Mortimer Adler lectures; Man and machine, part 2

If this can be done it would show. According to Dr Lily the Dolphins had the power of conceptual thought and I would agree with them that they had it if this can be done. The assumption here to be tested is either that the Dolphins already have a language of their own which men can learn and use to converse with them or the Dolphins have large enough brains to be taught human language and either Sumption the test calls for two way conversation between man or man and dolphins and conversation that exhibits conceptual thought as much as a conversation between men or at least between an adult man and a small shock. Dr. Lee recognizes all the difficulties to be overcome in making a test of this sought. But he is hopeful that it can be done and will turn out to be successful. Let us ask therefore what we would learn from the results of the test the test that he envisages first. If it fails and second it succeeds those are the two possibilities that will be. He'll try again and again I will try it will fail or they'll

try it and it will succeed. What will we learn if it fails or if it succeeds. If the test fails the negative result can be interpreted merely as a failure to overcome the difficulties already seem to be inherent in the effort of men to engage in conversation with a non-human species. Failure would not decisively show that the Dolphins lacked enough brain power to engage in propositional speech. If the test 16s the positive result would be open to two interpretations. Though the positive result might help us to ascertain more precisely the critical threshold in the continuum of brain magnitude above which propositional speech can occur. You would not by itself be decisive as to whether a certain magnitude of brain is the sufficient the sufficient or only a necessary condition of propositional speech and conceptual thought. The point I'm now making is exactly

the same point that I made earlier with regard to the car relation between stages in human brain growth and the first appearance and subsequent development of propositional speech in the human child. Hence if the Dolphins can converse with us in a manner of exhibits their power of conceptual thought we are left with these two possible interpretations of the fact. Either by a certain magnitude of brain is the sufficient condition of conceptual thought in which case there is no need for an immaterial fact in order to explain it all even all our a certain brain magnitude is a necessary but not sufficient condition of conceptual thought. And so in the dolphin as well as in man and immaterial fact it must be operative. Let me add one for the common. If experiments with the bottlenose dolphin cannot decisively resolve the issue then are 40 already. No

others are logical evidence can decide the question first because among the higher mammals only the dolphin has a brain relative brain weight that approximates the relative brain weight of man. And second because similar efforts with other animals even if successful would be open to the same two interpretations that apply to successful outcome of efforts with the dolphin. That being solved only one sauce of decision is left to us. That which may be provided by the technologists in their effort to produce machines that simulate human intelligence including man's power of conceptual thought. As that is manifested in propositional speech this brings us to the third and last problem of the Cartesian challenge. The challenge to the technologists thaw for preliminary clarifications are necessary if you understand this crucial this crucial point in the first place. It is necessary to distinguish between computers computers

that are programmed to perform in certain ways. And what I'm going to call robots are machines built for the purpose of simulating human intelligence in its higher reaches of learning problem solving and discovering deciding in sulfa we can eliminate from further consideration. All computers that are completely programmed the program computer. Not does only what it is programmed to do. The program that is put into it by man determines its performance. A certain output on the basis of a certain input you can be programmed moreover only for performances that are logical. Its chief superiority that man lies in its speed and its relative freedom from ARA is chief utility isn't serving man by extending his pala just as a telescope or a microscope does. Robots in principle are different from program computers instead of operating on the basis of pre-determined pathways laid down by programming. They operate

through flexible and random connections. They may have what the great English mathematician in this field. And Turing calls infant infant programming. Some few facts connections that are like those built into the human infant at birth. But for the purpose of simulating human intelligence in its higher reaches the robot must be able to learn from its own experience and must be teachable as the human being is like human beings and unlike computers robots must be capable of making errors making errors that are not wholly explicable by mechanical defects as are the programs and as are the errors of program computers. In the second place we must distinguish between the simulation of human behavior and processes and what is called a replication of them. The attempt to construct mechanical models that operate in the same way that the brain operates. Our efforts at replication most of the

efforts up to the present have not gone beyond the stage of mathematical theory and the drafting board. A few actual models such as the McCulloch pits nerve net have been constructed these attempts to replicate the action of the central nervous system have been criticized by leading the religious on two grounds. First on the ground that we do not yet know enough about the action of the central nervous system to attempt its mechanical replication. And second on the ground that all such efforts are severely limited by the crucial difference between the electro chemical action electro chemical action of the central nervous system and the purely electrical action of the mechanical models. In contrast to replication the simulation of human behavior by machines consists in achieving the same end result in the way of performance but not achieving it in the same way. That's for example airplanes to simulate the flight of birds but the mechanics of flight the

mechanics of flight and not the same in both cases though both bird an airplane of a the same laws of aerodynamics. Machines have been built to simulate trial and error learning pattern Wreck-It pattern recognition chess and checkers playing. Working with hypotheses carrying out a systematic search for solutions to a problem. But in all these cases the machine whether a program computer or something more like a robot achieves the result well without the working of his machinery replicating the neurophysiological processes of the human being who accomplishes the same result. We can ignore replication and concern ourselves only with a simulation for the Cartesian challenge only calls for machines that can simulate conceptual thought. As that is exhibited in human conversation. In the third place we must distinguish in this field of technology so new so lively so active between actual achievements and theoretical promises for the future. As might be expected the claims that are made both with respect to

mechanical devices now actually in operation and also with respect to the theoretical possibilities that we realized in the future range from the very modest At one extreme to the most extravagant at the other. The explanation of the deficiencies in existing apparatus where they are admitted tends to support the prediction that the machines of the future will come much closer to simulating human intelligence than any now in existence. The magnitude of the human brain in componentry the number of neurons is very very large number ten to the tenth power 10 to 11 power and the magnitude of the circuitry. The number of connections is very much larger than magnitude of the existing machinery is very much smaller both in componentry the number of transistors is about 10 to the three and then circuitry. Until machines are built that more closely more closely approximate the magnitude of the human brain as for example the magnitude of the Dolphin's brain more closely approximates the magnitude of the

human brain. Until that happens it is unreasonable to expect an un programmed robot to simulate the most characteristic of human performances such as learning a language like English and using it conversationally. The ONLY FOR point that for the point to be made here is that there is no reason in principle to the nigh the possibility of building a robot that will have a component and a circuitry equal in magnitude to or even greater then the magnitude of the membrane. No one not even the most extravagant among the technologists claims that a robot now exists. The robot now exists that can meet the Cartesian challenge though as we shall see presently. There are many theoreticians in this field who do not hesitate to predict that one will be produced in the future in the fourth place and final. This is basic. We must carefully now at the challenge to future technologies is very precise. It does not call for the production of

a robot whose performance will provide us with an answer to the loose and unclear question. Can machines think. The literature concerned with computers and robots quite properly disputes dismisses that question as so loose and some ambiguous that there is no way of deciding what the correct answer is. It is used by psychologists neurologists computer technologists and philosophers. The word think has so many meanings in its application to animals men and machines that have one as can animals think or can machines think. The answer must be yes in some senses of the word and know in other senses of the word. No one has yet produced an acceptable definition of human thinking in all its variety that will serve as a standard for measuring the success of efforts to produce a robot that will simulate the whole range of human thinking. Fortunately in order to make a critical test of artificial a machine intelligence it is

not necessary to do so. To do what might always be impossible namely gain general acceptance for a definite definition. A definition of human thinking in all its variety. The Cartesian challenge to the technology is calls for a very specific performance by some future robot. A performance that would sufficiently indicate that the robot had the power of conceptual thought by virtue of the fact that the robot could use propositional language conversation conversationally what justifies our inference that men have the power of conceptual thought that other animals lack this power. It is the fact that men have and other animals lack propositional speech. This being so we would be we would be equally justified in attributing the power of conceptual thought to an unproved Graham robot. And I was able to engage in conversation in English and by the same token we would be justified denying that robot that not a robot failing this test had the power of conceptual thought. No matter what other intelligent

or apparently thinking behavior the robot manifested. In the light of the foregoing clarifications and with this problem of the Cartesian challenge now made clear as sharp as possible. We are now in a position to appreciate the remarkable fact when an English mathematician just recently dead one thousand fifty four A.M. Turing has picked up a gauntlet thrown over 300 300 years ago by Descartes Turing's widespread fame in the world of computers and robots and the currency of such phrases as Turing's game and Turing Machine centers on his claim that it is mathematically possible to conceive a robot that will successfully need Descartes challenge Turing machine is a mathematically conceivable robot of the future who will be able to play Turing's game as well or almost as well as men can play. Turing's game is a conversational fair and

conversational affair using an ordinary language such as English. It is derived from a game in which all the players are human beings. Two of the players are behind a screen and one of them is male the other female. The third player is the interrogator who asks the hidden participants questions in an effort to determine which one is male and which female. The questions unlimited as to content of a riot are submitted in typewritten phone and the answers are returned in typewritten form so the tone of voice is eliminated as a clip. The hidden play is not required to tell the truth in answering. They can say anything they think they can say anything that they can think. If they think will serve to prevent this meddling Dick being detected. Now the tour of this at the Old own game now the touring version of this game simply substitutes a robot for one of the two human beings instead of a male and female you have a human being and a robot. All the rules

of the game remain the same but the problem becomes one of determining which hidden participant is a human being and which is a robot is the game play. Now if he were confronted with if he were confronted with Turing's gang I am absolutely sure of the De Kock would say that they caught would say that no machine could enter the bill they would be able to participate in it at all much less be able to play it as effectively as human being. Turing's claim on the contrary is that a robot participant in his game is now theoretically conceivable and that with the development of technology his theoretical model can someday be actually produced in the form of machine that will use an ordinary language as English with the conversational flexibility and resourcefulness required to play the game effectively. Is Turing's answer that they cock challenge clear. Now among competent scientists and technologists there are many differences of opinion about

