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artificial intelligence

 
Dictionary: artificial intelligence

n. (Abbr. AI)
  1. The ability of a computer or other machine to perform those activities that are normally thought to require intelligence.
  2. The branch of computer science concerned with the development of machines having this ability.

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Britannica Concise Encyclopedia: artificial intelligence
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Ability of a machine to perform tasks thought to require human intelligence. Typical applications include game playing, language translation, expert systems, and robotics. Although pseudo-intelligent machinery dates back to antiquity, the first glimmerings of true intelligence awaited the development of digital computers in the 1940s. AI, or at least the semblance of intelligence, has developed in parallel with computer processing power, which appears to be the main limiting factor. Early AI projects, such as playing chess and solving mathematical problems, are now seen as trivial compared to visual pattern recognition, complex decision making, and the use of natural language. See also Turing test.

For more information on artificial intelligence, visit Britannica.com.

Sci-Tech Encyclopedia: Artificial intelligence
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The subfield of computer science concerned with understanding the nature of intelligence and constructing computer systems capable of intelligent action. It embodies the dual motives of furthering basic scientific understanding and making computers more sophisticated in the service of humanity.

Many activities involve intelligent action—problem solving, perception, learning, planning and other symbolic reasoning, creativity, language, and so forth—and therein lie an immense diversity of phenomena. Scientific concern for these phenomena is shared by many fields, for example, psychology, linguistics, and philosophy of mind, in addition to artificial intelligence. The starting point for artificial intelligence is the capability of the computer to manipulate symbolic expressions that can represent all manner of things, including knowledge about the structure and function of objects and people in the world, beliefs and purposes, scientific theories, and the programs of action of the computer itself.

Artificial intelligence is primarily concerned with symbolic representations of knowledge and heuristic methods of reasoning, that is, using common assumptions and rules of thumb. Two examples of problems studied in artificial intelligence are planning how a robot, or person, might assemble a complicated device, or move from one place to another; and diagnosing the nature of a person's disease, or of a machine's malfunction, from the observable manifestations of the problem. In both cases, reasoning with symbolic descriptions predominates over calculating.

The approach of artificial intelligence researchers is largely experimental, with small patches of mathematical theory. As in other experimental sciences, investigators build devices (in this case, computer programs) to carry out their experimental investigations. New programs are created to explore ideas about how intelligent action might be attained, and are also developed to test hypotheses about concepts or mechanisms involved in intelligent behavior.

The foundations of artificial intelligence are divided into representation, problem-solving methods, architecture, and knowledge. To work on a task, a computer must have an internal representation in its memory, for example, the symbolic description of a room for a moving robot, or a set of features describing a person with a disease. The representation also includes all the knowledge, including basic programs, for testing and measuring the structure, plus all the programs for transforming the structure into another one in ways appropriate to the task. Changing the representation used for a task can make an immense difference, turning a problem from impossible to trivial.

Given the representation of a task, a method must be adopted that has some chance of accomplishing the task. Artificial intelligence has gradually built up a stock of relevant problem-solving methods (the so-called weak methods) that apply extremely generally.

An important feature of all the weak methods is that they involve search. One of the most important generalizations to arise in artificial intelligence is the ubiquity of search. It appears to underlie all intelligent action. In the worst case, the search is blind. In heuristic search extra information is used to guide the search.

Some of the weak methods are generate-and-test (a sequence of candidates is generated, each being tested for solutionhood); hill climbing (a measure of progress is used to guide each step); means-ends analysis (the difference between the desired situation and the present one is used to select the next step); impasse resolution (the inability to take the desired next step leads to a subgoal of making the step feasible); planning by abstraction (the task is simplified, solved, and the solution used as a guide); and matching (the present situation is represented as a schema to be mapped into the desired situation by putting the two in correspondence).

An intelligent agent—person or program—has multiple means for representing tasks and dealing with them. Also required is an architecture or operating framework within which to select and carry out these activities. Often called the executive or control structure, it is best viewed as a total architecture (as in computer architecture), that is, a machine that provides data structures, operations on those data structures, memory for holding data structures, accessing operations for retrieving data structures from memory, a programming language for expressing integrated patterns of conditional operations, and an interpreter for carrying out programs. Any digital computer provides an architecture, as does any programming language. Architectures are not all equivalent, and one important scientific question is what architecture is appropriate for a general intelligent agent.

In artificial intelligence, the basic paradigm of intelligent action is that of search through a space of partial solutions (called the problem space) for a goal situation. Each step offers several possibilities, leading to a cascading of possibilities that can be represented as a branching tree. The search is thus said to be combinatorial or exponential. For example, if there are 10 possible actions in any situation, and it takes a sequence of 12 steps to find a solution (a goal state), then there are 1012 possible sequences in the exhaustive search tree. What keeps the search under control is knowledge, which suggests how to choose or narrow the options at each step. Thus the fourth fundamental concern is how to represent knowledge in the memory of the system so it can be brought to bear on the search when relevant.

An intelligent agent will have immense amounts of knowledge. This implies another major problem, that of discovering the relevant knowledge as the solution attempt progresses. Although this search does not include the combinatorial explosion characteristic of searching the problem space, it can be time consuming and hard. However, the structure of the database holding the knowledge (called the knowledge base) can be carefully tailored to suit the architecture in order to make the search efficient. This knowledge base, with its accompanying problems of encoding and access, constitutes the final ingredient of an intelligent system.

An example of artificial intelligence is computer perception. Perception is the formation, from a sensory signal, of an internal representation suitable for intelligent processing. Though there are many types of sensory signals, computer perception has focused on vision and speech. Perception might seem to be distinct from intelligence, since it involves incident time-varying continuous energy distributions prior to interpretation in symbolic terms. However, all the same ingredients occur: representation, search, architecture, and knowledge. Speech perception starts with the acoustic wave of a human utterance and proceeds to an internal representation of what the speech is about. A sequence of representations is used: the digitization of the acoustic wave into an array of intensities; the formation of a small set of parametric quantities that vary continuously with time (such as the intensities and frequencies of the formants, bands of resonant energy characteristic of speech); a sequence of phons (members of a finite alphabet of labels for characteristic sounds, analogous to letters); a sequence of words; a parsed sequence of words reflecting grammatical structure; and finally a semantic data structure representing a sentence (or other utterance) that reflects the meaning behind the sounds.

A class of artificial intelligence programs called expert systems attempt to accomplish tasks by acquiring and incorporating the same knowledge that human experts have. Many attempts to apply artificial intelligence to medicine, government, and other socially significant tasks take the form of expert systems. Even though the emphasis is on knowledge, all the standard ingredients are present.

In careful tests, a number of expert systems have shown performance at levels of quality equivalent to or better than average practicing professionals (for example, average practicing physicians) on the restricted domains over which they operate. Nearly all large corporations and many smaller ones use expert systems. A common application is to provide technical assistance to persons who answer customers' trouble calls. Computer companies use expert systems to assist in configuring components from a parts catalog into a complete system that matches a customer's specifications, a kind of application that has been replicated in other industries tailoring assembled products to customers' needs. Troubleshooting and diagnostic programs are commonplace. Another widespread use of this technology is in software for home computers that assists taxpayers. One important lesson learned from incorporating artificial intelligence software into ongoing practice is that its success depends on many other aspects besides the intrinsic intellectual quality, for example, ease of interaction, integration into existing workflow, and costs.

Expert systems have sparked important insights in reasoning under uncertainty, causal reasoning, reasoning about knowledge, and acceptance of computer systems in the workplace. They illustrate that there is no hard separation between pure and applied artificial intelligence; finding what is required for intelligent action in a complex applied area makes a significant contribution to basic knowledge. See also Expert systems.

In addition to the subject areas mentioned above, significant work in artificial intelligence has been done on puzzles and reasoning tasks, induction and concept identification, symbolic mathematics, theorem proving in formal logic, natural language understanding and generation, vision, robotics, chemistry, biology, engineering analysis, computer-assisted instruction, and computer-program synthesis and verification, to name only the most prominent. As computers become smaller and less expensive, more and more intelligence is built into automobiles, appliances, and other machines, as well as computer software, in everyday use. See also Automata theory; Computer; Control systems; Cybernetics; Digital computer; Intelligent machine; Robotics.


Modern Science: artificial intelligence
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artificial intelligence or AI

The means of duplicating or imitating intelligence in computers, robots, or other devices, which allows them to solve problems, discriminate among objects, and respond to voice command.

Real Estate Dictionary: Artificial Intelligence
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The ability of a computer program to evaluate information and make decisions according to pre-established criteria. This ability is exploited in such applications as Automated Mortgage Underwriting.Example: Excell Mortgage Company, using artificial intelligence, can pre-approve a large volume of mortgage applications in a short period of time. The process is totally computerized and takes applications through use of an Internet site. The computer can interact with applicants and solicit information as required for the underwriting process.

Accounting Dictionary: Artificial Intelligence (AI)
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Umbrella terminology for several main categories of research. They include natural language systems, visual and voice recognition systems, robotic systems, and Expert Systems. Artificial intelligence generally is the attempt to build machines that think, as well as the study of mental faculties through the use of computational models. A reasoning process is involved with self-correction. Significant data are evaluated and relevant relationships, such as the determination of a warranty reserve, uncovered. The computer learns which kind of answers are reasonable and which are not. Artificial intelligence performs complicated strategies that compute the best or worst way to achieve a task or avoid an undesirable result. An example of an application is in tax planning involving tax shelter options given the client's financial position.

Business Encyclopedia: Artificial Intelligence
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Computer systems are becoming commonplace; indeed, they are almost ubiquitous. We find them central to the functioning of most business, governmental, military, environmental, and health-care organizations. They are also a part of many educational and training programs. But these computer systems, while increasingly affecting our lives, are rigid, complex and incapable of rapid change. To help us and our organizations cope with the unpredictable eventualities of an ever-more volatile world, these systems need capabilities that will enable them to adapt readily to change. They need to be intelligent. Our national competitiveness depends increasingly on capacities for accessing, processing, and analyzing information. The computer systems used for such purposes must also be intelligent. Health-care providers require easy access to information systems so they can track health-care delivery and identify the most recent and effective medical treatments for their patients' conditions. Crisis management teams must be able to explore alternative courses of action and support decision making. Educators need systems that adapt to a student's individual needs and abilities. Businesses require flexible manufacturing and software design aids to maintain their leadership position in information technology, and to regain it in manufacturing. (Grosz and Davis, 1994)

The history of artificial intelligence (AI) predates the development of the first computing machines. On a general level, intelligence has been the subject of philosophical study for 2000 years. At the computational level, mathematician Alan Turing constructed a framework for AI during the era of analog computers.

While precise definitions are still the subject of debate, AI may be usefully thought of as the branch of computer science that is concerned with the automation of intelligent behavior. The intent of AI is to develop systems that have the ability to perceive and to learn, to accomplish physical tasks, and to emulate human decision making. AI seeks to design and develop intelligent agents as well as to understand them. Currently, the main fields of research and development include the following:

  1. Natural languages: These studies focus on problems related to natural language interface, machine translation, understanding spoken language, and so forth.
  2. Expert systems: No generalizable solutions are researched, but expertise is used to deal with ill-defined problems and relationships.
  3. Cognition and learning: Investigations are being made into modes of thinking, learning, and problem solving.
  4. Computer vision: Efforts are being made to develop principles and algorithms for machine vision and the interpretation of visual data.
  5. Automatic deduction: This area deals with the resolution of problems, theorem proving, and logic programming.

Foundations

The term "AI" was applied about 1956, giving a formal name to work that had been developing over the previous five or six years. Individuals and organizations have an abiding interest in AI for several important reasons, including the following:

  1. To preserve expertise that might be lost when an acknowledged expert is unavailable.
  2. To create organizational knowledge bases so that others may learn from past problem-solving successes.
  3. To help decision makers be consistent in their evaluation of complex problems.

During its early years AI was dominated by reliance on logic as a means of representing knowledge and on logical inference as the primary mechanism for intelligent reasoning. In the 1990s other paradigms arrived on the scene, some of which had a dramatic impact. Artificial neural networks (ANNs) were motivated by assumptions about how the brain functions— particularly the ideas of massively parallel connections, each of which performs simple computational tasks. Taken together, they represent knowledge as a property of patterns of relationships. Genetic algorithms apply principles of biological evolution to the problems of searching complex solution spaces. The programs do not use logical reasoning either, but evolve toward better and better solutions to complex problems.

Multiagent systems have recently come to the fore of AI research. This emergence has been driven by a recognition that intelligence may be reflected by the collective behaviors of large numbers of very simple interacting members of a community of agents. These agents can be computers, software modules, or virtually any object that can perceive aspects of its environment and proceed in a rational way toward accomplishing a goal.

A variety of disciplines have influenced the development of AI. These include philosophy (logic), mathematics (intractibility, computability, algorithms), psychology (cognition), engineering (computer hardware and software), and linguistics (knowledge representation and natural-language processing).

Long before the development of computers, the notion that thinking was a form of computation motivated the formalization of logic. These efforts continue today. Graph theory provided the architecture for searching a solution space for a problem. Operations research, with its focus on optimization algorithms, used graph theory and other methods to solve complex decision-making problems.

In 1950, Alan Turing proposed what has become known as the Turing Test for defining intelligent behavior. The idea was to specify requirements that a computer would have to exhibit in order to demonstrate intelligence. Briefly, the Turing Test proposes that the computer should be interrogated via telecommunications by a human. Intelligence is exhibited by the computer if the interrogator cannot tell whether there is a human or a computer at the other end. In order to pass the test, a computer would need to have capabilities for natural-language processing, knowledge representation, automated reasoning, and machine learning.

An Evolution of Applications

While computer systems have become commonplace, they are generally rigid, complex, and incapable of rapid change. According to A Report to ARPA on Twenty-First Century Intelligent Systems, for us and our organizations to cope with the unpredictable eventualities of an ever-more volatile world, these systems need capabilities that will enable them to adapt readily to change. The report argues that our national competitiveness depends increasingly on capacities for accessing, processing, and analyzing information (Grosz and Davis, 1994).

One of the early milestones in AI was Newell and Simon's General Problem Solver (GPS). The program was designed to imitate human problem-solving methods. This and other developments such as Logic Theorist and the Geometry Theorem Prover generated enthusiasm for the future of AI. Simon went so far as to assert that in the near-term future the problems that computers could solve would be coextensive with the range of problems to which the human mind has been applied.

Soon difficulties in achieving this objective began to manifest themselves. In scaling up from earlier successes, problems of intractability were encountered. A search for alternative approaches led to attempts to solve typically occurring cases in narrow areas of expertise. This prompted the development of expert systems. A seminal model was MYCIN, developed to diagnose blood infections. Having about 450 rules, MYCIN was able to perform as well as many experts. This and other expert-systems research led to the first commercial expert system, R1, implemented at Digital Equipment Corporation (DEC) to help configure orders for new computer systems. Sub-sequent to R1's implementation, it was estimated to save DEC about $40 million a year.

Other classic systems include the PROSPECTOR program for determining the probable location and type of ore deposits and the INTERNIST program for performing medical diagnosis in internal medicine.

The Future

A Report to ARPA on Twenty-First Century Intelligent Systems identified four types of systems that will have a substantial impact on applications: intelligent simulation, intelligent information resources, intelligent project coaches, and robot teams (Grosz and Davis, 1994).

Intelligent simulations generate realistic simulated worlds that enable extensive affordable training and education that can be made available any time and anywhere. Examples may be hurricane crisis management, exploration of the impacts of different economic theories, tests of products on simulated customers, and technological design—testing features through simulation that would cost millions of dollars to test using an actual prototype.

Intelligent information resources systems (IRSS) will enable easy access to information related to a specific problem. For instance, a rural doctor whose patient presents with a rare condition might use IRSS to help assess different treatments or identify new ones. An educator might find relevant background materials, including information about similar courses taught elsewhere.

Intelligent project coaches (IPC) could function as co-workers, assisting and collaborating with design or operations teams for complex systems. Such systems could remember and recall the rationale of previous decisions and, in times of crisis, explain the methods and reasoning previously used to handle that situation. An IPC for aircraft design, for example, could enhance collaboration by keeping communication flowing among the large, distributed design staff, the program managers, the customer, and the subcontractors.

Robot teams could contribute to manufacturing by operating in a dynamic environment with minimal instrumentation, thus providing the benefits of economies of scale. They could also participate in automating sophisticated laboratory procedures that require sensing, manipulation, planning, and transport.

Conclusion

AI is a young field and faces many complexities. Nonetheless, the Spring 1998 issue of AI Magazine contained articles on the following innovative applications of AI: This is suggestive of the broad potential of AI in the future.

  1. "Case- and Constraint-Based Project Planning for Apartment Construction"
  2. "CREWS–NS: Scheduling Train Crews in The Netherlands"
  3. "An Intelligent System for Case Review and Risk Assessment in Social Services"
  4. "CHEMREG: Using Case-Based Reasoning to Support Health and Safety Compliance in the Chemical Industry"
  5. "MITA: An Information-Extraction Approach to the Analysis of Free-Form Text in Life Insurance Applications"

Bibliography

AI Magazine. (Spring 1998).

Grosz, Barbara, and Davis, Randall, eds. (1994). A Report to ARPA on Twenty-First Century Intelligent Systems.

Luger, George F., and Stubblefield, William A. (1998). Artificial Intelligence: Structures and Strategies for Complex Problem Solving, 3d ed. Reading, MA: Addison-Wesley.

Russell, Stuart J., and Norvig, Peter. (1995). Artificial Intelligence: A Modern Approach. Upper Saddle River, NJ: Prentice-Hall.

[Article by: JAMES V. HANSEN]

Hacker Slang: AI
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Abbreviation for ‘Artificial Intelligence’, so common that the full form is almost never written or spoken among hackers.


Geography Dictionary: artificial intelligence
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The use of computer software in, among others, data collection and processing, analysis, searching for patterns and detecting anomalies, modelling, and problem solving. Applications include genetic algorithms and neural networks.

Philosophy Dictionary: artificial intelligence
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(or AI) The science of making machines that can do the kinds of thing that humans can do. Topics of research have included speech recognition, visual recognition, and the more familiar problem solving and game-playing. Modelling a psychological phenomenon on a computer is a way of showing how the phenomenon is possible in a physical world, and is also a way of bringing out the complexities involved in apparently simple tasks. A central concept in much AI research is that of a representation, with programs designed to construct, adapt, and link representations in the production of intelligent responses. This research has been responsible for a considerable retreat from dogmatic behaviourism, in which the idea of mental manipulations was thought to be unscientific, since it is exactly the storage and manipulation of representations of the world that is demanded in the problems AI approaches. Strong AI is the philosophical thesis that appropriately programmed computers have minds in exactly the same sense that we do. Weak AI is the methodological belief that the best way to explore the mind is to proceed as if this were true, without commenting on the legacies of dualism that lead to discomfort with the strong thesis. See also Chinese room, connectionism, frame problem, Turing test.

US History Encyclopedia: Artificial Intelligence
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Artificial Intelligence, a branch of computer science that seeks to create a computer system capable of sensing the world around it, understanding conversations, learning, reasoning, and reaching decisions, just as would a human. In 1950 the pioneering British mathematician Alan Turing proposed a test for artificial intelligence in which a human subject tries to talk with an unseen conversant. The tester sends questions to the machine via teletype and reads its answers; if the subject cannot discern whether the conversation is being held with another person or a machine, then the machine is deemed to have artificial intelligence. No machine has come close to passing this test, and it is unlikely that one will in the near future. Researchers, however, have made progress on specific pieces of the artificial intelligence puzzle, and some of their work has had tangible benefits.

One area of progress is the field of expert systems, or computer systems designed to reproduce the knowledge base and decision-making techniques used by experts in a given field. Such a system can train workers and assist in decision making. MYCIN, a program developed in 1976 at Stanford University, suggests possible diagnoses for patients with infectious blood diseases, proposes treatments, and explains its "reasoning" in English. Corporations have used such systems to reduce the labor costs involved in repetitive calculations. A system used by American Express since November 1988 to advise when to deny credit to a customer saves the company millions of dollars annually.

A second area of artificial intelligence research is the field of artificial perception, or computer vision. Computer vision is the ability to recognize patterns in an image and to separate objects from background as quickly as the human brain. In the 1990s military technology initially developed to analyze spy-satellite images found its way into commercial applications, including monitors for assembly lines, digital cameras, and automotive imaging systems. Another pursuit in artificial intelligence research is natural language processing, the ability to interpret and generate human languages. In this area, as in others related to artificial intelligence research, commercial applications have been delayed as improvements in hardware—the computing power of the machines themselves—have not kept pace with the increasing complexity of software.

The field of neural networks seeks to reproduce the architecture of the brain—billions of connected nerve cells—by joining a large number of computer processors through a technique known as parallel processing. Fuzzy systems is a subfield of artificial intelligence research based on the assumption that the world encountered by humans is fraught with approximate, rather than precise, information. Interest in the field has been particularly strong in Japan, where fuzzy systems have been used in disparate applications, from operating subway cars to guiding the sale of securities. Some theorists argue that the technical obstacles to artificial intelligence, while large, are not insurmountable. A number of computer experts, philosophers, and futurists have speculated on the ethical and spiritual challenges facing society when artificially intelligent machines begin to mimic human personality traits, including memory, emotion, and consciousness.

Bibliography

Kurzweil, Ray. The Age of Spiritual Machines. New York: Viking, 1999.

Partridge, Derek. A New Guide to Artificial Intelligence. Norwood, N.J.: Ablex, 1991.

Shapiro, Stuart C., ed. Encyclopedia of Artificial Intelligence. 2d ed. New York: Wiley, 1992.

Turbam, Efraim. Expert Systems and Applied Artificial Intelligence. New York: MacMillan, 1992.

—Vincent Kiernan/A. R.

 
Columbia Encyclopedia: artificial intelligence
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artificial intelligence (AI), the use of computers to model the behavioral aspects of human reasoning and learning. Research in AI is concentrated in some half-dozen areas. In problem solving, one must proceed from a beginning (the initial state) to the end (the goal state) via a limited number of steps; AI here involves an attempt to model the reasoning process in solving a problem, such as the proof of a theorem in Euclidean geometry. In game theory (see games, theory of), the computer must choose among a number of possible "next" moves to select the one that optimizes its probability of winning; this type of choice is analogous to that of a chess player selecting the next move in response to an opponent's move. In pattern recognition, shapes, forms, or configurations of data must be identified and isolated from a larger group; the process here is similar to that used by a doctor in classifying medical problems on the basis of symptoms. Natural language processing is an analysis of current or colloquial language usage without the sometimes misleading effect of formal grammars; it is an attempt to model the learning process of a translator faced with the phrase "throw mama from the train a kiss." Cybernetics is the analysis of the communication and control processes of biological organisms and their relationship to mechanical and electrical systems; this study could ultimately lead to the development of "thinking" robots (see robotics). Machine learning occurs when a computer improves its performance of a task on the basis of its programmed application of AI principles to its past performance of that task.

In the public eye advances in chess-playing computer programs have become symbolic of progress in AI. In 1948 British mathematician Alan Turing developed a chess algorithm for use with calculating machines-it lost to an amateur player in the one game that it played. Ten years later American mathematician Claude Shannon articulated two chess-playing algorithms: brute force, in which all possible moves and their consequences are calculated as far into the future as possible; and selective mode, in which only the most promising moves and their more immediate consequences are evaluated. In 1988 Hitech, a program developed at Carnegie-Mellon Univ., defeated former U.S. champion Arnold Denker in a four-game match, becoming the first computer to defeat a grandmaster. A year later, Gary Kasparov, the reigning world champion, bested Deep Thought, a program developed by the IBM Corp., in a two-game exhibition. In 1990 the German computer Mephisto-Portrose became the first program to defeat a former world champion; while playing an exhibition of 24 simultaneous games, Anatoly Karpov bested 23 human opponents but lost to the computer. Kasparov in 1996 became the first reigning world champion to lose to a computer in a game played with regulation time controls; the Deep Blue computer, developed by the IBM Corp., won the first game of the match, lost the second, drew the third and fourth, and lost the fifth and sixth. Deep Blue used the brute force approach, evaluating more than 100 billion chess positions each turn while looking six moves ahead; it coupled this with the most efficient chess evaluation software yet developed and an extensive library of chess games it could analyze as part of the decision process. Subsequent matches between Vladimir Kramnik and Deep Fritz (2002, 2006) and Kasparov and Deep Junior (2003) have resulted in two ties and a win for the programs. Unlike Deep Blue, which was a specially designed computer, these more recent computer challengers are chess programs that run on powerful personal computers. Such programs have become an important tool in chess, and are used by chess masters to analyze games and experiment with new moves.

