Suppose we have already made a robot which behaves exactly like a human being. When you talk to him, you do not even realize that you are talking to a robot. The kind of face expressions he makes, the way he talks, the way he behaves makes you feel that he is in reality a real human being!
When you pinch on his hand, he tries to save himself by taking his hand away, with wrinkles on his face, exactly like a human being. This makes you feel that robot is actually feeling the pain. Lets further try to dig into it and find out what is happening inside it. Lets try to see what must/can be happening inside such a robot.
Lets take the case of his behavior when he is pinched on his hand. Since this is a robot which can behave exactly like a human being, so there must be touch sensors spread all over his body. When his hand is pinched, some touch sensors recognize the pressure and send a signal to the operating system installed somewhere in the robot. This signal comes to operating system in the form of an interrupt. There must be an interrupt vector in the operating system which maps this interrupt to a subroutine which is supposed to execute. As soon as operating system receives the interrupt it triggers the corresponding subroutine. In the subroutine it is calculated how much pressure on what location is applied and correspondingly what action need to be taken. This action is also predefined or learned on the basis of past training. In this particular case it happens that robot takes his hand back and makes a wrinkly face. This is all what could be happening inside the robot, an interrupt giving rise to the execution of a program, giving rise to the movements of some limbs. One might say that this is very naive explanation of activities going on inside the robot. I am ready to take any kind of complex processing/model you can bring. You can bring as advanced data mining algorithms as you can, you can bring as complex artificial neural networks as you can, you can bring any kind of “computational” model as you can and make a robot which behaves the way I described and give an explanation of what is going on inside the robot. I am ready to take your version of robot.
The question which comes here is when this robot is pinched on his hand, did it actually feel any kind of “pain”?
I say a strict No. If you say Yes, then you must explain how and where? I could not see any place in robot either hardware or software which may be responsible for the “feeling of pain”. What we have done in above example is, we have made a robot which is “behaviorally” same as a human being, but can a robot be “intentionally” same as a human being? We can simulate the “expression” of pain but can we simulate the “feeling of pain” itself?
There may be a lot of processing happening inside the robot, it may be as complex as you can imagine, but processing doesn’t imply there is some feeling inside it. If there is feeling then our computers, tube lights, fans, geysers any kind of complex devices will start “feeling” different kind of things, but we do not see any kind of manifestation of this.
Here it is implied that any kind of “computational” model is not sufficient for realizing “feelings”. One can simulate the behavior/expression part of it but realizing feelings is entirely a different case than simulating it.
This thought experiment also negates the possibility of Strong AI. Strong AI presumes that a machine can realize all the human phenomenon. In above thought experiment we see that it is not possible. It shows that Strong AI is wrong. A robot is nothing but a feelingless mechanical device. It is not that in a machine feelings are partial or to some percentage, they are absolutely zero. It is also not that with the advancement of science and technology, in future we will be able to develop a robot which will be able to realize all the human phenomenon. A robot can “never” feel pain or anything, independent of how advanced science and technology become. It is “in principle” not possible for a robot to feel pain.
I know it will create a lot of questions and arguments in readers minds for which I request them to comment on this blog. I would like to suggest readers to limit themselves to the machine and then discuss the issue rather than coming to a human being. Believe me discussing a machine is easier than a human being.
Please read following article I wrote later to understand the concept much deeper: