turing had not a good treatment from the Authorities after he was declared gay; he was a

pioneer laying the basis for artificial intelligence and computer science. His work has deep

implications even in our times changing the face of the world by one of the greatest inventions of

the human kind: the computer.

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Chronology

We know Alan Turing as a pioneer in developing computer logic. He was the first to approach

the topic of artificial intelligence.

Born on the 23 June 1912 in London and he died on the 7 June 1954 in Manchester England.

He visits the Sherborne School, 1926-31; Wrangler, Mathematics Tripos, Kings College,

Cambridge, 1931; Ph.D., Princeton University, 1938 during his live time.

He is Fellow of King's College, 1935-45; Princeton University, 1936-38; British Foreign

Office, Bletchley Park, 1939-45; National Physical Laboratory, 1945-48; University of

Manchester, 1948-54;

The Smith’s Prize from Cambridge University in 1936 and the Order of the British Empire

(OBE) in 1946. He becomes Fellow of the Royal Society in 1951.

His aptitude for sciences became clear as soon as he began attending school. He was very

talented and showed great insight in mathematics and sciences, but was never interested in other

disciplines. Although his teachers tried to turn his attention to subjects like English or History as

well, he never felt passionate for anything else. This great attachment to science, visible from an

early age, remained with him for his entire life.

He pursued a deeper study of mathematics at King’s College, Cambridge University in 1931.

During the years spent there he showed little interest in using the work of previous scientists. He

approached all the problems by trying to recreate discoveries rather than imitating them, showing

revolutionary and original thinking. His aptitude earned him the privilege of becoming a fellow

of King's College upon graduation and he later on moved to the Princeton University. During

this time he worked on what would later on be known as the “Turing Machine”.

The Turing Machine is nowadays considered the predecessor of the concept of digital

computer. Multi-purpose computers can be compared as being a general concept of the Turing

Machine. He described a machine that would read a series of ones and zeros from a tape. These

ones and zeros described the steps that needed to be done to solve a particular problem or

perform a certain task. The Turing Machine would read each of the steps and perform them in

sequence, resulting in the proper answer.

Alan Turing was a pioneer in the field, and his idea revolutionized the 1950’s computer. The

Turing Machine, as opposed to the computers of that time that were specialized on a particular

field or a limited range of purposes, was created having in mind the concept of a computer that

can do anything. A very important part in this concept held the method used for instructing the

machine. He essentially described a machine which knew a few simple instructions. Making the

computer perform a particular task was simply a matter of breaking the job down into a series of

these simple instructions.

This is identical to the process programmers go through today. He believed that an algorithm

could be developed for almost any problem. The hard part was determining what the simple steps

were and how to break down the larger problems.

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Second World War and Bletchley Park

During the troubled times of World War II, Turing’s intellectual power and mathematical

skills attracted attention on him. This lead to his implication in espionage issues during the war,

directed by the Department of Communications. Turing had been identified, at Cambridge, as

likely candidate for code breaking because his deep knowledge in mathematics. He came to

Government Code and Cypher School (GC&CS) in Broadway in London a number of times in

early 1938 to show what he had already been achieved. He was shown some intercepts of

German signals enciphered on the German forces Enigma cipher machine. With his

mathematical skills he managed to achieve the difficult task of deciphering the codes the

Germans were using to communicate.

The principle of the Enigma machine can be assimilated as an electro/mechanical way of

achieving a seven or nine layer substitution cipher. Wirings inside the machine were determining

the substitutions. Wheels which could be rotated by the operator but which also index round, like

a car miles indicator, as letters to be enciphered or deciphered were entered. It was able to

generate a constantly changing code that was impossible for the code breakers to decipher in due

time.

The original patent of the Enigma machine was released in 1918 by Arthur Scherbius in

Berlin, developed by him as a commercial product and shown to the public in 1922. Because the

machine could be bought by anyone, the security of the cipher depended not on the machine

itself but on the vast number of ways in which it could be configured before the start of an

encryption. In order to make this setting up more complicated each wheel had a tire or ring

around the core containing the cross wiring. Letters or numbers on the surface of this ring

appeared in the windows above each wheel. The ring could be rotated around the core and set by

the operator before the encryption began. It remained set throughout the message input.