Bibliography

See D. Freedman, Brainmakers: How Scientists Are Moving Beyond Computers to Create a Rival to the Human Brain (1994); D. Gelernter, The Muse in the Machine: Computerizing the Poetry of Human Thought (1994).


World of the Mind: artificial intelligence
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(AI)

Igor Alexander
Margaret Boden
Ron Chrisley

Igor Alexander

The process of designing machines with abilities modelled on human thought. While this mostly involves writing computer programs with human-like characteristics, it has implications for the design of robots and raises philosophical questions about machine–human comparisons.

1. Origins and ambitions
2. Knowledge, logic, and learning
3. Evolution, agents, and brain–mind comparisons

1. Origins and ambitions

Artificial intelligence may be said to have begun in 1950 when Claude Shannon of the Bell Telephone Laboratories in the United States wrote an ingenious program that was to be the forerunner of all chess-playing machines. This work drastically changed the accepted perception of stored-program computers which, since their birth in 1947, had been seen just as automatic calculating machines. Shannon's program added the promise of automated intelligent action to the actuality of automated calculation.

In Shannon's program the programmer stores in the computer the value of important features of board positions. A 'checkmate' being a winning position would have the highest value and the capture of more or less important pieces would be given relatively lower values. So, say that the computer is to take the next move, it would (by being programmed to follow the rules of the game) work out all the possible moves that the opponent might take. It could then work out which moves are available to itself at the next playing period and so on for several periods ahead in the search for a winning path through this 'tree' of possibilities. Sadly, the amount of computation needed to evaluate board positions grows prodigiously the further ahead the computer is meant to look. This process of searching through a large number of options became central in AI programs throughout the 1960s and the early 1970s. Other intelligent tasks besides game playing came under scrutiny: general problem solving, the control of robots, computer vision, speech processing, and the understanding of natural language. Solving general problems requires searches that are similar to those in the playing of board games. For example, to work out how to get from an address in London to the Artificial Intelligence laboratory at the University of Edinburgh, the problem can be represented as a search among subgoals (e.g. get to Edinburgh airport) and the use of 'means' such as airlines, taxis, or railways. The paths through the scheme are evaluated in terms of the reduction of cost and/or the reduction of time to the user. Robot control is similar. The physical rearrangement of objects in a space has to follow a strategy that involves the most efficient path between a current arrangement and the desired one, via several intermediate ones.

Computer vision and the recognition of speech required the programmer to determine that some features of the sensory input generated as signals from a video camera or a microphone are important. For example, for face recognition, the program has to identify the central positions of eyes, nose, and mouth and then measure the size of these objects and the distances between them. These measurements for a collection of faces are stored in a database, each together with the identity of the face. So were a face in the known set to be presented to the camera, finding the closest fit to the measurements stored in the database could identify it. Similarly the features of voices and the sound of words could be stored in databases for the purpose of eventual recognition.

Perhaps the most ambitious target for AI designers was the extraction of meaning from language. This goes beyond speech recognition and sentences could be presented in their written form. The difficulty is for the programmer to find rules that distinguish between sentences such as 'he broke the window with a rock' and 'he broke the window with a curtain'. This required a storage of long lists of words indicating whether they were instruments (rock) or embellishments (curtain) so that the correct meaning could be ascribed to them as they appear in a sentence.

However, early enthusiasm that AI computers could perform tasks comparable to those of humans were to be curtailed by the mid-1970s when poignant shortcomings emerged because the techniques used suffered from serious limitations. In 1971, the British mathematician Sir James Lighthill advised the major science-funding agency in the United Kingdom that AI was suffering from something he called the 'combinatorial explosion' which has been mentioned above in the chess-playing example. Every time the computer needs to look a further step ahead, the number of moves to be evaluated is that of the previous level multiplied by a large amount. In 1980, US philosopher John Searle levelled a second criticism at those who had claimed that they had enabled computers to understand natural language. Through his celebrated 'Chinese Room' argument he pointed out that the computer, by stubbornly following rules, was like a non-Chinese speaker using a massive set of rules to match questions expressed in Chinese symbols about a story also written in Chinese symbols. Given the time to examine many rules, the non-Chinese speaker could find the correct answers in Chinese symbols, without there being any understanding in the procedure. According to Searle, understanding requires a feeling of 'aboutness' for words and phrases which computers do not have. Also a third difficulty began to emerge: artificial intelligence depended too heavily on programmers having to work out in detail how to specify intelligent tasks. In pattern recognition, for example, ideas about how to recognize faces, scenes, and sounds turned out to be inadequate, particularly with respect to human performance.

2. Knowledge, logic, and learning

These censures had a healthy effect on AI. The 1980s saw a maturing of the field through the appearance of new methodologies dubbed knowledge-based systems, expert systems, and artificial neural networks (or connectionism). Effort in knowledge-based systems used formal logic to greater effect than before. The application of the logical rules of inheritance and resolution made more efficient use of knowledge stored in databases. For example, 'Socrates is a man' and 'All men are mortals' could lead to the knowledge that 'Socrates is mortal' by logical inference rather than by explicit storage, thus easing the problem of holding vast amounts of data in databases.

Expert systems was the name given to applications of AI which sought to transfer human expertise into knowledge bases so as to make such knowledge widely available to non-experts. This employed a 'knowledge engineer' who elicited knowledge from the expert and structured it appropriately for inclusion in a database. Facts and rules were clearly distinguished to enable them to be logically manipulated. Typical applications are in engineering design and fault finding, medical diagnosis and advice, and financial advice.

The aim of artificial neural network studies is to simulate mechanisms which, in the brain, are responsible for mind and intelligence. An artificial neuron learns to respond or not to respond ('fire' or not) to a pattern of signals from other neurons to which it is connected. A multi-layered network of such devices can learn (by automatically adjusting the strengths of the interconnections in the network) to classify patterns by learning to extract increasingly telling features of such patterns as data progresses through the layers. The presence of learning overcomes some of the difficulties previously due to the programmer having to decide exactly how to recognize complex visual and speech patterns. Also, a totally different class of artificial neural networks may be used to store and retrieve knowledge. Known as dynamic neural networks, such systems rely on the inputs of neurons being connected to the outputs of other neurons. This allows the net to be taught to keep a pattern of firing activity stable at its outputs. It can also learn to store sequences of patterns. These stable states or sequences are the stored knowledge of the network which may be retrieved in response to some starting state or a set of inputs also connected to the neurons in the net. So in terms of pattern recognition, not only can these networks learn to label patterns, but also 'know' what things look like in terms of neural firing patterns.

3. Evolution, agents, and brain–mind comparisons

Despite the above two major phases in the history of artificial intelligence, the subject is still developing, particularly in three domains: new techniques for creating intelligent programs, using computers to understand the complexities of brain and mind, and, finally, contributing to philosophical debate.The techniques added to the AI repertoire are evolutionary programming, artificial life, and intelligent software agents. Evolutionary programming borrows from human genetic development in the sense that some variants of a program may have a better performance than others. It is possible to represent the design parameters of a system as a sequence of values resembling a chromosome. An evolutionary program tests a range of systems against a performance criterion (the fitness function). It chooses the chromosomes of various system pairs that have good fitness behaviour to combine them and create a new generation of systems. This gives rise to increasingly more able systems even to the extent that their design holds surprises for expert designers. Such mimicking of a major mechanism of biological life leads to the concept of artificial life. For example, UK entrepreneur Steve Grand includes in his 'Creatures' game simulations of some biochemical processes to produce societies of virtual (computer-bound but observable) creatures with realistic life cycles and social interactions. This allows the game player to take care of a virtual creature in a game that gets close to the problems of survival in real life. The more general study of intelligent software agents takes virtual creatures into domains where they could perform useful tasks such as finding desired data on the internet. They are little programs that store the needs of a user and trawl the World Wide Web for this desired information. Also a burgeoning interest is in societies of such agents to discover how cooperation between them may lead to the solution of problems in distributed domains. Translated to multiple interacting robots, agent studies lead to a better understanding of flocking behaviour and the way that this achieves goals for the flock.

A better understanding of the brain flows from the study of artificial neural networks (ANNs). Accepting that the brain is the most complex machine in existence, ANNs are now being used to isolate some of its structural features in order to begin to understand their interactions. For example, it has been possible to suggest a theoretical basis for understanding dyslexia, visual hallucinations under the influence of drugs, and the nature of visual awareness in general. The latter and grander ambition feeds a philosophical debate on whether machines could think like humans that has paralleled AI for its entire existence. The question was first raised by British mathematician Alan Turing in 1950. His celebrated test was based on the external behaviour of an AI machine and its ability to fool a human interlocutor into thinking that it too was human. This debate has now moved on to discuss whether a machine could ever be conscious. The main arguments against this come from a belief that consciousness, being a 'first-person' phenomenon, cannot be approached from the 'third-person' position which is inherent in all man-made designs. The contrary arguments are put by those who feel that by simulating with great care the function and structure of the brain it will be possible both to understand the mechanisms of consciousness and to transfer them to a machine.
    Bibliography
  • Aleksander, I. (2001). How to Build a Mind: Machines with Imagination.
  • — —  and Morton, B. H. (1993). Neurons and Symbols.
  • Boden, M. A. (ed.) (1996). Artificial Intelligence (2nd edn.).
  • Crick, F. (1994). The Astonishing Hypothesis.
  • Grand, S. (2000). Creation: Life and How to Make it.
  • Searle, J. R. (1980). 'Minds brains and programs'. Behavioural and Brain Sciences, 3.
  • Shannon, C. E. (1950). 'Programming a computer for playing chess'. Phil. Mag. 4.
  • Tecuci, G. (1998). Building Intelligent Agents.
  • Turing, A. M. (1950). 'Computing machinery and intelligence'. Mind, 59.

Margaret Boden

The science of making machines do the sorts of things that are done by human minds. Such things include holding a conversation, answering questions sensibly on the basis of incomplete knowledge, assembling another machine from its components given the blueprint, learning how to do things better, playing chess, writing or translating stories, understanding analogies, neurotically repressing knowledge that is too threatening to admit consciously, learning to classify visual or auditory patterns, composing a poem or a sonata, and recognizing the various things seen in a room — even an untidy and ill-lit room. AI helps one to realize how enormous is the background knowledge and thinking (computational) power needed to do even these everyday things.

The 'machines' in question are typically digital computers, but AI is not the study of computers. Rather, it is the study of intelligence in thought and action. Computers are its tools, because its theories are expressed as computer programs which are tested by being run on a machine. Some AI programs are lists of symbolic rules (if this is the case then do that, else do another ...). Others specify 'brainlike' networks made of many simple, interconnected, computational units. These types of AI are called traditional (or classical) and connectionist, respectively. They have differing, and largely complementary, strengths and weaknesses.

Other theories of intelligence are expressed verbally, either as psychological theories of thinking and behaviour, or as philosophical arguments about the nature of knowledge and purpose and the relation of mind to body (the mind–body problem). Because it approaches the same subject matter in different ways, AI is relevant to psychology and the philosophy of mind.

Similarly, attempts to write programs that can interpret the two-dimensional image from a TV camera in terms of the three-dimensional objects in the real world (or which can recognize photographs or drawings as representations of solid objects) help make explicit the range and subtlety of knowledge and unconscious inference that underlie our introspectively 'simple' experiences of seeing. Much of this knowledge is tacit (and largely innate) knowledge about the ways in which, given the laws of optics, physical surfaces of various kinds can give rise to specific visual images on a retina (or camera). Highly complex computational processes are needed to infer the nature of the physical object (or of its surfaces), on the basis of the two-dimensional image.

If we think of an AI system as a picture of a part of the mind, we must realize that a functioning program is more like a film of the mind than a portrait of it. Programming one's hunches about how the mind works is helpful in two ways. First, it enables one to express richly structured psychological theories in a rigorous, and testable, fashion. Second, it forces one to suggest specific hypotheses about precisely how a psychological change can come about. Even if (as in connectionist systems: see below) one only provides a learning rule, rather than telling the AI system precisely what to learn, that rule has to be rigorously expressed; a different rule will lead to different performance.

