June 5, 2019
In 1950, Alan Turing had proposed a question which led to many criticisms in the world of computer science. What made the question so special was the fact that it was a time when the term “artificial intelligence” was not even born. Since then, there had been many opponents and supporters of the question that he proposed. The question was: “Can machines think?”
As also agreed by Turing, the definitions of the terms “machine” and “thinking” are very ambiguous. [1] Therefore, he replaces the original question with his famous Imitation Game also known as the Turing Test which is a test of whether a machine can demonstrate intelligent behavior that is indistinguishable from that of a human. The test is a game of two rooms where in one of the rooms a human and a computer resides, and in another, an interrogator is present whose task is to determine which one of the two is the human and which one is the machine. Through the scope of this game, Turing states that there is little point in a “thinking machine” looking, sounding or feeling like a human for testing its intelligence. Due to this reason, he suggests the use of the term “digital computer” instead of the term “machine” to overcome the ambiguity that occurs based upon the first question. But what about the term “thinking”? Could a computer be made thinking?
Thinking is associated with cognition. From many cognitive scientists’ view, cognition is computation. Dietrich defines this view as computationalism, and suggests that it has two corollaries. One of them is that computers can think, and the other is the fact that the human mind, itself, is a computer which is also known as the computational theory of mind (CTM). [2] As stated by Dietrich [3], artificial intelligence is considered as a representation of all attempts to build a thinking computer. Therefore, we can safely say that the opinions of Turing led to the beginning of an era through which people had the motivation to build thinking computers. Although a lot of people believe in the view of computationalism, there are others who are the opponents of this theory. Therefore, the most important three contrary views should be first explained before giving an opinion on whether a computer can think.
First of all, there is the objection related to consciousness. A quote by Professor Jefferson [4] tells the following: “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.” Yet, this argument cannot be fully accepted, since a man cannot know how another man thinks unless he is that particular man. This is also why the cognitive scientists do not try to explain consciousness. They only try to explain cognition. Consciousness is about how we all perceive the world.
Secondly, there is the argument that is coming from the fact that the nervous system is definitely not a discrete- state machine which also mentions that a small error in the information may cause a large difference on the outgoing impulse. Turing [1] agrees that a discrete-state machine must be different from a continuous machine. Yet, he states that through the scope of the “Imitiation Game”, the interrogator will not be advantageous regarding to this difference, and says that it would be possible to mimic continuous outputs whenever it is required.
Finally, there is the Chinese Room argument by John Searle [5] which is proposed in his article Minds, Brains and Programs, and also is one of the most famous philosophical arguments. The argument states the following: Imagine yourself locked in a room where papers with Chinese texts written on them are slipped through a slot under the door. You are tasked with taking these sheets, write responses to them in Chinese, and then slip them back from the slot that resides under the door. Yet, the problem is that you do not know Chinese. However, you have a book that accompanies you which is written in English (or another language that you do know). This book consists of a set of rules which tells you what to write in response to a certain Chinese character sequence. You follow these rules, but you do not have any idea regarding to what you wrote, because you do not know the meaning of the responses that you had written. In this argument, the person in the room is analogous to a computer. Given a set of rules, it follows them and tries to accomplish a given task. Dietrich attacks this argument by stating that the person in the room is computing, and there exists some states which only have different contents compared to the content of the on-going conversation. When we take a look from the outside of this room, the Chinese speakers are engaged in a conversation with the person in the room. When we consider the inside of the room, the person does have mental states but these are not related to the conversation, but related to the marks and the rules in the book that has been seen. He also argues that the person in the room and the rule book constructs a virtual machine which is tied to another system that has computational states.
To sum up, there is no proof which shows that the computers cannot think. Based upon the answers given to the arguments that had been presented above, one can see that there is no obstacle on the way to build a thinking computer. On the other hand, there is indeed a huge step that the cognitive scientists should take to accomplish this task. As many cognitive scientists believe, the humans are not special creatures, and the cognition is just a physical process. Thus, as long as this search continues, one may eventually find the right architecture to build a thinking computer.
References
[1] A. M. Turing, “I.Computing Machinery And Intelligence,” Mind, vol. LIX, no. 236, p. 433460, 1950.
[2] M. Rescorla, “The Computational Theory of Mind,” in The Stanford Encyclopedia of Philosophy, spring 2017 ed., E. N. Zalta, Ed. Meta- physics Research Lab, Stanford University, 2017.
[3] E. Dietrich, Thinking Computers and Virtual Persons: Essays on the Intentionality of Machines. Elsevier Science, 2015.
[4] G. Jefferson, “The Mind of Mechanical Man,” Bmj, vol. 1, no. 4616, p. 11051110, 1949.
[5] J. R. Searle, “Minds, Brains, and Programs,” Behavioral and Brain Sciences, vol. 3, no. 03, p. 417, 1980.