Turing's claims ranging from dismissal dismissal of it as unfounded to endorsement of it is sound. For reasons already given we can ignore the types of criticism which says that human thinking involves much more than the ability to play Turing's game effectively. It may indeed but playing Turing's game would satisfy our criteria for attributing to the robot that played it the power of conceptual thought. We can also ignore those who point out the numerous difficulties that have so far been counted in programming computers to use an ordinary language such as English. All those who go further and maintain the touch programming is inherently impossible. That too may be the case but Turing machine will not be a programmed computer. It will be a robot with no more than infant programming. A robot able to learn English and learn how to use it conversationally. One further comment. The question is not whether Turing's mathematical theorizing is sound. It is rather whether the robot he

envisages will ever come into existence and operate as intended only if and when it does. Well the third prong of the cod tease and challenge be successfully met. Now let us for the moment suppose the Turing's claim is validated at some future day. It's certainly possible with the significance of this fact the entirely clear I will point out that the experiment with dolphins neurological research is not entirely clear if it's indecisive would this be decisive. Or with there still be some ambivalence about it. In the case of the Dolphins remember we observe that success in engaging with them in conversation could be interpreted in two ways. We would have to admit that they had the power of conceptual thought for the same reason that we attribute it to men. But as we saw experimental success with the Dolphins would not be decisive with regard to the question of the brain or a certain magnitude of brain was sufficient. Was this

sufficient or only a necessary condition of conceptual thought. Now can there be more than one interpretation. Can there be more than one interpretation of success in producing the Turing machine. Theoretically theoretically the answer is affirmative yes that Candy there are to that Candy. Theoretically two possible interpretations on the one hand we could say that an immaterial fact is present in the machine as well as in man in view of the fact that both have the power of conceptual thought. And if you have a theory that conceptual thought involves an immaterial fact it at least according to the direct argument given earlier in this lecture. On the other hand we could say that since the machine is entirely material in the Constitution and since the machine exhibits the power of conceptual thought no immaterial fact is required either for the robust performance of a man's. But while both answers are logically possible the first the first of those two answers can be dismissed as fanciful rather than

serious. For it involves an invocation of ghosts or pixies. After all we built the machine step by step and every component added into its construction was a material component. To claim the first answer seriously would have to claim not seriously I hope that while you weren't looking and immaterial fact it crept in. And. In the works. We have thus left we are best left with only the second interpretation of success in the production of Turing's machine. And according to that interpretation no immaterial factor is needed to explain the possession is if we have it. A Turing machine that succeeds in playing the game. We are led to the conclusion that no immaterial fact is needed to explain the possession by a machine or by man of the power of conceptual thought as exhibited in propositional speech. The Cartesian challenge would be satisfactorily met. More than that the conclusion of the direct argument for the immaterial of conceptual thought would be falsified by observable

facts and be obligated to re-examine the private premises and the reasoning to discover the source of the era. An ancient philosophical issue would have been resolved now not a few moments more. To sum up so that I put all this together in view of everything said What is the future of the next question about the difference of man. At the present time the state of the next question but it can be described as follows. For it to make up its philosophical aspect then a valid scientific aspect in its philosophical aspect at the present. John we have an opposition between two well developed and reasoned view. On the one hand we have the position of those who think that sound philosophical reasons support the conclusion that an immaterial factor is required to explain conceptual thought. Let us call this the immaterial his position on the other hand we have the position of those who think that sound philosophical reason supports the conclusion that conceptual thought

can be identified with neuro physiological processes. Let us call this the materialist position. Now contemporary exponents of the materialist position include philosophers many of them who are conversant with computer technology and the theory of robot such philosophers as Michael Scriven Jaycee's smart Donald Mackay Wilford sellers Steven Toolman all of whom see no obstacle in principle to the production of a robot that conforms to Turing specifications. One who can participate successfully in the game. There are a few however of any contemporary exponents of the immaterial his position. Who appear to be conversant with computer technology and the theory of robots. But in principle philosophers who hold this position should bet heavily against the likelihood of success in the effort to produce a Turing machine effectively able to play the game. So that's the that's the philosophical position of its scientific aspects. We have a great deal of relevant evidence

