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Turing Test

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Hainsch, David (21. Nov 2018, within the course "Odyssey of Philosophy and Information", facilitated by J.M.Díaz at HM)

(1) The comments of the facilitator will be edited using this style, brackets, 8 pt, color change. These will be introduced in between your own text to discuss and further co-elaborate the content. Whenever the authors consider to have addressed the issue, they can simply remove the comment
(2) Simple corrections, corresponding to quite obvious missteps or disalignment with editorial style guidelines, are directly corrected, marking the involved characters in red in order to let the author know what was changed. The authors can turn it into black if they agree upon] 

(i) You have done a good job referring the Turing test and its connection to other articles in the glossariumBITri. As I said in the AI entry you are referring issues that are very relevant to the problem of knowing and its relation to information. In this case information processing by machines.
(ii) Under abstract you place a rather introductory statement. Check what I said to your AI entry. The same applies here.
(iii) You refer the Lucas-Penrose constraint in several places, but this should be explained. I understand that In the article of Oppy and Dowe it is explained, but a reader can fail to understand what you're talking about if doesn't know about it. Actually since it is connected to the Gödel's incompleteness theorem you can refer to the corresponding article of the glossariumBITri, incompleteness, and more indirectly to Turing's halting theorem.
(iv) Sometimes I feel bellow your English a German structure that English cannot support. You need bearing in mind that English structure is much more simple than German one, and requires shorter sentences to make the points clear] 


Alan Turing wrote his paper involving the question of whether machines can think, at the Manchester University Computing Laboratory. To him, the question was rather ambiguous as the terms “machine“ and “think“ were very much defined by the common semantic use. So Turing sought to "replace the question by another" (Turing, 1950, §1). He proposed the "The Imitation Game", which later came to be dubbed the "Turing Test".

1. The Machine in use

In his paper, Turing (1950, §3) defines what is being referred to with “machine“. [If the following is a kind of definition of a machine, please review the expression] He states that it is wishful to allow a machine of any manner of operation and constructed with any engineering methods. Adding to that it must not be "[man] born in the usual manner" (Turing, 1950) [I don't understand, sorry]. Thus Turing (1950) goes on to determine that only digital computers shall partake in the game, admitting that the “identification of machines with digital computers,[…], will only be unsatisfactory“(Turing, 1950), if the computer fails to act appropriately, therefore failing at the Imitation Game. Furthermore, he contradicts the possible opinion that the Imitation Game should be applied to all at the time existing digital computers at the moment [I wasn't wrong but so it's easier to read], by arguing that it is not the Imitation Game's purpose to determine whether all computers are capable of thought. Instead, the question to be answered is whether a possible computer could succeed.

Turing(1950, §1) defines the machine to consist of these three parts: (i) Store, (ii) Executive unit, (iii) Control. By his definition, the (i) possesses all the instruction sets needed for the respective tasks at hand and send data packets out to (ii) and (iii). These data packets can carry information and instructions, which can further refer to other packets and their contents, allowing a long chain of instructions, conditional operations and even loops. Unit (ii) receives these data packets and executes the instructions, thus processing the information. The result of the Instruction is then either returned to (i) or used in another process. Unit (iii) oversees both (i) and (ii), ensuring the correct order of instructions and processes is followed. This system of three units can solve all the tasks a human-computer - a human following a set of rules or instructions to accomplish something - can.

Beyond the comparison to a human computer, Turing(1950,§4-§5) concludes that as long as the digital computer has a plentiful, finite amount of storage and a finite amount of states it can be in – a state being the information in storage, if seen as a continuous finite sequence (e.g. state1:256304012 and  state2:239030501) – it can replicate the behaviour of any other machine with a finite amount of states, by simply following an appropriate instruction set to replicate the other‘s states and changes induced by input. [You need structuring previous sentence differently to improve readability; composed by more simple sentences] The characteristic of possessing a finite amount of discrete states makes a machine a discrete one. Through this Turing(1950) decided that a digital computer is universally usable, as it's capabilities are only dependent on the correct instruction set being deployed, not in the way it operates, since any discrete state of a discrete machine can be mimicked. Through this Turing established that any digital computer with an appropriate program may be used for the Imitation Game, no matter its internal mechanics, thereby absolving the outcome of the Game from any dependency on mechanical, electrical, in summary, anyor any other physical properties. The focus now solely lies on the occurring interactions.

2. The Imitation Game

The Setup starts simple. A man, a woman, and another interrogator, whose gender is irrelevant to the experiment, are deployed. Each of the subjects partaking is put in separate secluded rooms. Under no circumstance will the interrogator have audio-visual contact with either of the subjects. He only knows that there are a Man and a Woman to interrogate, each of which receives a gender-neutral identifier. Turing used the Letters X and Y. Furthermore, he used A and B as identifiers for who is Man and Woman respectively. In that Manner the Interrogator’s Conclusions were to be either “X is A and Y is B“ or “X is B and Y is A“.