The action of pressing a key caused the right hand wheel to index one position. At some point

this rotation was transferred to the next wheel on the left. This is known as a carry and is caused

by a slot, the carry slot, coming into line with the indexing pawls. This carry slot was initially on

the wheels and later it was moved to the ring.

From 1930 the plug board “Stecker” was added to the Enigma used by the German Army and

Air Force. The plug board enabled pairs of letters to be completely transposed. Initially 6 pairs

were transposed, later this was increased to 10, the nearly optimum number. At the same time the

reflector became fixed. This machine was then also adopted by the German Navy. For this

Enigma the wheels give 6 x 26 x 26 x 26 = 105,456 possible combinations. Six plug pairs give

100,391,791,500 possibilities; total approximately ten thousand, million, and million.

The Polish Security service had purchased a commercial Enigma and worked out in 1920’s

methods for breaking it. All the Polish achievements were divulged to the British and the French

at the famous meet in the Pyry Forest near Warsaw in July 1939. In September 1939 Turing

came to Bletchley Park and joined Dilly Knox in the cottage in the stable yard. He started to

think of ways to break Enigma using probable words “cribs” and was intrigued by the problems

in breaking the German Naval Enigma.

GC&CS already had a few intercepts and at least one plain text/cipher text pair which were

reputed as being smuggled to England by a Polish cipher clerk.

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The “Cribs”

One of the remarkable characteristics that Turing found in the messages used for deciphering

was that occasionally the same cipher/plain text pair of letters occurred at different places in the

same message.

JYCQRPWYDEMCJMRSR

SPRUCHNUMMERXEINS

Fig.1. Crib example.

This can happen since the Enigma machine is reversible: R-C is the same as C-R and M-E the

same as E-M. Such pairings occurrences are determined by the rotor order and the starting

positions of the core rotor. These results were independent of the configuration of the Steckers

board.

An extension of the concept of letter pairs is where letters enciphered from one to another at

different places in the crib resulting in loops of letters. In 1939 Turing has proposed a letter

frequency attack using what he called the “E” rack. There are no surviving documents to give

details about this idea. Virtual E rack shows that it would have been feasible and an

improvement of the deciphering process could be plausible.

The Letter frequency observed in the ciphered test claims that natural frequency of letters in

normal text is far for being random. For example in German and in English the letter E occurs

12% compared with the random score of 4%. Turing observed that this process of determining

the frequency can be mechanized in the process of developing of the Turing Bombe.

Once messages began to be deciphered, it was realized that the German word EINS was by

far the most frequent word in naval messages.

Problems were faced in working with the so called bigram tables. In order to decipher all

messages during a day it was necessary to recover the entire daily key. The Wheel order and

Wheel start were needed for deciphering the message key ( “Grund” and the “Steckers”).

In 1940 the breakthrough came when a trawler intercepted on April 26 a destroyer named

Arrow. The crew had thrown overboard two bags containing the Stecker and Grundstellung for

the day 23 and 24 of April. The data gathered from this capture confirmed Turing assumptions.

On April 1941 – February 1942 a major capture of February ’41 keys allowed the bigram table to

be completely built up.

Cribs obtained from Admiral Doenitz messages were of high importance since they helped to

push the process of deciphering even further. As a reaction also the Bombe was changed in order

to fit the new requirements of the 4 wheeled Enigma machine. The forth wheel was a high

revolution wheels which was connected to the old system with a thick cable known as “Cobra”.

After Turing worked for deciphering the Enigma code he orients his attention to the Lorenz

teleprinter cipher system. Turing devised a statistical method for helping to get out wheel

patterns, known as “Turingismus”. This was replaced when the Colossi became available.

At the end of 1943 Alan Turing work on code breaking in Bletchley Park had come to end

and he moves to nearby Hanslope Park to work on his ideas for a speech enciphering system that

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he called “Delilah”. Together with Don Bayley he started to build the Delilah and in the May of

1945 it was completed.

For understanding the huge contribution of Turing that he had during his stay at Bletchley

Park it is recommended to read the History of Naval Enigma by Hugh Alexander.