and the promise of much more to come. But none of it none of the evidence we have is at present decisive with respect to the philosophical issue that I just stated that lies at the heart of this mix question. If we look to the future for decisive evidence we must for reasons already given in this lecture concentrate on the third prong of the Cartesian challenge and consider the logical effect on the philosophical issue of success or failure in the effort to produce a Turing machine able to play the game effectively. The positions that constitute the philosophical issue at the heart of the mix question the materialist and the immaterial is position can be regarded as hypotheses each with a different prediction about the future outcome of efforts to produce a Turing machine. The immaterial as provision predicts failure in this venture and its exponents are reasonable rather than dogmatic in their espousal about hypothesis. They should be open to the falsification of their

hypothesis. So far as I can see success in the Turing venture would falsify the immaterial hypothesis. That in turn would have won for the consequence if with the falsification of the immaterial his view the action of the brain is acknowledged to be the sufficient condition of conceptual thought. Then we must conclude that man's difference in time from other animals is only superficial not radical. It is generally agree that man's power of conceptual thought is the root. Of all the observed behavioral differences in common between man and other animals. Not only his sentence making but as to making his history making his law making his institution making him sullen. Hence if his power of conceptual thought does not support the proposition. That man defeated radically in kind from other animals. We must a brain embrace the other alternative namely that he differs in kind only superficially the materialist position on the

other hand predicts success. All the leading materialist philosophers that I've read recently predicts success in the terror in the Turing venture and you would certainly the materialist position would be strongly confirmed by the eventuality of such success. But unlike the image tearaways the in materialist position the materialist position cannot be falsified by failure in the Turing venture. As we saw in the case of the projected experiment with the dolphins repeated failures while discouraging can always be attributed to experimental deficiencies are obstacles and so they need not be interpreted as definitely showing that the Dolphins lack the capacity for propositional speech. So here likewise failure in the Turing venture can always be attributed to technological inadequacies or to obstacles that have not yet been overcome in practice even though in principle they are not insuperable.

Nevertheless if the trial is may be edited. If it is made again and again to produce a Turing machine they will play the game. And success is not a chain. Time after time after time such repeated failure is to have some logical effect. This is of the utmost importance to understand that as the long future lies ahead of us when we want to this is going to happen if we succeed we fail. If we try and try and try again and succeed or we try and try and try again and fail. The logical principle that becomes operative he is papa's principle that a theory or hypothesis which is repeatedly put to the test and is not falsified gains credibility. It requires an increasing degree of relative truth. It tends more and more to be confirmed in this truth even though it can never be completely confirmed with finality as having incorrigible or and debatable truth in the light of this principle. We are justified in saying that

the materialist hypothesis having submitted itself to a decisive test in terms of the third prong of the Cartesian challenge would gain some measure of relative truth by the failure of each serious attempt to produce a Turing machine. However the number of attempts that can be made is as indefinitely large as the amount of time in which men can make the effort. Hence there is no point at which you can be said that the technologists have definitely failed to meet the Cartesian challenge. On the other hand if the exponents of the materialist position are as reasonable as underdog Matty as we expect the immaterial is to be then repeated trials and failures in the touring venture should have the effect on them of diminishing the credibility the relative truth of their view in

proportion as it tends to confirm the materialist hypothesis and to increase its relative truth. The future of the next question about the difference of man involves two major alternatives. Either we will have either eventual success or eventual success in the touring venture that will decisively settle the question. All will come as close to doing that as can be expected in matters of this kind and we will know so far as we can do anything by scientific evidence that man differs only superficially in time. All either all with attempt after attempt being made repeated failure in the Turing venture will progressively confirm the truth of the immaterial his position and whether the truth of the proposition that man differs radically in kind from other intelligent animals and from apparently intelligent machines. These being the alternatives for the future how long the future I do not know.

These being the alternatives for the future I will try in the next in the last lecture of this series to assess in advance the consequences that follow from the future realisation of one or the other of these alternatives. What difference does it make to us if man differs only superficially in kind from other animals of the it that you come out to be true. What difference does it make to us if man differs radically in kind from other animals and from machines. These are the questions I will attempt to answer next time. You have been listening to man and machine. The fourth of five lectures about the difference of man and the difference it makes. Our guest speaker for the 1966 Britannica lecture series given at the University of Chicago is Mortimer J Adler director of the Institute for philosophical research. Next week Mr Adler will give the concluding lecture. The difference it makes the difference of man and the difference it makes is produced for national educational radio by the University of Chicago.

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