In general, it is easier to model logical and mathematical reasoning (which people find difficult) than to simulate high-level perception or language understanding (which we do more or less effortlessly). Significant progress has been made, for instance, in recognizing keywords and grammatical structure, and AI programs can even come up with respectable, though juvenile, puns and jokes. But many sentences, and jokes, assume a large amount of world knowledge, including culture-specific knowledge about sport, fashion, politics, soap operas ... the list is literally endless. There is little or no likelihood than an actual AI system could use language as well as we can, because it is too difficult to provide, and to structure, the relevant knowledge (much of it is tacit, and very difficult to bring into consciousness). But this need not matter, if all we want is a psychological theory that explains how these human capacities are possible. Similarly, research in AI has shown that highly complex, and typically unconscious, computational processes are needed to infer the nature of physical objects from the image reaching the retina/camera.

Traditional philosophical puzzles connected with the mind–body problem can often be illuminated by AI, because modelling a psychological phenomenon on a computer is a way of showing that and how it is possible for that phenomenon to arise in a physical system. For instance, people often feel that only a spiritual being (as opposed to a bodily one) could have purposes and try to achieve them, and the problem then arises of how the spiritual being, or mind, can possibly tell the body what to do, so that the body's hand can try to achieve the mind's purpose of, say, picking a daisy. It is relevant to ask whether, and how, a program can enable a machine to show the characteristic features of purpose. Is its behaviour guided by its idea of a future state? Is that idea sometimes illusory or mistaken (so that the 'daisy' is made of plastic, or is really a buttercup)? Does it symbolize what it is doing in terms of goals and subgoals (so that the picking of the daisy may be subordinate to the goal of stocking the classroom nature table)? Does it use this representation to help plan its actions (so that the daisies on the path outside the sweetshop are picked, rather than those by the petrol station)? Does it vary its means–end activities so as to achieve its goal in different circumstances (so that buttercups will do for the nature table if all the daisies have died)? Does it learn how to do so better (so that daisies for a daisy-chain are picked with long stalks)? Does it judge which purposes are the more important, or easier to achieve, and behave accordingly (if necessary, abandoning the daisy picking when a swarm of bees appears with an equally strong interest in the daisies)? Questions like these, asked with specific examples of functioning AI systems in mind, cannot fail to clarify the concept of purpose. Likewise, philosophical problems about the nature and criteria of knowledge can be clarified by reference to programs that process and use knowledge, so that AI is relevant to epistemology.

AI is concerned with mental processing in general, not just with mathematics and logical deduction. It includes computer models of perception, thought, motivation, and emotion. Emotion, for instance, is not just a feeling: emotions are scheduling mechanisms that have evolved to enable finite creatures with many potentially conflicting motives to choose what to do, when. (No matter how hungry one is, one had better stop eating and run away if faced by a tiger.) So a complex animal is going to need some form of computational interrupt, and some way of 'stacking' and realerting those unfulfilled intentions that shouldn't, or needn't, be abandoned. In human language users, motivational–emotional processing includes deliberately thought–out plans and contingency plans, and anticipation of possible outcomes from the various actions being considered.

One important variety of AI is connectionism, or artificial neural networks. Very few connectionist systems are implemented in fundamentally connectionist hardware. Most are simulated (as virtual machines) in digital computers. That is, the program does not list a sequence of symbolic rules but simulates many interconnected 'neurons', each of which does only very simple things. Connectionism enables a type of learning wherein the 'weights' on individual units in the network are gradually altered until recognition errors are minimized. Unlike learning in classical AI, the unfamiliar pattern need not be specifically described to the system before it can be learnt; however, it must be describable in the 'vocabulary' used for the system's input. Connectionism allows that beliefs and perceptions may be grounded on partly inconsistent evidence, and that most concepts are not strictly defined in terms of necessary and sufficient conditions. Many connectionist systems represent a concept as a pattern of activity across the whole network; the units eventually settle into a state of maximum, though not necessarily perfect, equilibrium. Connectionism is a powerful way of implementing pattern recognition and the 'intuitive' association of ideas. But it is very limited for implementing hierarchical structure of sequential processes, such as are involved in deliberate planning. Some AI research aims to develop 'hybrid' systems combining the strengths of traditional and connectionist AI. Certainly, the full range of adult human psychology cannot be captured by either of these approaches alone.

The main areas of AI include natural language understanding (see speech recognition by machine), machine vision (see pattern recognition), problem solving and game playing (see computer chess), robotics, automatic programming, and the development of programming languages. Among the practical applications most recently developed or currently being developed are medical diagnosis and treatment (where a program with specialist knowledge of, say, bacterial infections answers the questions of and elicits further relevant information from a general practitioner who is uncertain which drug to prescribe in a given case); prediction of share prices on the stock exchange; assessment of creditworthiness; speech analysis and speech synthesis; the composition of music, including jazz improvisation; location of mineral deposits, such as gold or oil; continuous route planning for car drivers; programs for playing chess, bridge, or Go, etc.; teaching some subject such as geography, or electronics, to students with differing degrees of understanding of the material to be explored; the automatic assembly of factory-made items, where the parts may have to be inspected first for various types of flaw and where they need not be accurately positioned at a precise point in the assembly line, as is needed for the automation in widespread use today; and the design of complex systems, whether electrical circuits or living spaces or some other, taking into account factors that may interact with each other in complicated ways (so that a mere 'checklist' program would not be adequate to solve the design problem).

An area closely related to AI is artificial life (A-life). This is a form of mathematical biology. It uses computational concepts and models to study (co-)evolution and self-organization, both of which apply to life in general, and to explain specific aspects of living things — such as navigation in insects or flocking in birds. (The dinosaurs in Jurassic Park were computer generated using simple A-life algorithms.) One example of A-life is evolutionary robotics, where the robot's neural network 'brain' and/or sensorimotor anatomy is not designed by hand but evolved over thousands of generations. The programs make random changes in their own rules, and a fitness function is applied, either automatically or manually, to select the best from the resulting examples; these are then used to breed the next generation. Some A-life scientists, but not all, accept 'strong' A-life: the view that a virtual creature, defined by computer software, could be genuinely alive. And some believe that A-life could help us to find an agreed definition of what 'life' is. All the minds we know of are embodied in living things, and some people argue that only a living thing could have a mind, or be intelligent. If that is right, then success in AI cannot be achieved without success in A-life. (In both cases, however, 'success' might be interpreted either as merely showing mindlike/lifelike behaviour or as being genuinely intelligent/alive.)

The social implications of AI are various. As with all technologies, there are potential applications which may prove bad, good, or ambiguous in human terms. A competent medical diagnosis program could be very useful, whereas a competent military application would be horrific for those at the receiving end, and a complex data-handling system could be well or ill used in many ways by individuals or governments. Then there is the question of what general implication AI will be seen to have for the commonly held 'image of man'. If it is interpreted by the public as implying that people are 'nothing but clockwork, really', then the indirect effects on self-esteem and social relations could be destructive of many of our most deeply held values. But it could (and should) be interpreted in a radically different and less dehumanizing way, as showing how it is possible for material systems (which, according to the biologist, we are) to possess such characteristic features of human psychology as subjectivity, purpose, freedom, and choice. The central theoretical concept in AI is representation, and AI workers ask how a (programmed) system constructs, adapts, and uses its inner representations in interpreting and changing its world. On this view, a programmed computer may be thought of as a subjective system (subject to illusion and error much as we are) functioning by way of its idiosyncratic view of the world. By analogy, then, it is no longer scientifically disreputable, as it has been thought to be for so long, to describe people in these radically subjective terms also. AI can therefore counteract the dehumanizing influence of the natural sciences that has been part of the mechanization of our world picture since the scientific revolution of the 16th and 17th centuries.
    Bibliography
  • Boden, M. A. (1987). Artificial Intelligence and Natural Man (2nd rev. edn.).
  • — —  (1990). The Creative Mind.
  • — —  (ed.) (1990). The Philosophy of Artificial Intelligence.
  • Clark, A. J. (1990). Associative Engines.
  • Cope, D. (2001). Virtual Music.
  • Feigenbaum, E. A., and Feldman, J. (eds.) (1963). Computers and Thought.
  • Jullam, J. (ed.) (1995). Hybrid Problems, Hybrid Solutions.
  • Levy, S. J. (1992). Artificial Life.
  • McClelland, J. L., and Rumelhart, D. E. (eds.) (1986). Parallel Distributed Processing: Explorations in the Microstructure of Cognition, 2 vols.
  • Marr, D. A. (1980). Vision.
  • Minsky, M. L. (1985). The Society of Mind.
  • Whitby, B. (1996). Reflections on Artificial Intelligence.
  • Winograd, T. (1972). Understanding Natural Language.

Ron Chrisley

Researchers in artificial intelligence attempt to design and create artefacts which have, or at least appear to have, mental properties: not just intelligences, but also perception, action, emotion, creativity, and consciousness.

1. Recent developments
2. The relevance of AI to understanding the mind

1. Recent developments

Since the mid-1980s, there has been sustained development of the core ideas of artificial intelligence, e.g. representation, planning, reasoning, natural language processing, machine learning, and perception. In addition, various subfields have emerged, such as research into agents (autonomous, independent systems, whether in hardware or software), distributed or multi-agent systems, coping with uncertainty, affective computing/models of emotion, and ontologies (systems of representing various kinds of entities in the world — achievements that, while new advances, are conceptually and methodologically continuous with the field of artificial intelligence as envisaged at the time of its modern genesis: the Dartmouth conference of 1956.

However, a substantial and growing proportion of research into artificial intelligence, while often building on the foundations just mentioned, has shifted its emphasis. This change in emphasis, inasmuch as it constitutes a conceptual break with those foundations, promises to make substantial contributions to our understanding and concepts of mind. It remains to be seen whether these contributions will replace or (as may seem more likely) merely supplement those already provided by what might be termed the 'Dartmouth approach' and its direct successors.

The new developments, which have their roots in the cybernetics work of the 1940s and 1950s as much as, if not more than, they do in mainstream AI, can be divided into two broad areas: adaptive systems and embodied/situated approaches. This is not to say that they are exclusive; much promising work, such as the field of evolutionary robotics, combines elements of both areas.Adaptive systems The 1980s saw a rise in the popularity of both neural networks (sometimes also called connectionist models) and genetic algorithms. Neural networks are systems comprising thousands or more of (usually simulated) simple processing units; the computational result of the network is determined by the input and the connections between the units, which may vary their ability to pass a signal from one unit to the next. Nearly all of these networks are adaptive in that they can learn. Learning typically consists in finding a set of connections that will make the network give the right output for each input in a given training set.

Genetic algorithms produce systems that perform well on some tasks by emulating natural selection. An initial random population of systems (whose properties are determined by a few parameters) are ranked according to their performance on the task; only the best performers are retained (selection). A new population is created by mutating or combining the parameters of the winners (reproduction and variation). Then the cycle repeats.

Although the importance of learning had been acknowledged since the earliest days of AI, these two approaches, despite their differences, had a common effect of making adaptivity absolutely central to AI.

While machine learning assumed conceptual building blocks with which to build learned structures, neural networks allowed for subsymbolic learning: the acquisition of the conceptual 'blocks' themselves, in a way that cannot be understood in terms of logical inference, and that may involve a continuous change of parameters, rather than discrete steps of accepting or rejecting sentences as being true or false. By allowing systems to construct their own 'take' on the world, AI researchers were able to begin overcoming the obstacles that were thrown up when they attempted to put adult human conceptual structures into systems that were quite different from us.

Standard AI methodology for giving some problem-solving capability to a machine had at first been: think about how you would solve the problem, write down the steps of your solution in a computer language, give the program to the machine to run. This was refined and extended in several ways. For example, the knowledge engineering approach asks an expert about the important facts of the domain, translates these into sentences in a knowledge representation language, gives these sentences to the machine, and lets the machine perform various forms of reasoning by manipulating these sentences. But it remained the case that, in these extensions of the basic AI methodology, the machine was limited to using the programmer's or expert's way of representing the world. By using adaptive approaches like artificial evolution, AI systems are no longer limited to solutions that humans can conceptualize — in fact the evolved or learned solutions are often inscrutable. Our concepts and intuitions might not be of much use in getting a six-legged robot to walk; our introspection might even lead us astray concerning the workings of our own minds. For both reasons, genetic algorithms are an impressive addition to the AI methodological toolbox.