H. Alexander claims in his book that Turing had one of the highest implications in the events

at Bletchley Park. During the Hut 8 project Turing he collaborated a lot with Welchman and

Keen which has the chief credit for the invention of the electro/mechanical device named

Bombe. The pioneer work tends to become forgotten after a while when routine appears and

everything appears to be easy.

The Entscheidungsproblem

The Entsceidungsproblem asks whether there exists a “decision algorithm” such that:

As an input we have two: a finite set of axioms, and a conjecture

It computes for a finite time and outputs either a proof of the conjecture from the

axioms, or “no proof exits”.

The result is always correct.

Turing is renowned for his negative solution to the Entscheidungsproblem. Apparently Hilbert

hoped for a positive solution for the problem. A negative solution has to prove that there is no

algorithm that could do the job and have to have a definition of the “algorithm”.

The question “What is an algorithm?” is answered by Turing in 1936 by denying Turing

machines. He used his definition to prove that there exists a problem that cannot be solved by

any algorithm. The most well-known of these is the “halting problem”.

In order to proof the negative solution for the Entscheidungsproblem Turing applies his

Turing machines. His solutions use the fact that the halting problem is not solvable by a Turing

machine.

The solution found by Turing can be synthetized in three steps:

Write axioms to describe the computations of Turing machines.

Turing machine M halts at input x if and only if the axiom proves the theorem “M

halts at input x”.

If we had an algorithm to determine the consequences of axioms A, it would solve the

halting problem, contradiction. Hence no such algorithm exits.

The Turing Machine

In his 1936 paper Turing describes the concept which explains his machines which now have

his name. A finite state machine controlling a mobile head, which operates on a tape, is the

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simple definition of a Turing machine. The tape composed of a sequence of locations represented

by rectangles in the following figure which contains a string of symbols constituting the data.

The tape should be considered theoretically infinite in both directions.

Fig.2. A specialized Turing machine represents the reading head

The set of operations performed by the machine:

1. Reading the symbol stored in the accessed location on the tape;

2. Writing a symbol in the accessed location, erasing the previous symbol

3. Deplaning the head left or right to an adjacent location (which becomes the accessed

location for the next computation step).

A Turing machine is described by the functions.

Q+ = (Q, S)

Eq. 1

S+ = (Q, S)

Eq. 2

D+ = (Q, S)

Eq. 3

Where Q and S represent the current internal state of the finite state machine and the current

input symbols Q+, S+, D+ are the next internal state of the finite state machine.

As a result we can represent a Turing Machine as a quintuple having the form.

(Q, S, Q+, S+, D+)

Eq. 4

The Enigma Machine

Fig.3. The Enigma Machine

The German Enigma is best known for his decisive role in the

events of the Second World War. Invented in 1918, it was developed

as both a commercial and military encryption system before and

during the war. Enigma is an electro-mechanical device that utilizes

a stepping wheel system to “scramble” a plaintext message to

produce cipher text via polyalphabetic substitution. Potentially, the

number of cipher text alphabets is astronomically large. This fact led

the German military authorities to believe, wrongly as it turned out,

in the impossibility of cracking the enciphered code.

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A Polyalphabetic substitution cipher text is obtained at the output of the Enigma machine. It

has a 3-wheel system and several other components. A message to be enciphered is input from a

keyboard - QWERTZUIO layout. The signal leaves the keyboard and passes through a plug

board where, if the plug board socket contains a connector, its identity is switched in a mono-

alphabetic substitution. The socket can be without a plug. The identity of the input character is

unchanged. The plug board substitution is reciprocal - i.e. if A is switched to Z, then Z is

switched to A, a weakness that was to be exploited by Allied cryptanalysts.

After passing the plug board the signal then passes to the entry stator which passes it to the

first of a series of three wheels. Each of these has twenty-six contacts on each of its faces, cross-

wired in a random fashion so that the identity of an incoming character is changed three times as

it passes through the three wheels, which are in electrical contact, each with its adjacent

companion. After each keyboard pressing the extreme right-hand wheel moves one position -

before encryption takes place. Additionally, once during a complete revolution of each wheel,

the wheel to its left steps once.

After passing through all three wheels the signal reaches the reflector which performs two

functions - it changes the signal's identity once again and also sends it back, in the reverse

direction, through the three wheels to the entry stator. From here it passes back to the plug board

and then to the lamp board where a lamp corresponding to the now enciphered character is

illuminated.

