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“Any process at all that you can give a formal definition of can be simulated on a digital computer. I can do simulations of rainstorms in London…but nobody supposes a simulation of a rainstorm will leave us all wet. But they think that if we simulate a mind, we have created a mind.”
-Professor John Searle
The American philosopher, John Searle, pointedly challenges the concept that advanced computation can lead to conscious machines that are conscious like people. In the world of artificial intelligence, computer science researchers, engineers and academics distinguish narrow artificial intelligence from general artificial intelligence. Narrow artificial intelligence refers to computer systems that perform specific tasks such as facial recognition or language translation as well as or better than humans. Narrow artificial intelligence drives many applications from self-driving cars to automated fraud detection at credit card companies. On the other hand, artificial general intelligence or AGI refers to machines that would poses or exceed the full range of human intelligence including creativity, self-awareness, awareness of others, cognitive skills, empathy—in other words, full consciousness. However, it is not unanimously decided that AGI is fully capable of having consciousness in the same manner that humans do.
John Searle currently holds the positions of the Willis S. and Marion Slusser Professor Emeritus of the Philosophy of Mind and Language and Professor of the Graduate School at the University of California, Berkeley. He is considered one of the most influential philosophers of our time with contributions to the philosophy of science, language and the mind. In his widely quoted paper from 1980 titled “Mind, Brains, and Programs” published in the journal The Behavioral and Brain Sciences (3, 417-457), Searle outlined his “Chinese Room” thought experiment that argues why machines can never be conscious. In his thought experiment, he describes an English-speaking person sitting in a room who cannot speak Chinese and, for that matter, has no idea of what any Chinese characters or symbols mean. The room is closed to the outside world except for two slots for slips of paper to enter the room and another for paper to leave the room. Inside the room is a desk, some scratch paper, and a detailed set of rules written in English that provide specific instructions on how to deal with Chinese characters. In the experiment, pieces of paper with Chinese characters written on them come through the in-slot. The rules describe precisely what he man must to do with any of the characters coming in and what new characters to write in response (all the while, the man does not understand the actual meaning of the characters he is supposed to write or respond to). The new pages of characters are written and then passed to the outside world through the out-slot. Because the man in the box follows the rules explicitly, a person fluent in Chinese could submit questions in Chinese and receive answers in Chinese that make perfect sense. The impression to the person on the outside would be that the person inside the box perfectly understood Chinese, but the reality is that the person in the box was only following instructions with no understanding of Chinese whatsoever. Searle extends his reasoning to state that computers essentially manipulate symbols just as the man in the box manipulated the Chinese symbols with no real understanding of Chinese whatsoever. In other words, just executing rules does not equal consciousness. Furthermore, Searle implies that our consciousness is produced by our brains. From this point, he concludes that since machines are not biological, no matter how much we simulate the brain in machines it will only be a simulation, not real human consciousness.
In summary, John Searle laid down a philosophical argument using his Chinese Room thought experiment that rejects the possibility of machines becoming conscious. Because computers only manipulate symbols and follow instructions, they cannot exhibit will. They cannot be conscious. He goes further and asserts that our consciousness is the product of our biology and for that reason a non-biological machine can only simulate the human brain never be the human brain. Searle’s Chinese room has prompted many discussions and rebuttals. He may be right that machines may never poses human consciousness, but one may ponder that machines are also made of matter and may obtain a consciousness different from human consciousness but real nevertheless. If you are interested, you can find the PDF of Searle's paper "Mind, Brains, and Programs" here.