However, along with these advantages come limitations. There is a general consensus that the simple, incremental methods of the adaptive approaches, while giving relatively good results for tasks closely related to perception and action, cannot scale up to tasks that require sophisticated, abstract, and conceptual abilities. Give a system some symbols and some rules for combining them, and it can potentially produce an infinite number of well-formed symbol structures — a feature that parallels human competence. But a neural network that has learned to produce a set of complex structures will usually fail to generalize this into a systematic competence to construct an infinite number of novel combinations. Genetic algorithms have similar limitations to their 'scaling up'. But even if these obstacles are overcome, and systems with advanced forms of mentality are created by these means, the very fact that we shall not have imposed our own concepts on them may render their behaviour itself inexplicable. What we do not need is another mind we cannot understand! With respect to AI's goal of adding to our understanding of the mind, adaptive (especially evolved) systems may be as much a part of the problem as a part of the solution (see section 2). And technological AI is also hindered if the systems it produces cannot be understood well enough to be trusted for use in the real world.Embodied and situated systems Embodied and situated approaches to AI investigate the role that the body and its sensorimotor processes (as opposed to symbols or representations on their own) can and do play in intelligent behaviour. Intelligence is viewed as the capacity for real-time, situated activity, typically inseparable from and often fully interleaved with perception and action. Further, it is by having a body that a system is situated in the world, and can thus exploit its relations to things in the world in order to perform tasks that might previously have been thought to require the manipulation of internal representations or data structures. For an example of embodied intelligence, suppose a child sees something of interest in front of him, points to it, turns his head back to get his mother's attention, and then returns his gaze to the front. He does not need to have some internal representation that stores the eye, neck, torso, etc. positions necessary to gaze on the item of interest; the child's arm itself will indicate where the child should look; the child's exploitation of his own embodiment obviates the need for him to store and access a complex inner symbolic structure. For an example of situated problem solving, suppose another child is solving a jigsaw puzzle. The child does not need to look at each piece intently, forming an internal representation of its shape, and then when all pieces have been examined, close her eyes and solve the puzzle in her head! Rather, the child can manipulate the pieces themselves, making it possible for her to perceive whether two of them will fit together. If nature has sometimes used these alternatives to complex inner symbol processing, then AI can (perhaps must) as well.

These are a cluster of other AI approaches that, while properly distinct from embodiment and situatedness, are nevertheless their natural allies.

(i) Some researchers have found it useful to turn away from discontinuous, atemporal, logic-based formalisms and instead use the continuous mathematics of change offered by dynamical systems theory as a way to characterize and design intelligent systems.
(ii) Some researchers have claimed that AI should, whenever possible, build systems working in the real world, with, for example, real cameras receiving real light, instead of relying on ray-traced simulations of light; a real-world AI system might exploit aspects of a situation we are not aware of and which we therefore do not incorporate in our simulations.
(iii) Some insist that AI should concentrate on building complete working systems, with simple but functioning and interacting perceptual, reasoning, learning, action, etc. systems, rather than working on developed yet isolated competences, as has been the method in the past.

Architectures A change of emphasis common to both the more and less traditional varieties of AI is a move away from a search for specific algorithms and representations, and toward a search for the architectures that support various forms of mentality. An architecture specifies how the various components of a system, which may in fact be representations or algorithms, fit together and interact in order to yield a working system. Thus, an architecture-based approach can render irrelevant many debates over which algorithm or representational scheme is 'best'.

2. The relevance of AI to understanding the mind

Why do AI? Of course, there are technological reasons. But are there scientific reasons? Can AI illuminate our understanding of the mind? The acts involved in bringing natural intelligences into the world do not (usually!) confer any insight into the nature of intelligence; why should one think the acts involved in creating artificial intelligence would be any more enlightening?

For one thing, not all AI eschews design to the extent that the genetic algorithm approach (above) does; most approaches involve the designer understanding, in advance, at least roughly how the constructed system works. AI need not got so far as to say 'if you can't build it, you can't understand it', but building an intelligence might at least help.

It is sometimes argued in return that the kind of systems that AI is likely to produce will be so different from naturally intelligent systems (e.g. they are not alive) that

(i) they will not shed much light on natural intelligence and
(ii) they will not be able to reach the heights that natural intelligence does.

Surely, these people conclude, if one is interested in intelligence and the mind, one should instead do neuroscience, or at least psychology?

One can defend the AI methodology for understanding natural intelligence by appealing to the history of understanding flight. Attempts both to achieve artificial flight and to understand natural flight failed as long as scientists tried to reproduce too closely what they saw in nature. It wasn't until scientists looked at simple, synthetic systems (such as Bernoulli's aerofoil), which could be arbitrarily manipulated and studied, that the general aerodynamic principles that underlie both artificial and natural flight could be identified. So also it may be that it is only by creating and interacting with simple (but increasingly complex) artificial systems that we will be able to uncover the general principles that will allow us both to construct artificial intelligence and understand natural intelligence.

(Published 2004)
    Bibliography
  • Bishop, C. M. (1995). Neural Networks for Pattern Recognition.
  • Brooks, R. (1991). 'Intelligence without representation'. Artificial Intelligence, 47.
  • Chrisley, R. (ed.) (2000). Artificial Intelligence: Critical Concepts.
  • Clark, A. (1997). Being There: Putting Brain, Body and World Together Again.
  • Franklin, S. (1995). Artificial Minds.
  • Goldberg, D. E. (1989). Genetic Algorithms in Search, Optimization, and Machine Learning.
  • Nilsson, N. (1998). Artificial Intelligence: A New Synthesis.
  • Sharples, M., Hogg, D., Hutchison, C., Torrance, S., and Young, D. (1998). Computers and Thought: A Practical Introduction to Artificial Intelligence.
  • Sloman, A. (1997). 'What sort of architecture is required for a human-like agent?' In Wooldridge, M., and Rao, A. (eds.), Foundations of Rational Agency.
  • Smith, B. C. (1991). 'The owl and the electric encyclopedia'. Artificial Intelligence.


Wikipedia: Artificial intelligence
Top

Artificial intelligence (AI) is the intelligence of machines and the branch of computer science which aims to create it. Textbooks define the field as "the study and design of intelligent agents,"[1] where an intelligent agent is a system that perceives its environment and takes actions which maximize its chances of success.[2] John McCarthy, who coined the term in 1956,[3] defines it as "the science and engineering of making intelligent machines."[4]

The field was founded on the claim that a central property of humans, intelligence—the sapience of Homo sapiens—can be so precisely described that it can be simulated by a machine.[5] This raises philosophical issues about the nature of the mind and limits of scientific hubris, issues which have been addressed by myth, fiction and philosophy since antiquity.[6] Artificial intelligence has been the subject of optimism,[7] but has also suffered setbacks[8] and, today, has become an essential part of the technology industry, providing the heavy lifting for many of the most difficult problems in computer science.[9]

AI research is highly technical and specialized, deeply divided into subfields that often fail to communicate with each other.[10] Subfields have grown up around particular institutions, the work of individual researchers, the solution of specific problems, longstanding differences of opinion about how AI should be done and the application of widely differing tools. The central problems of AI include such traits as reasoning, knowledge, planning, learning, communication, perception and the ability to move and manipulate objects.[11] General intelligence (or "strong AI") is still a long-term goal of (some) research.[12]

Contents

History

Thinking machines and artificial beings appear in Greek myths, such as Talos of Crete, the golden robots of Hephaestus and Pygmalion's Galatea.[13] Human likenesses believed to have intelligence were built in every major civilization: animated statues were worshipped in Egypt and Greece[14] and humanoid automatons were built by Yan Shi,[15] Hero of Alexandria,[16] Al-Jazari[17] and Wolfgang von Kempelen.[18] It was also widely believed that artificial beings had been created by Jābir ibn Hayyān,[19] Judah Loew[20] and Paracelsus.[21] By the 19th and 20th centuries, artificial beings had become a common feature in fiction, as in Mary Shelley's Frankenstein or Karel Čapek's R.U.R. (Rossum's Universal Robots).[22] Pamela McCorduck argues that all of these are examples of an ancient urge, as she describes it, "to forge the gods".[6] Stories of these creatures and their fates discuss many of the same hopes, fears and ethical concerns that are presented by artificial intelligence.

Mechanical or "formal" reasoning has been developed by philosophers and mathematicians since antiquity. The study of logic led directly to the invention of the programmable digital electronic computer, based on the work of mathematician Alan Turing and others. Turing's theory of computation suggested that a machine, by shuffling symbols as simple as "0" and "1", could simulate any conceivable act of mathematical deduction.[23] This, along with recent discoveries in neurology, information theory and cybernetics, inspired a small group of researchers to begin to seriously consider the possibility of building an electronic brain.[24]

The field of AI research was founded at a conference on the campus of Dartmouth College in the summer of 1956.[25] The attendees, including John McCarthy, Marvin Minsky, Allen Newell and Herbert Simon, became the leaders of AI research for many decades.[26] They and their students wrote programs that were, to most people, simply astonishing:[27] computers were solving word problems in algebra, proving logical theorems and speaking English.[28] By the middle of the 1960s, research in the U.S. was heavily funded by the Department of Defense[29] and laboratories had been established around the world.[30] AI's founders were profoundly optimistic about the future of the new field: Herbert Simon predicted that "machines will be capable, within twenty years, of doing any work a man can do"[31] and Marvin Minsky agreed, writing that "within a generation ... the problem of creating 'artificial intelligence' will substantially be solved".[32]

They had failed to recognize the difficulty of some of the problems they faced.[33] In 1974, in response to the criticism of England's Sir James Lighthill and ongoing pressure from Congress to fund more productive projects, the U.S. and British governments cut off all undirected, exploratory research in AI. The next few years, when funding for projects was hard to find, would later be called an "AI winter".[34]

In the early 1980s, AI research was revived by the commercial success of expert systems,[35] a form of AI program that simulated the knowledge and analytical skills of one or more human experts. By 1985 the market for AI had reached over a billion dollars. At the same time, Japan's fifth generation computer project inspired the U.S and British governments to restore funding for academic research in the field.[36] However, beginning with the collapse of the Lisp Machine market in 1987, AI once again fell into disrepute, and a second, longer lasting AI winter began.[37]

In the 1990s and early 21st century, AI achieved its greatest successes, albeit somewhat behind the scenes. Artificial intelligence is used for logistics, data mining, medical diagnosis and many other areas throughout the technology industry.[9] The success was due to several factors: the incredible power of computers today (see Moore's law), a greater emphasis on solving specific subproblems, the creation of new ties between AI and other fields working on similar problems, and above all a new commitment by researchers to solid mathematical methods and rigorous scientific standards.[38]

Challenges

Challenges facing researchers and scientists in simulating (or creating) intelligence has been broken down into a number of specific sub-challenges. These consist of particular traits or capabilities that researchers would like an intelligent system to display. The traits described below have received the most attention.[11]

Deduction, reasoning, problem solving

Early AI researchers developed algorithms that imitated the step-by-step reasoning that humans use when they solve puzzles, play board games or make logical deductions.[39] By the late 1980s and '90s, AI research had also developed highly successful methods for dealing with uncertain or incomplete information, employing concepts from probability and economics.[40]

For difficult problems, most of these algorithms can require enormous computational resources — most experience a "combinatorial explosion": the amount of memory or computer time required becomes astronomical when the problem goes beyond a certain size. The search for more efficient problem solving algorithms is a high priority for AI research.[41]

Human beings solve most of their problems using fast, intuitive judgments rather than the conscious, step-by-step deduction that early AI research was able to model.[42] AI has made some progress at imitating this kind of "sub-symbolic" problem solving: embodied agent approaches emphasize the importance of sensorimotor skills to higher reasoning; neural net research attempts to simulate the structures inside human and animal brains that gives rise to this skill.

Knowledge representation

Knowledge representation[43] and knowledge engineering[44] are central to AI research. Many of the problems machines are expected to solve will require extensive knowledge about the world. Among the things that AI needs to represent are: objects, properties, categories and relations between objects;[45] situations, events, states and time;[46] causes and effects;[47] knowledge about knowledge (what we know about what other people know);[48] and many other, less well researched domains. A complete representation of "what exists" is an ontology[49] (borrowing a word from traditional philosophy), of which the most general are called upper ontologies.