The reflector's function in the encryption process has as result that no plaintext character can

ever encipher to itself. This weakness in the system was exploited to great effect by the Allied

cryptanalysts.

Parameters like the following could be adjusted in order to set up the machine so that the

result could vary.

Walzenlage: A subsystem composed of wheels can be selected from a set of five in the case of

the Army and Air Force machines and from a set of eight in the case of the naval machines. The

daily would also specify the reflector [Umkehrwalze] and, in the case of the Kriegmarine's M4,

the selection of the fourth, “Greek”, wheel and its “thin” reflector.

Ringstellung: After setting the index ring on each, the three wheels were arranged on the

machine's spindle in the order prescribed in the daily [or other periodic] instructions for machine

initialization.

Steckers: The plug board was set up according to the same instructions. Normally ten sets of

plugs were used leaving six letters “self-steckered”.

The internal lid of the Enigma was closed and the wheels set to the initial position and the

machine was ready to be used.

The imitation game

The fundamental question associated with Turing is: "Can machines think?" For a better

understanding we should begin with definitions of the meaning of the terms "machine" and

"think". The definitions might be framed so as to reflect so far as possible the normal use of the

words but this attitude is dangerous. If the meaning of the words "machine" and "think" are to be

found by examining how they are commonly used it is difficult to escape the conclusion that the

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meaning and the answer to the question, "Can machines think?" is to be sought in a statistical

survey such as a Gallup poll. But this is absurd. Instead of attempting such a definition I shall

replace the question by another, which is closely related to it and is expressed in relatively

unambiguous words.

The question can be put also like this: “Have machines the same sort of intelligence as

humans do?”

The game called “imitation game” is used to describe the new form of the problem. It is

played with three people, a man (A), a woman (B), and an interrogator (C) who may be of either

sex. The interrogator stays in a room apart from the other two. The object of the game for the

interrogator is to determine which of the other two the man is and which the woman is. He

knows them by labels X and Y, and at the end of the game he says either "X is A and Y is B" or

"X is B and Y is A." The interrogator is allowed to put questions to A and B thus:

C: Will “X” please tell me your profession?

Suppose X is actually A, then A must answer. It is A's object in the game to try and cause C

to make the wrong identification. His answer might therefore be:

"My profession is dentist and I like to play tennis in my free time."

An ideal arrangement is to have a teleprinter communicating between the two rooms.

Alternatively the question and answers can be repeated by an intermediary. The object of the

game for the third player (B) is to help the interrogator. The best strategy for her is probably to

give truthful answers. She can add such things as "I am the woman, don't listen to him!" to her

answers, but it will avail nothing as the man can make similar remarks.

What if now, "What will happen when a machine takes the part of A in this game?" Will the

interrogator decide wrongly as often when the game is played like this as he does when the game

is played between a man and a woman? These questions replace our original, "Can machines

think in a similar manner in which human think?"

The Mathematical Objection

Mathematical logic provides until now a lot of examples which can be used to show that there

are limitations to the powers of discrete-state machines. The best known of these results is

known as Godel's theorem ( 1931 ) and shows that in any sufficiently powerful logical system

statements can be formulated which can neither be proved nor disproved within the system,

unless possibly the system itself is inconsistent. There is other, in some respects similar, results

due to Church (1936), Kleene (1935), Rosser, and Turing (1937).

The most convenient is to consider the later result, since it refers directly to machines,

whereas the others can only be used in a comparatively indirect argument: for instance if Godel's

theorem is to be used we need in addition to have some means of describing logical systems in

terms of machines, and machines in terms of logical systems.

The result in question refers to a type of machine which is essentially a digital computer with

an infinite capacity. It states that there are certain things that such a machine cannot do. If it is

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rigged up to give answers to questions as in the imitation game, there will be some questions to

which it will either give a wrong answer, or fail to give an answer at all however much time is

allowed for a reply.

Out there, there are a large number of such questions and questions which cannot be

answered by one machine may be satisfactorily answered by another. We are of course

supposing for the present that the questions are of the kind to which an answer "Yes" or "No" is

appropriate, rather than questions such as "What do you think of Picasso?" The questions that we

know the machines must fail on are of this type, "Consider the machine specified as follows. . . .

