Roger Penrose would insist that computers can never do all that hu- man minds can, nor even simulate those activities. John Searle also believes that it takes more than mechanical computation to constitute thinking. He calls the belief that computation is the same as thinking “Strong AI,” and rejects this in favor of “Weak AI”—while computers can simulate human thought, the simulation of thinking is not neces- sarily thinking.
In 1980, Searle gave what is probably still the best-known rebuttal to Strong AI, the “Chinese Room” scenario, which emulates how a computer works. Imagine that you are asked to answer questions pre- sented to you in Chinese, although you speak only English.You se- quester yourself in a room containing many tiles marked with Chinese symbols (the database) and a book of rules written in English (the program).Questions,written in Chinese,are presented through a small slot (input).You (the CPU, central processing unit) match the incom- ing Chinese characters to entries in the book and then manipulate the Chinese character tiles as the book directs. That leads to new Chinese characters, the correct answers to the questions, which you present to the world through another slot (output).
The heart of Searle’s contention is that although this process en- ables you to obtain correct answers, in no way do you understand Chinese as you obtain those answers.The distinction is between what a computer does, which is to manipulate formal symbols like Chinese characters, and what our minds do, which is to add meaning to the symbols.Hence, concludes Searle, although his hypothetical computer passes the classic Turing test administered in Chinese, “programs are not minds,” and a computer or robot can never be conscious.
Many serious objections have been raised to the Chinese Room. One counterargument holds that, whether the person in the room understands Chinese or not, the system as a whole—database, CPU, and so on—does. Other reactions pit the scientific stance against the philosophical one, a common theme in consciousness studies (in my opinion, the answers will come from science, but the philosophical questions are invaluable in pinpointing the issues). Dennett, for in- stance, warns that the Chinese Room acts to dissuade people from