Among the most difficult problems in knowledge representation are:

Default reasoning and the qualification problem
Many of the things people know take the form of "working assumptions." For example, if a bird comes up in conversation, people typically picture an animal that is fist sized, sings, and flies. None of these things are true about all birds. John McCarthy identified this problem in 1969[50] as the qualification problem: for any commonsense rule that AI researchers care to represent, there tend to be a huge number of exceptions. Almost nothing is simply true or false in the way that abstract logic requires. AI research has explored a number of solutions to this problem.[51]
The breadth of commonsense knowledge
The number of atomic facts that the average person knows is astronomical. Research projects that attempt to build a complete knowledge base of commonsense knowledge (e.g., Cyc) require enormous amounts of laborious ontological engineering — they must be built, by hand, one complicated concept at a time.[52] A major goal is to have the computer understand enough concepts to be able to learn by reading from sources like the internet, and thus be able to add to its own ontology.
The subsymbolic form of some commonsense knowledge
Much of what people know is not represented as "facts" or "statements" that they could actually say out loud. For example, a chess master will avoid a particular chess position because it "feels too exposed"[53] or an art critic can take one look at a statue and instantly realize that it is a fake.[54] These are intuitions or tendencies that are represented in the brain non-consciously and sub-symbolically.[55] Knowledge like this informs, supports and provides a context for symbolic, conscious knowledge. As with the related problem of sub-symbolic reasoning, it is hoped that situated AI or computational intelligence will provide ways to represent this kind of knowledge.[55]

Planning

Intelligent agents must be able to set goals and achieve them.[56] They need a way to visualize the future (they must have a representation of the state of the world and be able to make predictions about how their actions will change it) and be able to make choices that maximize the utility (or "value") of the available choices.[57]

In classical planning problems, the agent can assume that it is the only thing acting on the world and it can be certain what the consequences of its actions may be.[58] However, if this is not true, it must periodically check if the world matches its predictions and it must change its plan as this becomes necessary, requiring the agent to reason under uncertainty.[59]

Multi-agent planning uses the cooperation and competition of many agents to achieve a given goal. Emergent behavior such as this is used by evolutionary algorithms and swarm intelligence.[60]

Learning

Machine learning[61] has been central to AI research from the beginning.[62] Unsupervised learning is the ability to find patterns in a stream of input. Supervised learning includes both classification and numerical regression. Classification is used to determine what category something belongs in, after seeing a number of examples of things from several categories. Regression takes a set of numerical input/output examples and attempts to discover a continuous function that would generate the outputs from the inputs. In reinforcement learning[63] the agent is rewarded for good responses and punished for bad ones. These can be analyzed in terms of decision theory, using concepts like utility. The mathematical analysis of machine learning algorithms and their performance is a branch of theoretical computer science known as computational learning theory.

Natural language processing

Natural language processing[64] gives machines the ability to read and understand the languages that humans speak. Many researchers hope that a sufficiently powerful natural language processing system would be able to acquire knowledge on its own, by reading the existing text available over the internet. Some straightforward applications of natural language processing include information retrieval (or text mining) and machine translation.[65]

Motion and manipulation

ASIMO uses sensors and intelligent algorithms to avoid obstacles and navigate stairs.

The field of robotics[66] is closely related to AI. Intelligence is required for robots to be able to handle such tasks as object manipulation[67] and navigation, with sub-problems of localization (knowing where you are), mapping (learning what is around you) and motion planning (figuring out how to get there).[68]

Perception

Machine perception[69] is the ability to use input from sensors (such as cameras, microphones, sonar and others more exotic) to deduce aspects of the world. Computer vision[70] is the ability to analyze visual input. A few selected subproblems are speech recognition,[71] facial recognition and object recognition.[72]

Social intelligence

Kismet, a robot with rudimentary social skills

Emotion and social skills[73] play two roles for an intelligent agent. First, it must be able to predict the actions of others, by understanding their motives and emotional states. (This involves elements of game theory, decision theory, as well as the ability to model human emotions and the perceptual skills to detect emotions.) Also, for good human-computer interaction, an intelligent machine also needs to display emotions. At the very least it must appear polite and sensitive to the humans it interacts with. At best, it should have normal emotions itself.

Creativity

TOPIO, a robot that can play table tennis, developed by TOSY.

A sub-field of AI addresses creativity both theoretically (from a philosophical and psychological perspective) and practically (via specific implementations of systems that generate outputs that can be considered creative).

General intelligence

Most researchers hope that their work will eventually be incorporated into a machine with general intelligence (known as strong AI), combining all the skills above and exceeding human abilities at most or all of them.[12] A few believe that anthropomorphic features like artificial consciousness or an artificial brain may be required for such a project.[74] A related area of computational research is Artificial Intuition and Artificial Imagination.

Many of the problems above are considered AI-complete: to solve one problem, you must solve them all. For example, even a straightforward, specific task like machine translation requires that the machine follow the author's argument (reason), know what is being talked about (knowledge), and faithfully reproduce the author's intention (social intelligence). Machine translation, therefore, is believed to be AI-complete: it may require strong AI to be done as well as humans can do it.[75]

Approaches

There is no established unifying theory or paradigm that guides AI research. Researchers disagree about many issues.[76] A few of the most long standing questions that have remained unanswered are these: should artificial intelligence simulate natural intelligence, by studying psychology or neurology? Or is human biology as irrelevant to AI research as bird biology is to aeronautical engineering?[77] Can intelligent behavior be described using simple, elegant principles (such as logic or optimization)? Or does it necessarily require solving a large number of completely unrelated problems?[78] Can intelligence be reproduced using high-level symbols, similar to words and ideas? Or does it require "sub-symbolic" processing?[79]

Cybernetics and brain simulation

There is no consensus on how closely the brain should be simulated.

In the 1940s and 1950s, a number of researchers explored the connection between neurology, information theory, and cybernetics. Some of them built machines that used electronic networks to exhibit rudimentary intelligence, such as W. Grey Walter's turtles and the Johns Hopkins Beast. Many of these researchers gathered for meetings of the Teleological Society at Princeton University and the Ratio Club in England.[24] By 1960, this approach was largely abandoned, although elements of it would be revived in the 1980s.

Symbolic

When access to digital computers became possible in the middle 1950s, AI research began to explore the possibility that human intelligence could be reduced to symbol manipulation. The research was centered in three institutions: CMU, Stanford and MIT, and each one developed its own style of research. John Haugeland named these approaches to AI "good old fashioned AI" or "GOFAI".[80]

Cognitive simulation
Economist Herbert Simon and Alan Newell studied human problem solving skills and attempted to formalize them, and their work laid the foundations of the field of artificial intelligence, as well as cognitive science, operations research and management science. Their research team used the results of psychological experiments to develop programs that simulated the techniques that people used to solve problems. This tradition, centered at Carnegie Mellon University would eventually culminate in the development of the Soar architecture in the middle 80s.[81][82]
Logic based
Unlike Newell and Simon, John McCarthy felt that machines did not need to simulate human thought, but should instead try to find the essence of abstract reasoning and problem solving, regardless of whether people used the same algorithms.[77] His laboratory at Stanford (SAIL) focused on using formal logic to solve a wide variety of problems, including knowledge representation, planning and learning.[83] Logic was also focus of the work at the University of Edinburgh and elsewhere in Europe which led to the development of the programming language Prolog and the science of logic programming.[84]
"Anti-logic" or "scruffy"
Researchers at MIT (such as Marvin Minsky and Seymour Papert)[85] found that solving difficult problems in vision and natural language processing required ad-hoc solutions – they argued that there was no simple and general principle (like logic) that would capture all the aspects of intelligent behavior. Roger Schank described their "anti-logic" approaches as "scruffy" (as opposed to the "neat" paradigms at CMU [disambiguation needed] and Stanford).[78] Commonsense knowledge bases (such as Doug Lenat's Cyc) are an example of "scruffy" AI, since they must be built by hand, one complicated concept at a time.[86]
Knowledge based
When computers with large memories became available around 1970, researchers from all three traditions began to build knowledge into AI applications.[87] This "knowledge revolution" led to the development and deployment of expert systems (introduced by Edward Feigenbaum), the first truly successful form of AI software.[35] The knowledge revolution was also driven by the realization that enormous amounts of knowledge would be required by many simple AI applications.

Sub-symbolic

During the 1960s, symbolic approaches had achieved great success at simulating high-level thinking in small demonstration programs. Approaches based on cybernetics or neural networks were abandoned or pushed into the background.[88] By the 1980s, however, progress in symbolic AI seemed to stall and many believed that symbolic systems would never be able to imitate all the processes of human cognition, especially perception, robotics, learning and pattern recognition. A number of researchers began to look into "sub-symbolic" approaches to specific AI problems.[79]

Bottom-up, embodied, situated, behavior-based or nouvelle AI
Researchers from the related field of robotics, such as Rodney Brooks, rejected symbolic AI and focused on the basic engineering problems that would allow robots to move and survive.[89] Their work revived the non-symbolic viewpoint of the early cybernetics researchers of the 50s and reintroduced the use of control theory in AI. These approaches are also conceptually related to the embodied mind thesis.
Computational Intelligence
Interest in neural networks and "connectionism" was revived by David Rumelhart and others in the middle 1980s.[90] These and other sub-symbolic approaches, such as fuzzy systems and evolutionary computation, are now studied collectively by the emerging discipline of computational intelligence.[91]

Statistical

In the 1990s, AI researchers developed sophisticated mathematical tools to solve specific subproblems. These tools are truly scientific, in the sense that their results are both measurable and verifiable, and they have been responsible for many of AI's recent successes. The shared mathematical language has also permitted a high level of collaboration with more established fields (like mathematics, economics or operations research). Stuart Russell and Peter Norvig describe this movement as nothing less than a "revolution" and "the victory of the neats."[38]

Integrating the approaches

Intelligent agent paradigm
An intelligent agent is a system that perceives its environment and takes actions which maximizes its chances of success. The simplest intelligent agents are programs that solve specific problems. The most complicated intelligent agents are rational, thinking humans.[92] The paradigm gives researchers license to study isolated problems and find solutions that are both verifiable and useful, without agreeing on one single approach. An agent that solves a specific problem can use any approach that works — some agents are symbolic and logical, some are sub-symbolic neural networks and others may use new approaches. The paradigm also gives researchers a common language to communicate with other fields—such as decision theory and economics—that also use concepts of abstract agents. The intelligent agent paradigm became widely accepted during the 1990s.[93]
Agent architectures and cognitive architectures
Researchers have designed systems to build intelligent systems out of interacting intelligent agents in a multi-agent system.[94] A system with both symbolic and sub-symbolic components is a hybrid intelligent system, and the study of such systems is artificial intelligence systems integration. A hierarchical control system provides a bridge between sub-symbolic AI at its lowest, reactive levels and traditional symbolic AI at its highest levels, where relaxed time constraints permit planning and world modelling.[95] Rodney Brooks' subsumption architecture was an early proposal for such a hierarchical system.

Tools

In the course of 50 years of research, AI has developed a large number of tools to solve the most difficult problems in computer science. A few of the most general of these methods are discussed below.

Search and optimization

Many problems in AI can be solved in theory by intelligently searching through many possible solutions:[96] Reasoning can be reduced to performing a search. For example, logical proof can be viewed as searching for a path that leads from premises to conclusions, where each step is the application of an inference rule.[97] Planning algorithms search through trees of goals and subgoals, attempting to find a path to a target goal, a process called means-ends analysis.[98] Robotics algorithms for moving limbs and grasping objects use local searches in configuration space.[67] Many learning algorithms use search algorithms based on optimization.

Simple exhaustive searches[99] are rarely sufficient for most real world problems: the search space (the number of places to search) quickly grows to astronomical numbers. The result is a search that is too slow or never completes. The solution, for many problems, is to use "heuristics" or "rules of thumb" that eliminate choices that are unlikely to lead to the goal (called "pruning the search tree"). Heuristics supply the program with a "best guess" for what path the solution lies on.[100]

A very different kind of search came to prominence in the 1990s, based on the mathematical theory of optimization. For many problems, it is possible to begin the search with some form of a guess and then refine the guess incrementally until no more refinements can be made. These algorithms can be visualized as blind hill climbing: we begin the search at a random point on the landscape, and then, by jumps or steps, we keep moving our guess uphill, until we reach the top. Other optimization algorithms are simulated annealing, beam search and random optimization.[101]

Evolutionary computation uses a form of optimization search. For example, they may begin with a population of organisms (the guesses) and then allow them to mutate and recombine, selecting only the fittest to survive each generation (refining the guesses). Forms of evolutionary computation include swarm intelligence algorithms (such as ant colony or particle swarm optimization)[102] and evolutionary algorithms (such as genetic algorithms[103] and genetic programming[104][105]).