Will this machine ever answer 'Yes' to any question?" The dots are to be replaced by a

description of some machine in a standard form.

If between the described machine is a comparatively simple relation to the machine which is

under interrogation, it can be shown that the answer is either wrong or not forthcoming. This is

the mathematical result: it is argued that it proves a disability of machines to which the human

intellect is not subject.

The answer is that although it is established that there are limitations to the Powers If any

particular machine, it has only been stated, without any sort of proof that no such limitations

apply to the human intellect. But I do not think this view can be dismissed quite so lightly.

Whenever one of these machines is asked the appropriate critical question, and gives a definite

answer, we know that this answer must be wrong, and this gives us a certain feeling of

superiority.

Is this feeling illusory? It is no doubt quite genuine, but I do not think too much importance

should be attached to it.

As humans we also give from answers to questions that could be justified in being very

pleased at such evidence of fallibility on the part of the machines. Further, our superiority can

only be felt on such an occasion in relation to the one machine over which we have scored our

petty triumph. There would be no question of triumphing simultaneously over all machines. In

short, then, there might be men cleverer than any given machine, but then again there might be

other machines cleverer again, and so on.

Those who hold to the mathematical argument would, I think, mostly he willing to accept the

imitation game as a basis for discussion, those who believe in the two previous objections would

probably not be interested in any criteria.

Turing Test

In order to find out if a system is intelligent we use the Turing Test. It was originally proposed

by mathematician Alan Turing, one of the founding figures in computing. Turing argued in a

1950 paper that conversation was the key to judging intelligence. In the Turing test, a judge has

conversations via a teleprinter with two systems, one human, the other a machine. The

conversations can be about anything, and proceed for a set period of time e.g., an hour. If, at the

end of this time, the judge cannot distinguish the machine from the human on the basis of the

conversation, then Turing argued that we would have to say that the machine was intelligent.

A number of opinions are expressed about the Turing test in cognitive science. Some

researchers argue that it is the benchmark test of what Searle calls strong AI, and as a result is

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crucial to defining intelligence. Other researchers take the position that the Turing test is too

weak to be useful in this way, because many different systems can generate correct behaviors for

incorrect (i.e., unintelligent) reasons. Famous examples of this are Weizenbaum's ELIZA

program and Colby's PARRY program. Indeed, the general acceptance of ELIZA as being

"intelligent" so appalled Weizenbaum that he withdrew from mainstream AI research, which he

attacked in his landmark 1976 book.

Turing Life and Ethics

Alan Turing’s life marked the course of twentieth-century history and can be naturally divided

into pre-war, wartime and post-war periods. Born into the British upper-middle class which had

confidently run the imperial administration until the First World War, but which, under the

impact of economic and political crisis, progressively lost control thereafter. In a very broad

sense, Alan Turing belonged to a new, modernizing generation, which reacted contemptuously

against Victorian values. But Alan Turing's early life was marked by detachment from the

obligatory social training, rather than rebellion against it. It was also marked from the start by his

intensely individual response to science and mathematics, in particular to the relativity and

quantum mechanics, which had transformed the physical sciences since 1900. He became an

undergraduate at King's College, Cambridge University, in 1931, reading Mathematics and

graduating with distinction in 1934.

Through the lectures of M. H. A. (Max) Newman at Cambridge, young Turing was introduced

to the frontier of mathematical logic, which also had been transformed since 1900. But logic was

neither Turing's immediate nor his only choice. It was his work in probability theory that won

him a Fellowship of King's College in 1935, and he might easily have continued in this field, or

else in the mathematical physics that had first attracted him. Thus he came to logic from a wide

background in pure and applied mathematics, and it was in this eclectic spirit that he attacked the

Entscheidungsproblem of David Hilbert, which at that point remained an outstanding question.

Turing, working alone, and only twenty-three, attacked and settled this problem by his definition

of computability. His famous paper, On Computable Numbers, with an application to the

Entscheidungsproblem, was published at the turn of 1936-37. A complete outsider to the field, he

won a place in the subject with a concept which after sixty years remains definitive. His

definition of computability showed there could be no general method for deciding the provability

of mathematical propositions, and marked the end of attempts to formalize a complete system for

mathematics. The way into new fields was opened, which now we would recognize as computer

science and the cognitive sciences.