The only form of interaction between the interrogator and Subjects is to happen via typewriters and a telecommunication line with teleprinters at each end. To adapt this experiment to modern methodologies, we shall use computers connected via an intranet. It's the interrogator's task to figure out who of the subjects is the man and who is the woman. This must be done only by asking each numerous questions. It is A‘s task to convince the Interrogator that he is B, and it is B’s task to help the interrogator figure out that it is in reality B. Both subjects are allowed to lie, which leaves the interrogator to judge by their respective answers.

With the basic setup and tasks complete, Turing suggests to replace the man with a machine following the earlier defined guidelines, therefore being a digital computer and thus replaces the question whether machines can think with the questions of what will happen if the machine is deployed and whether the interrogator will decide falsely less or more times than when the Man was present. Due to the non-physical interaction between interrogator and subjects, the machine’s physical manifestation carries no consequences to the game’s integrity. The machine merely has to be able to communicate with the interrogator.

3. Turing‘s Objections

Turing, however, does not immediately answer the question of what will happen when a computer is introduced, instead contradicting arguments that would instantly falsify the game’s results, if the computer were to actually succeed. Through this the assumed gaping difference between human and machine is bridged.

(1) He firstly objects to the theological Objection [I would say here "argument". What do you think?] that there is a metaphysical part to thinking, as it is the product of some sort of soul in connection with the body, by stating that there are, firstly many sincere objections to substance dualism and theism, secondly very little scientific observations that prove that machines are excluded from receiving a soul.

(2) Moreover, he contradicts the mathematical objection that following Gödels Theorem and the Lucas-Penrose constraint [Provide here either a short clarification or a reference, or even better both], there will be questions the machine will either answer wrong or not at all. He shortly states that this does not automatically rule the machine to be inferior, as it is only an unproven statement that the human mind is not subject to the Lucas-Penrose constraint. And even if humans are free from the Lucas-Penrose constraint, seemingly allowing the assumption that computers are distinguishable by them being subject to it, it begs the question whether there is an entity imaginable, capable of thought yet still being subject to the Lucas-Penrose constraint. If that is the case, consequently such an entity would fail the Imitation Game, therefore be falsely determined incapable of thought. Thus the objection purely through mathematics cannot be valid. [Provide here the reference where this is further elaborated. I suppose it is either Oppy & Dowe or Turing]

(3) Further Turing(1950, §6 (4)) answers to Prof. Jefferson’s statement in his Lister Oration for 1949, quote:

“Not until a machine can write a sonnet or compose a concerto because of thoughts and emotions felt, and not by the chance fall of symbols, could we agree that machine equals brain – that is, not only write it but know that it had written it. No mechanism could feel (and not merely artificially signal, an easy contrivance) pleasure at its successes, grief when its valves fuse, be warmed by flattery, be made miserable by its mistakes, be charmed by sex, be angry or depressed when it cannot get what it wants."(Originally Jefferson G., 1949, quoted from Turing, 1950, §6 (4))

by saying that

"According to the most extreme form of this view, the only way by which one could be sure that a machine thinks is to be the machine and feel oneself thinking."(Turing, 1950, §6 (4)).

This consequently allows the assumption that the same goes for man, meaning any man’s, who you are not,  [Is this phrase needed?, clearly not in that place, i.e. in between the Saxon genitive structure] ability to think and feel can be questioned. As this stance is absurd, thus the generally accepted assumption that all men can think and feel might as well be widened to include computers. Furthermore, if one were to create a computer which would if interrogated about e.g. a sonnet it created, give answers satisfactory to allow it the ability to think and feel, it remains questionable whether it is merely artificially signalling these answers, as Jefferson (1949) would say.  [I understand the sentence, but I dare say an English speaker would have a hard time understanding it. Please, review it]

(4) In a similar manner, Turing(1950, §6 (5)) respond to the claims that a computer is unable to do XX being numerous things of which he gives examples which I will not feature for the sake of compactness. He classifies these statements as merely based on the people's experience with computers, therefore being satisfiable by simply creating a computer that can do X.

(5) Another objection is Lady Lovelace’s statement that Computers cannot be the origin of anything new, for they only do what we order them to. Turing counter-argues by questioning whether there is anything "new under the sun"(1950, §6 (6)), meaning that it is uncertain whether any original work is not merely the result of outer influences or the following of rules. In addition, he contradicts the variant that a computer cannot take one by surprise, by stating that he is in fact often taken by surprise by computers, simply because he does not conduct sufficient and immaculate calculations. This might as well be interpreted in the sense [what do you think?] that anyone's behaviour can be predicted if enough research and calculations are conducted, meaning that even humans can not surprise.