Logic

Logic[106] was introduced into AI research by John McCarthy in his 1958 Advice Taker proposal.[107] Logic is used for knowledge representation and problem solving, but it can be applied to other problems as well. For example, the satplan algorithm uses logic for planning[108] and inductive logic programming is a method for learning.[109]

Several different forms of logic are used in AI research. Propositional or sentential logic[110] is the logic of statements which can be true or false. First-order logic[111] also allows the use of quantifiers and predicates, and can express facts about objects, their properties, and their relations with each other. Fuzzy logic,[112] is a version of first-order logic which allows the truth of a statement to be represented as a value between 0 and 1, rather than simply True (1) or False (0). Fuzzy systems can be used for uncertain reasoning and have been widely used in modern industrial and consumer product control systems. Default logics, non-monotonic logics and circumscription[51] are forms of logic designed to help with default reasoning and the qualification problem. Several extensions of logic have been designed to handle specific domains of knowledge, such as: description logics;[45] situation calculus, event calculus and fluent calculus (for representing events and time);[46] causal calculus;[47] belief calculus; and modal logics.[48]

Probabilistic methods for uncertain reasoning

Many problems in AI (in reasoning, planning, learning, perception and robotics) require the agent to operate with incomplete or uncertain information. Starting in the late 80s and early 90s, Judea Pearl and others championed the use of methods drawn from probability theory and economics to devise a number of powerful tools to solve these problems.[113][114]

Bayesian networks[115] are a very general tool that can be used for a large number of problems: reasoning (using the Bayesian inference algorithm),[116] learning (using the expectation-maximization algorithm),[117] planning (using decision networks)[118] and perception (using dynamic Bayesian networks).[119] Probabilistic algorithms can also be used for filtering, prediction, smoothing and finding explanations for streams of data, helping perception systems to analyze processes that occur over time[120] (e.g., hidden Markov models[121] or Kalman filters[122]).

A key concept from the science of economics is "utility": a measure of how valuable something is to an intelligent agent. Precise mathematical tools have been developed that analyze how an agent can make choices and plan, using decision theory, decision analysis,[123] information value theory.[57] These tools include models such as Markov decision processes,[124] dynamic decision networks,[124] game theory and mechanism design.[125]

Classifiers and statistical learning methods

The simplest AI applications can be divided into two types: classifiers ("if shiny then diamond") and controllers ("if shiny then pick up"). Controllers do however also classify conditions before inferring actions, and therefore classification forms a central part of many AI systems. Classifiers are functions that use pattern matching to determine a closest match. They can be tuned according to examples, making them very attractive for use in AI. These examples are known as observations or patterns. In supervised learning, each pattern belongs to a certain predefined class. A class can be seen as a decision that has to be made. All the observations combined with their class labels are known as a data set. When a new observation is received, that observation is classified based on previous experience.[126]

A classifier can be trained in various ways; there are many statistical and machine learning approaches. The most widely used classifiers are the neural network,[127] kernel methods such as the support vector machine,[128] k-nearest neighbor algorithm,[129] Gaussian mixture model,[130] naive Bayes classifier,[131] and decision tree.[132] The performance of these classifiers have been compared over a wide range of tasks. Classifier performance depends greatly on the characteristics of the data to be classified. There is no single classifier that works best on all given problems; this is also referred to as the "no free lunch" theorem. Determining a suitable classifier for a given problem is still more an art than science.[133]

Neural networks

A neural network is an interconnected group of nodes, akin to the vast network of neurons in the human brain.

The study of artificial neural networks[127] began in the decade before the field AI research was founded, in the work of Walter Pitts and Warren McCullough. Other important early researchers were Frank Rosenblatt, who invented the perceptron and Paul Werbos who developed the backpropagation algorithm.[134]

The main categories of networks are acyclic or feedforward neural networks (where the signal passes in only one direction) and recurrent neural networks (which allow feedback). Among the most popular feedforward networks are perceptrons, multi-layer perceptrons and radial basis networks.[135] Among recurrent networks, the most famous is the Hopfield net, a form of attractor network, which was first described by John Hopfield in 1982.[136] Neural networks can be applied to the problem of intelligent control (for robotics) or learning, using such techniques as Hebbian learning and competitive learning.[137]

Jeff Hawkins argues that research in neural networks has stalled because it has failed to model the essential properties of the neocortex, and has suggested a model (Hierarchical Temporal Memory) that is based on neurological research.[138]

Control theory

Control theory, the grandchild of cybernetics, has many important applications, especially in robotics.[139]

Languages

AI researchers have developed several specialized languages for AI research, including Lisp[140] and Prolog.[141]

Evaluating progress

How can one determine if an agent is intelligent? In 1950, Alan Turing proposed a general procedure to test the intelligence of an agent now known as the Turing test. This procedure allows almost all the major problems of artificial intelligence to be tested. However, it is a very difficult challenge and at present all agents fail.

Artificial intelligence can also be evaluated on specific problems such as small problems in chemistry, hand-writing recognition and game-playing. Such tests have been termed subject matter expert Turing tests. Smaller problems provide more achievable goals and there are an ever-increasing number of positive results.

The broad classes of outcome for an AI test are:

  • Optimal: it is not possible to perform better
  • Strong super-human: performs better than all humans
  • Super-human: performs better than most humans
  • Sub-human: performs worse than most humans

For example, performance at draughts is optimal,[142] performance at chess is super-human and nearing strong super-human,[143] and performance at many everyday tasks performed by humans is sub-human.

A quite different approach measures machine intelligence through tests which are developed from mathematical definitions of intelligence. Examples of these kinds of tests start in the late nineties devising intelligence tests using notions from Kolmogorov Complexity and data compression [144] [145]. Similar definitions of machine intelligence have been put forward by Marcus Hutter in his book Universal Artificial Intelligence (Springer 2005), an idea further developed by Legg and Hutter [146]. Two major advantages of mathematical definitions are their applicability to nonhuman intelligences and their absence of a requirement for human testers.

Applications

Artificial intelligence has successfully been used in a wide range of fields including medical diagnosis, stock trading, robot control, law, scientific discovery, video games, toys, and Web search engines. Frequently, when a technique reaches mainstream use, it is no longer considered artificial intelligence, sometimes described as the AI effect.[147] It may also become integrated into artificial life.

Competitions and prizes

There are a number of competitions and prizes to promote research in artificial intelligence. The main areas promoted are: general machine intelligence, conversational behavior, data-mining, driverless cars, robot soccer and games.

Platforms

A platform (or "computing platform")is defined by Wikipedia as "some sort of hardware architecture or software framework (including application frameworks), that allows software to run." As Rodney Brooks [148]pointed out many years ago, it is not just the artificial intelligence software that defines the AI features of the platform, but rather the actual platform itself that affects the AI that results, ie, we need to be working out AI problems on real world platforms rather than in isolation.

A wide variety of platforms has allowed different aspects of AI to develop, ranging from expert systems, albeit PC-based but still an entire real-world system to various robot platforms such as the widely available Roomba with open interface [149].


Philosophy

Artificial intelligence, by claiming to be able to recreate the capabilities of the human mind, is both a challenge and an inspiration for philosophy. Are there limits to how intelligent machines can be? Is there an essential difference between human intelligence and artificial intelligence? Can a machine have a mind and consciousness? A few of the most influential answers to these questions are given below.[150]

Turing's "polite convention"
If a machine acts as intelligently as a human being, then it is as intelligent as a human being. Alan Turing theorized that, ultimately, we can only judge the intelligence of a machine based on its behavior. This theory forms the basis of the Turing test.[151]
The Dartmouth proposal
"Every aspect of learning or any other feature of intelligence can be so precisely described that a machine can be made to simulate it." This assertion was printed in the proposal for the Dartmouth Conference of 1956, and represents the position of most working AI researchers.[152]
Newell and Simon's physical symbol system hypothesis
"A physical symbol system has the necessary and sufficient means of general intelligent action." Newell and Simon argue that intelligences consists of formal operations on symbols.[153] Hubert Dreyfus argued that, on the contrary, human expertise depends on unconscious instinct rather than conscious symbol manipulation and on having a "feel" for the situation rather than explicit symbolic knowledge. (See Dreyfus' critique of AI.)[154][155]
Gödel's incompleteness theorem
A formal system (such as a computer program) can not prove all true statements. Roger Penrose is among those who claim that Gödel's theorem limits what machines can do. (See The Emperor's New Mind.)[156][157]
Searle's strong AI hypothesis
"The appropriately programmed computer with the right inputs and outputs would thereby have a mind in exactly the same sense human beings have minds."[158] Searle counters this assertion with his Chinese room argument, which asks us to look inside the computer and try to find where the "mind" might be.[159]
The artificial brain argument
The brain can be simulated. Hans Moravec, Ray Kurzweil and others have argued that it is technologically feasible to copy the brain directly into hardware and software, and that such a simulation will be essentially identical to the original.[160]

Prediction

AI is a common topic in both science fiction and in projections about the future of technology and society. The existence of an artificial intelligence that rivals human intelligence raises difficult ethical issues and the potential power of the technology inspires both hopes and fears.

Mary Shelley's Frankenstein[161] considers a key issue in the ethics of artificial intelligence: if a machine can be created that has intelligence, could it also feel? If it can feel, does it have the same rights as a human? The idea also appears in modern science fiction: the film Artificial Intelligence: A.I. considers a machine in the form of a small boy which has been given the ability to feel human emotions, including, tragically, the capacity to suffer. This issue, now known as "robot rights", is currently being considered by, for example, California's Institute for the Future,[162] although many critics believe that the discussion is premature.[163]

Another issue explored by both science fiction writers and futurists is the impact of artificial intelligence on society. In fiction, AI has appeared fulfilling many roles including;

Academic sources have considered such consequences as: a decreased demand for human labor,[164] the enhancement of human ability or experience,[165] and a need for redefinition of human identity and basic values.[166]

Andrew Kennedy in his musing on the evolution of the human personality [167] considered that artificial intelligences or 'new minds' are likely to have severe personality disorders, and identifies four particular types that are likely to arise: the autistic, the collector, the ecstatic, the victim and suggests that they will need humans because of our superior understanding of personality and the role of the unconscious.

Several futurists argue that artificial intelligence will transcend the limits of progress and fundamentally transform humanity. Ray Kurzweil has used Moore's law (which describes the relentless exponential improvement in digital technology with uncanny accuracy) to calculate that desktop computers will have the same processing power as human brains by the year 2029, and that by 2045 artificial intelligence will reach a point where it is able to improve itself at a rate that far exceeds anything conceivable in the past, a scenario that science fiction writer Vernor Vinge named the "technological singularity".[165] Edward Fredkin argues that "artificial intelligence is the next stage in evolution,"[168] an idea first proposed by Samuel Butler's "Darwin among the Machines" (1863), and expanded upon by George Dyson in his book of the same name in 1998. Several futurists and science fiction writers have predicted that humans and machines will merge in the future into cyborgs that are more capable and powerful than either. This idea, called transhumanism, which has roots in Aldous Huxley and Robert Ettinger, is now associated with robot designer Hans Moravec, cyberneticist Kevin Warwick and inventor Ray Kurzweil.[165] Transhumanism has been illustrated in fiction as well, for example in the manga Ghost in the Shell and the science fiction series Dune. Pamela McCorduck writes that these scenarios are expressions of the ancient human desire to, as she calls it, "forge the gods."[6]