Turing is categorized as a logician but he was more a mathematician who applied himself to

logic. The interest of Turing for the human mind appeared in his statements about human

memory and states of mind which informed his arguments. His background in physics was

hinted at in the “machines” with which he made his definition of computability, the now-famous

“Turing Machines”, running on paper tape, an image of 1930’s modernity. It was this

concreteness which made Turing's definition of computability much more satisfactory than the

mathematical definition offered by Alonzo Church, the Princeton logician who led the field.

Mathematically, Turing's definition was equivalent to Church's. But the description of the Turing

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machine gave a convincing argument for why it was that this mathematical definition completely

captured the concept of “effectively calculable”.

A Turing machine can be considered an algorithm, for modern readers it is hard not to see it

as a computer program and to bear in mind that computers did not then exist. But Turing

specifically defined a type of machine called “universal”, capable of reading the instruction table

of any other machine. We obtain the basic idea behind the concept of stored-program in a digital

computer.

Many scientists claim that Turing also imagined a computing machine similar to present-day

computers. He was certainly interested in electric and mechanical computation but whether he

really designed or built such a machine remains unanswered because there is no real evidence

suggesting this. Rather, he was primarily engaged in a wide variety of mathematical researches.

After joining Church’s group at Princeton in late 1936, he then embarked on more advanced

logic but also on work in algebra and in developing the theory of the Riemann zeta-function,

fundamental to the study of prime numbers. After turning down a post at Princeton offered by

the mathematician Jon von Neumann who hoped that promising young man would continue his

research in mathematics, Turing chose to return to England in summer 1938, conscious of the

impending conflict with Germany and already prepared to make a special contribution to it.

During Second World War many of his scientific contemporaries went into the physics of radar

and the atomic bomb, Alan Turing followed the direction of cryptology. After 1938, his

grappling with the infinitudes of mathematical logic was complemented by the finite but still

highly challenging logical problem of the German Enigma enciphering machine. In 1939

together with the help of the polish scientists who started also their work on encoding the

Enigma Turing was able to present a solution to the encipherement process of the Enigma. His

logical scheme was rapidly materialized in very large electromechanical devices called Bombes,

which from 1940 onwards worked as the central engines of decipherment throughout the war.

For this work, Turing was based at the now famous center at Bletchley Park, Buckinghamshire,

which recruited increasingly large sectors of the British intelligence. Amongst these, Alan Turing

remained the chief scientific figure. His central contribution, after the logic of the Bombe, laid in

Bayesian statistics for measuring “weight of evidence”, a development close to Shannon's theory

of information measure.

Turing started a scientific revolution, and because he took personal charge of the crucial U-

boat message problem, was able to see his approach triumph in the battle of the Atlantic.

Turing’s role was influenced by the course of the war: at first a lone British figure against all the

odds, and later, as the work developed on a major industrial and transnational scale, handing over

the British contribution to the power by which it was eclipsed: the US.

Outside the environment of Cambridge the personality of Turing is revealed as being a shy

but outspoken, nervous but lacking deference. He was not well adapted to military manners or to

the diplomacy of the embryonic Anglo-American relationship. But his commanding scientific

authority made him the top-level technical liaison between the wartime Allies, demanding a

voyage to America in the winter of 1942-43 at the height of the Atlantic battle. None of this

experience, however, gave him a taste for power or detracted from his primary vocation as a pure

scientist. After 1943 Turing was able to predict that a large scale of computers can be fabricated

by following the schemas used in his 'universal machine.' From now on his primary strive was to

become able to build such a machine, and he arranged his work so as to gain personal experience

of electronic components designing and building an advanced speech scrambler. He had a plan

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for an electronic computer, but it was motivated not by military or economic needs. It was for the

exploration of the scope of the computable and in particular for comparing machine processes

with human mental processes. He called it “building a brain”.

As a reward for his war time efforts Turing was honored with the modest British formality of

an OBE. His work remained hidden to the public until 1975, and he derived no advantage from it

in his subsequent scientific career. Nevertheless, the post-war period began with great promise,

for he was invited to take up an appointment at the National Physical Laboratory, near London,

in October 1945, and his electronic computer plan, the proposal for the Automatic Computing

Engine (ACE), was swiftly adopted in March 1946.

Turing used the term Practical Universal Computing Machine which later on would become

the word “computer”. But although fond of the word 'practical', Turing did not have the human

gift of getting his practical way with people and institutions who did not share his vision. From

the outset, it became clear that the NPL had no clear idea on how it was to build the machine he

had designed, and it failed to adopt a policy speedy enough to satisfy Alan Turing. Turing's plans

for software, exploiting the universality of the machine, were the strongest feature of his

proposal, but they were little developed or publicized because of the dominating problem of

hardware engineering.

The problem was attached by first creating the electronically devices. In order to release the

stress Turing had rune the marathon almost as Olympic standards. In 1947 he returned to

Cambridge and during this time he was approach by Max Newman who was a mathematics

professor there and he proposed to him to take there an appointment.

At Bletchley Park the scientist Newman played an important role and after 1942 he had

organized a section using the most sophisticated electronic machinery. He was also fully

acquainted with Turing's logical ideas. In Manchester he rapidly recruited the best engineers, and

by June 1948 a tiny version of the universal machine principle was working there. Turing

accepted the appointment as Deputy Director of the Computing Laboratory. But already in 1948

it became clear that the engineering would dominate the Manchester environment, and before

long both Newman and Turing were sidelined and did not direct anything at all.

The programming of Turing never exploited the advanced possibilities he had mapped out in

1946, and he failed also to write the papers that could have established his claim to the theory

and practice of modern computing. Instead, the main theme of his work became the more

futuristic prospect of Artificial Intelligence, or “intelligent machinerry” as he called it. Already

prefigured in 1946, this was expounded in papers of 1947, 1948, and 1950, arguing strongly that

computable operations could encompass far more than those things considered 'merely

mechanical' in common parlance, and indeed could emulate human intelligence. The last of these

papers, the only one to be published in his lifetime, appearing in the philosophical journal Mind,

has become famous for the Turing Test and its fifty-year prophecy, and stands still as a flagship

for confidence in the ultimate mechanizability of Mind. The long term vision about how

Artificial Intelligence can be achieved is as important as the thoughts that Alan Turing had

presented in his paper. Turing’s ideas contained the top down and the bottom up ideas that were

to become bitter rivals in later AI research. But it is also notable that he did very little to follow

up these ideas with active research, even when he had the resources of the Manchester computer.

In 1951 Turing was elected to a Fellowship of the Royal Society, the citation referring to his

1936 work. This was a watershed year for Turing: although he had largely failed in the

15

immediate post-war period to capitalize on his wartime achievement, he now started a quite fresh

development, demonstrating the part he could still have in the great expansion of science and

mathematics that began in the 1950s.

He wanted a mathematical explanation for morphogenetic phenomena, thus showing an

interest in biology that went back to childhood, but which was now expressed in advanced

methods for studying non-linear partial differential equations with the computer simulations

which had just become possible on the Manchester computer.

In the last months of 1951 Turing submitted a first paper on this work, which for

mathematical biology was to be as important as his 1936 work had been for logic. After this

moment Turing was arrested and put on trial. As a homosexual, he was always in danger from

the law which at that time criminalized all homosexual activity. After the trial in March 1952 he

was subjected to estrogen injections. He fought hard to prevent this from arresting his work.

Turing found himself rapidly as being isolated in Manchester at that time. In 1953 there was

another “crisis” with the police, which may well have been related to the fact that as a known

homosexual he fell into the new category of “security risk”, one who could no longer continue

the secret work he had previously been doing. His holidays abroad to less hostile climes would

not have calmed the nerves of security officers.

Turing had found time not only for morphogenetic theory but also for quantum mechanics

which had interested him from his youth on. His work had an abrupt ending in 1954 when he

poisoned himself with cyanide. The suicide was made like this to leave space for those who

wanted to believe that it was an accident.

An eccentric person which delighted yet often infuriated his friends. Alan Turing was

wrapped up in world events and yet most concerned with an intense personal integrity. He was

able to write almost as he was talking. His large capacity for frivolity, as illustrated in his

discussion of the Turing Test setting, gave him an honorable place in the lighter and cheekier

side of English culture.