(6) Furthermore, Turing once again turns his attention to the discreteness of machines and argues that, however substantially different a human brain's way of operation is from a digital computer's [I suggest: "..., however substantial difference between the operation mode of human brains and digital computers"], the latter could be able to simulate the brain's processes within a certain margin of error, which would go unnoticed by the interrogator in the game. Since he neither notices the errors nor knows of the operational ways of the subjects he is interrogating, to him there is no difference to him in between the discrete machine and the continuous brain, therefore the difference in construction is to be considered irrelevant to the result.

(7) With regard to determinism, Turing proves that if determinism applies, then both humans and machines follow rules of what they will do, thus contradicting the statement that only machines follow certain rules in what they will do, whereas humans do not. If however, determinism does not apply, meaning humans do not follow rules in what they will do, then computers are as well not subjected to determinism, meaning that a computer made to behave non deterministically can be created.

(8) Lastly, Turing turns his attention to the argument of Extra-Sensory Perception. Although stating that there is very little scientific base for telepathy, clairvoyance, etc. he accepts to include these as variables influencing the interactions, therefore proposing to conduct the game in ESP proof rooms. Furthermore, he states that there is also no basis on which may exclude machines from benefiting from possible ESP-phenomena as well.

4. Conclusion

Alan Turing was able to create a test which puts a computer up against a human in a purely psychological game. The Imitation Game, now the Turing Test, however, does not allow exact conclusions, instead, it has to be interpreted. On the one hand, a machine that passes the Turing Test may only be a perfectly programmed machine, that merely executes commands and gives the right output, without ever truly thinking (see Chinese Room, Artificial Intelligence). On the other hand, a computer that is so extensively and thoroughly programmed as to have developed a mind of its own would pass as well, meaning that a passing result does not allow a definite conclusion. Instead, a passing result could certainly be considered an assumption of intelligence being present. The mere assumption, however, does not have to be bound to the actual possession of it.

The Imitation Game, for all it may not be, still proves itself a good basis on further testing of entities which are suspected to inherit [I think "posses" is better, we're not talking about the inheritance of thinking, right?] intelligence. It should still be noted that problems with the Turing Test do indeed exist. Firstly a passing result might still be an error, as the Interrogator only judges which subject behaves more intelligent, meaning that any conclusion is still dependent on the probability of correctness of the result. Secondly, it is not quite determinable whether intelligent beings suffer from the Lucas-Penrose constraint, meaning that if e.g. humans were to be interrogated by a being of higher intellect which suffers less from the Lucas-Penrose constraint were to fail the Turing Test, and be falsely classified not intelligent. [I don't know whether talking about degrees of suffering Lucas-Penrose constraint is correct. I think it is a rather dichotomic question] Thus it is to be questioned whether the Turing test is not in fact merely a measure for possibly present intelligence, as the Interrogator makes the final judgement.


With respect to the interpretation, it still remains unanswered what else is required to be asked in order to determine an entity’s level of intellect with absolute certainty. This is in close relation to the question of what is needed to form intelligence. As the Turing test does not give any absolute conditions for the presence of intelligence, further more precise tests will depend on our very understanding of intelligence and how it is formed. Turing dedicated the last ten pages of his paper ‘Computing Machinery and Intelligence‘ to the so-called ‘Learning Machines‘, a concept which proves interesting for further research on Artificial Intelligence, results of which might very well apply to Intelligence in general. [You may know there's a lot of development in learning algorithms, deed learning and the like. All this field of knowledge and development can be considered inheriting Turing's proposal] But credit is due where it is deserved, since the Turing Test gave rise to the research of A.I., enabling other experiments such as The Chinese Room and The Chinese Gym. Beyond Intelligence, the Imitation Game might very well be applied to research on the notions of mind and programming. Any program able to pass numerous Turing Tests in succession clearly is able to adapt its answers to the circumstances, as several interrogators may ask the same question in different contexts each, consequently meaning that the program can connect the previously said and perceived information to form a seemingly semantic reason, a feature of an intelligent mind. Of course one has to note that such programming might just be smart syntactic logic manifesting as an apparently semantic connection. [A programmer can identify contextual differences and apply context-dependent algorithms. This is indeed constantly done in internet search engines which adapt answers to individual assumed interest (or buying potential likelyhood)]


Oppy, G. (Author), Dowe, D. (Author) & Zalta, E.N. (Editor) (2018). The Turing Test. The Stanford Encyclopedia of Philosophy. Spring 2018.

Hodges, A. (Author) (n.D.). Alan Turing internet scrapbook. [2018, Nov. 22]

Turing A. (Author), King’s College, Cambridge (Editor) & Southhampton University (Editor) (1950). Computing Machinery and Intelligence. MIND: a Quarterly Review of Psychology and Philosophy. King’s College, Cambridge(Publisher and Owner of Turing Digital Archive). [2018, Nov. 22]

Wikipedia authors (2018, Nov. 19). Turing test. Wikipedia. [2018, Nov. 22]

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