Chapter Ten Artificial Intelligence I: Definitional Perspective Historical Perspective Artificial Intelligence (AI) has been a driving force behind our quest to create a machine in our own image. Automata begin to appear for general public consumption during the late 19th century. The advent of electronic computation has led to an information revolution in the 21st century characterized by machines that supply expert advice, control the environment, and emulate human thinking. Philosophical Issues-Man as a Machine Descartes (1596-1650) raises the mind-body question. In particular, “What is the difference between a person and a machine?” “Treatise on Man” includes a comparison between a human being and a hypothetical “statue or machine” that operates like a clock or hydraulic fountain. Descartes proposes that humans possess a “rational soul” whereas animals are not capable of reasoning (“I think, therefore I am.”) Humans have had difficulty accepting two important theories: the earth is not the center of the universe and evolution. Is there a third theory that we need to accept— man is a complex machine? Evaluating Descartes’ Approach Debate over Descartes is religious in nature. The atheist philosophers of the 18th century took issue with the idea that a “soul” separates us from the machine-like model for other animals. • Descartes' ideas came into direct conflict with the teachings of the religious community of his time. • Descartes tries to avoid the conflict; his “machine” is not a man, simply a “statue” that God forms with the explicit intention of making it as much as possible like us. • Mechanical Computation One aspect of an intelligent agent rests on its ability to perform calculations Mechanical calculators represent automata capable of “imitating” human intelligence on a “primitive” level. The abacus is developed in 2600 B.C. In the 19th century, Charles Babbage develops mechanical machines that anticipate the modern electronic digital computer. They are a forerunner of an ultimate “intelligent agent.” Defining AI There may not be a single definition. Alternatives serve to support the authors' special interests. • The cognitive scientific goal of AI is to codify knowledge (and meta-knowledge or “knowledge about knowledge itself”) in order to assemble systems to explain intelligence and consciousness itself. • The engineering goal of AI is to assemble systems using a computer’s inventory of knowledge and facilities in order to solve real-world problems. • Can a Machine Think and Understand? • This question may be pointless. Noam Chomsky suggests it is a question of decision, not fact. We must agree on what defines intelligence, thinking, understanding (and ultimately consciousness). • If a computer passes an “intelligence” test, would we impart intelligence to it? McCarthy and Shannon note that we could “stack the deck”—design a program with preprogrammed responses. • Minsky: “Intelligence” is our name for whichever problem-solving mental processes we do not yet understand. The Turing Test Interrogator Machine intelligence Human intelligence If an interrogator cannot distinguish between machine intelligence and human intelligence then the machine passes the Turing Test (TT) for intelligence. Objections to the TT • • • • • • Theological: Thinking is a function of man’s God-given immortal soul. No animal or machine can think. “Head-in-the-sand” argument: Consequences of thinking machines are too dreadful to contemplate. Mathematical: Some theorems can neither be proved nor disproved. Consciousness: No machine can write a sonnet. Disabilities: Machines can follow instructions but you cannot instruct them to have a sense of humor. Lady Lovelace argument: A machine can never do anything really new.