The life of Turing is a paradox regarding his homosexual orientation and the thing that he said

that the human mind is something completely mechanic. The biggest contribution was his

application to war work which was of greater effect than perhaps any other individual scientist.

Because of his sexual orientation and because his work done during World War Two his life is

shadowed in secrecy even he dedicated to openness and honesty.

The drama behind his death has given Turing a lasting life in public consciousness. His state

of mind at death remains an enigma, but so too does the true inner story of his life. Prickly and

proud, yet self-effacing, Turing wrote little about the development of his ideas. There is the

unknown background to his fascination with the problem of Mind.

Only juvenile fragments survive of this work. There is the question raised by Newman, of

whether he might have done greater things in mathematics rather than for the war. He raises the

question of the real motivations for Turing's abandonment of deep mathematical work for the

sake of the war. The vexed question of the emergence of the digital computer in 1945, and of

Turing's relationship with von Neumann, remains a gap at the heart of twentieth-century

technology. The true genesis of his Artificial Intelligence during the war, and the question of

whether his concern for the significance of Gödel's theorem was really resolved remain unclear.

Even with our spur to twenty-first century thought and our fascination with the theory and

practice of intelligent life.

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In June 8 1954 his cleaner finds Turing death. He had died the previous day. A post-

mortem examination established that the cause of death was cyanide poisoning. When his body

was discovered an apple lay half-eaten beside his bed, and although the apple was not tested for

cyanide, it is speculated that this was the means by which a fatal dose was delivered.

An inquest determined that he had committed suicide, and he was cremated at Working

Crematorium on 12 June 1954. A fan of the theory that his death was an accidental was his

mother. She claimed his death was caused by her son's careless storage of laboratory chemicals.

Biographer Andrew H. suggests that Turing may have killed himself in an ambiguous way quite

deliberately so that his mother can think that it was an accident. David Leavitt has suggested that

Turing was re-enacting a scene from the 1937 film Snow White, his favorite fairy tale, pointing

out that he took "an especially keen pleasure in the scene where the Wicked Witch immerses her

apple in the poisonous brew."

Conclusions

Alan Turing discovered early on the interest for mathematics and this since wanting to explain

itself how things functions by using mathematics as a tool.

His methods of investigation in the field of deciphering encrypted messages show a high level of

passion. He was driven in his work by the fact that being able to decipher this encoded messages

England could have a big advantage in the warfare of the Second World War

One can observe that his ideas have a philosophical connotation like for example his basic

question that he had address to the public: Can machines think? We can observe that Turing was

not only interested in pure mathematics but also in the mystic and religious aspects of life.

He was considered as being an eccentric figure he contributed a lot in the efforts of deciphering

the Enigma code. The reader can address itself the question: What if the laws in that days were

not so restrictive. What would his contributions to humanity really be?

Changing the course of the Second World War as one of his great contribution to humanity

helped to save on both sides a couple of millions lives.

My opinion regarding Turing death is that he was pushed by the authorities and by his inability

to reconcile his scientific work with his personal life. He was not able to find the balance

between his emotional part and his exterior appearance. Probably if homosexual couples were

legal back in that days it would be not so hard for him to live his life further and to not come to

the chosen solution of suicide.

Nevertheless as people living and using the inventions and tools of the 21 century we have to

think with great respect at the address of Turing and to remember that each new path starts with

the first step and each new concept with the first concrete idea. Turing is the person who brought

the stone to role and open the way to a wonderful future for human kind.

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References:

Andrew Hodges,1989, Kammerer & Unverzagt, Alan Turing, Enigma

John Prager. 2001. On Turing, ISBN: 0-534-58364-4.

Colby, K.M. et al. (1972) Artificial paranoia. Artificial Intelligence, 2, 1-26.

Colby, K.M. et al. (1973) Turing-like undistinguishability tests for the validation of

a computer simulation of paranoid processes. Artificial Intelligence, 3, 47-51.

Turing, A.M. (1950). Computing machinery and intelligence. Mind, 59, 433-560. Weizenbaum,

J. (1976). Computer power and human reason. San Francisco, CA: W.H. Freeman.