See also

Notes

  1. ^ Poole, Mackworth & Goebel 1998, p. 1 (who use the term "computational intelligence" as a synonym for artificial intelligence). Other textbooks that define AI this way include Nilsson (1998), and Russell & Norvig (2003) (who prefer the term "rational agent") and write "The whole-agent view is now widely accepted in the field" (Russell & Norvig 2003, p. 55)
  2. ^ This definition, in terms of goals, actions, perception and environment, is due to Russell & Norvig (2003). Other definitions also include knowledge and learning as additional criteria.
  3. ^ Although there is some controversy on this point (see Crevier 1993, p. 50), McCarthy states unequivocally "I came up with the term" in a c|net interview. (See Getting Machines to Think Like Us.)
  4. ^ See John McCarthy, What is Artificial Intelligence?
  5. ^ See the Dartmouth proposal, under Philosophy, below.
  6. ^ a b c This is a central idea of Pamela McCorduck's Machines That Think. She writes: "I like to think of artificial intelligence as the scientific apotheosis of a venerable cultural tradition." (McCorduck 2004, p. 34) "Artificial intelligence in one form or another is an idea that has pervaded Western intellectual history, a dream in urgent need of being realized." (McCorduck 2004, p. xviii) "Our history is full of attempts—nutty, eerie, comical, earnest, legendary and real—to make artificial intelligences, to reproduce what is the essential us—bypassing the ordinary means. Back and forth between myth and reality, our imaginations supplying what our workshops couldn't, we have engaged for a long time in this odd form of self-reproduction." (McCorduck 2004, p. 3) She traces the desire back to its Hellenistic roots and calls it the urge to "forge the Gods." (McCorduck 2004, p. 340-400)
  7. ^ The optimism referred to includes the predictions of early AI researchers (see optimism in the history of AI) as well as the ideas of modern transhumanists such as Ray Kurzweil.
  8. ^ The "setbacks" referred to include the ALPAC report of 1966, the abandonment of perceptrons in 1970, the the Lighthill Report of 1973 and the collapse of the lisp machine market in 1987.
  9. ^ a b AI applications widely used behind the scenes:
  10. ^ Pamela McCorduck (2004, pp. 424) writes of "the rough shattering of AI in subfields—vision, natural language, decision theory, genetic algorithms, robotics ... and these with own sub-subfield—that would hardly have anything to say to each other."
  11. ^ a b This list of intelligent traits is based on the topics covered by the major AI textbooks, including:
  12. ^ a b General intelligence (strong AI) is discussed in popular introductions to AI:
  13. ^ AI in Myth:
  14. ^ Sacred statues as artificial intelligence: These were the first machines to be believed to have true intelligence and consciousness. Hermes Trismegistus expressed the common belief that with these statues, craftsman had reproduced "the true nature of the gods", their sensus and spiritus. McCorduck makes the connection between sacred automatons and Mosaic law (developed around the same time), which expressly forbids the worship of robots (McCorduck 2004, pp. 6-9)
  15. ^ Needham 1986, p. 53
  16. ^ McCorduck 2004, p. 6
  17. ^ "A Thirteenth Century Programmable Robot". Shef.ac.uk. http://www.shef.ac.uk/marcoms/eview/articles58/robot.html. Retrieved 2009-04-25. 
  18. ^ McCorduck 2004, p. 17
  19. ^ Takwin: O'Connor, Kathleen Malone (1994). The alchemical creation of life (takwin) and other concepts of Genesis in medieval Islam. University of Pennsylvania. http://repository.upenn.edu/dissertations/AAI9503804. Retrieved 2007-01-10. 
  20. ^ Golem: McCorduck 2004, p. 15-16, Buchanan 2005, p. 50
  21. ^ McCorduck 2004, p. 13-14
  22. ^ McCorduck 2004, pp. 17-25
  23. ^ This insight, that digital computers can simulate any process of formal reasoning, is known as the Church-Turing thesis.
  24. ^ a b AI's immediate precursors: See also Cybernetics and early neural networks (in History of artificial intelligence). Among the researchers who laid the foundations of AI were Alan Turing, John Von Neumann, Norbert Weiner, Claude Shannon, Warren McCullough, Walter Pitts and Donald Hebb.
  25. ^ Dartmouth conference:
  26. ^ Hegemony of the Dartmouth conference attendees:
  27. ^ Russell and Norvig write "it was astonishing whenever a computer did anything kind of smartish." Russell & Norvig 2003, p. 18
  28. ^ "Golden years" of AI (successful symbolic reasoning programs 1956-1973): The programs described are Daniel Bobrow's STUDENT, Newell and Simon's Logic Theorist and Terry Winograd's SHRDLU.
  29. ^ DARPA pours money into undirected pure research into AI during the 1960s:
  30. ^
  31. ^ Simon 1965, p. 96 quoted in Crevier 1993, p. 109
  32. ^ Minsky 1967, p. 2 quoted in Crevier 1993, p. 109.
  33. ^ See The problems (in History of artificial intelligence).
  34. ^ First AI Winter, Mansfield Amendment, Lighthill report
  35. ^ a b Expert systems:
  36. ^ Boom of the 1980s: rise of expert systems, Fifth Generation Project, Alvey, MCC, SCI:
  37. ^ Second AI Winter:
  38. ^ a b Formal methods are now preferred ("Victory of the neats"):
  39. ^ Problem solving, puzzle solving, game playing and deduction:
  40. ^ Uncertain reasoning:
  41. ^ Intractability and efficiency and the combinatorial explosion:
  42. ^ Cognitive science has provided several famous examples:
  43. ^ Knowledge representation:
  44. ^ Knowledge engineering:
  45. ^ a b Representing categories and relations: Semantic networks, description logics, inheritance (including frames and scripts):
  46. ^ a b Representing events and time:Situation calculus, event calculus, fluent calculus (including solving the frame problem):
  47. ^ a b Causal calculus:
  48. ^ a b Representing knowledge about knowledge: Belief calculus, modal logics:
  49. ^ Ontology:
  50. ^ McCarthy & Hayes 1969. While McCarthy was primarily concerned with issues in the logical representation of actions, Russell & Norvig 2003 apply the term to the more general issue of default reasoning in the vast network of assumptions underlying all our commonsense knowledge.
  51. ^ a b Default reasoning and default logic, non-monotonic logics, circumscription, closed world assumption, abduction (Poole et al. places abduction under "default reasoning". Luger et al. places this under "uncertain reasoning"):
  52. ^ Breadth of commonsense knowledge:
  53. ^ Dreyfus & Dreyfus 1986
  54. ^ Gladwell 2005
  55. ^ a b Expert knowledge as embodied [disambiguation needed] intuition:
  56. ^ Planning:
  57. ^ a b Information value theory:
  58. ^ Classical planning:
  59. ^ Planning and acting in non-deterministic domains: conditional planning, execution monitoring, replanning and continuous planning:
  60. ^ Multi-agent planning and emergent behavior:
  61. ^ Learning:
  62. ^ Alan Turing discussed the centrality of learning as early as 1950, in his classic paper Computing Machinery and Intelligence. (Turing 1950)
  63. ^ Reinforcement learning:
  64. ^ Natural language processing:
  65. ^ Applications of natural language processing, including information retrieval (i.e. text mining) and machine translation:
  66. ^ Robotics:
  67. ^ a b Moving and configuration space:
  68. ^ Robotic mapping (localization, etc):
  69. ^ Machine perception:
  70. ^ Computer vision:
  71. ^ Speech recognition:
  72. ^ Object recognition:
  73. ^ Emotion and affective computing:
  74. ^ Gerald Edelman, Igor Aleksander and others have both argued that artificial consciousness is required for strong AI. (Aleksander 1995) (Edelman 2007) Ray Kurzweil, Jeff Hawkins and others have argued that strong AI requires a simulation of the operation of the human brain. (Hawkins & Blakeslee 2004) (Kurzweil 2005)
  75. ^ AI complete: Shapiro 1992, p. 9
  76. ^ Nils Nilsson writes: "Simply put, there is wide disagreement in the field about what AI is all about." (Nilsson 1983, p. 10)
  77. ^ a b Biological intelligence vs. intelligence in general:
    • Russell & Norvig 2003, pp. 2-3, who make the analogy with aeronautical engineering.
    • McCorduck 2004, pp. 100-101, who writes that there are "two major branches of artifical intelligence: one aimed at producing intelligent behavior regardless of how it was accomplioshed, and the other aimed at modeling intelligent processes found in nature, particularly human ones."
    • Kolata 1982, a paper in Science, which describes McCathy's indifference to biological models. Kolata quotes McCarthy as writing: "This is AI, so we don't care if it's psychologically real"[1]. McCarthy recently reiterated his position at the AI@50 conference where he said "Artificial intelligence is not, by definition, simulation of human intelligence" (Maker 2006).
  78. ^ a b Neats vs. scruffies:
  79. ^ a b Symbolic vs. sub-symbolic AI:
  80. ^ Haugeland 1985, pp. 112-117
  81. ^ Cognitive simulation, Newell and Simon, AI at CMU [disambiguation needed] (then called Carnegie Tech):
  82. ^ Soar (history):
  83. ^ McCarthy and AI research at SAIL and SRI:
  84. ^ AI research at Edinburgh and in France, birth of Prolog:
  85. ^ AI at MIT under Marvin Minsky in the 1960s :
  86. ^ Cyc:
  87. ^ Knowledge revolution:
  88. ^ The most dramatic case of sub-symbolic AI being pushed into the background was the devastating critique of perceptrons by Marvin Minsky and Seymour Papert in 1969. See History of AI, AI winter, or Frank Rosenblatt.
  89. ^ Embodied approaches to AI:
  90. ^ Revival of connectionism:
  91. ^ See IEEE Computational Intelligence Society
  92. ^ The intelligent agent paradigm:
  93. ^ "The whole-agent view is now widely accepted in the field" Russell & Norvig 2003, p. 55
  94. ^ Agent architectures, hybrid intelligent systems:
  95. ^ Albus, J. S. 4-D/RCS reference model architecture for unmanned ground vehicles. In G Gerhart, R Gunderson, and C Shoemaker, editors, Proceedings of the SPIE AeroSense Session on Unmanned Ground Vehicle Technology, volume 3693, pages 11—20
  96. ^ Search algorithms:
  97. ^ Forward chaining, backward chaining, Horn clauses, and logical deduction as search:
  98. ^ State space search and planning:
  99. ^ Uninformed searches (breadth first search, depth first search and general state space search):
  100. ^ Heuristic or informed searches (e.g., greedy best first and A*):
  101. ^ Optimization searches:
  102. ^ Artificial life and society based learning:
  103. ^ Genetic algorithms for learning: See also: Holland, John H. (1975). Adaptation in Natural and Artificial Systems. University of Michigan Press. ISBN 0262581116. 
  104. ^ Koza, John R. (1992). Genetic Programming. MIT Press. ISBN 0262111705. 
  105. ^ Poli, R., Langdon, W. B., McPhee, N. F. (2008). A Field Guide to Genetic Programming. Lulu.com, freely available from http://www.gp-field-guide.org.uk/. ISBN 978-1-4092-0073-4. 
  106. ^ Logic:
  107. ^ History of logic programming: Advice Taker:
  108. ^ Satplan:
  109. ^ Explanation based learning, relevance based learning, inductive logic programming, case based reasoning:
  110. ^ Propositional logic:
  111. ^ First-order logic and features such as equality:
  112. ^ Fuzzy logic:
  113. ^ Judea Pearl's contribution to AI:
  114. ^ Stochastic methods for uncertain reasoning:
  115. ^ Bayesian networks:
  116. ^ Bayesian inference algorithm:
  117. ^ Bayesian learning and the expectation-maximization algorithm:
  118. ^ Bayesian decision networks:
  119. ^ Dynamic Bayesian network:
  120. ^ Stochastic temporal models: Russell & Norvig 2003, pp. 537-581
  121. ^ Hidden Markov model:
  122. ^ Kalman filter:
  123. ^ decision theory and decision analysis:
  124. ^ a b Markov decision processes and dynamic decision networks:
  125. ^ Game theory and mechanism design:
  126. ^ Statistical learning methods and classifiers:
  127. ^ a b Neural networks and connectionism:
  128. ^ Kernel methods:
  129. ^ K-nearest neighbor algorithm:
  130. ^ Gaussian mixture model:
  131. ^ Naive Bayes classifier:
  132. ^ Decision tree:
  133. ^ van der Walt 2006
  134. ^ Backpropagation:
  135. ^ Feedforward networks, perceptrons radial basis networks:
  136. ^ Recurrent networks, Hopfield nets:
  137. ^ Competitive learning, Hebbian coincidence learning, Hopfield networks and attractor networks:
  138. ^ Hawkins & Blakeslee 2004
  139. ^ Control theory:
  140. ^ Lisp:
  141. ^ Prolog:
  142. ^ Schaeffer, Jonathan (2007-07-19). "Checkers Is Solved". Science. http://www.sciencemag.org/cgi/content/abstract/1144079. Retrieved 2007-07-20. 
  143. ^ Computer Chess#Computers versus humans
  144. ^ Jose Hernandez-Orallo (2000). "Beyond the Turing Test". Journal of Logic, Language and Information 9 (4): 447–466. doi:10.1023/A:1008367325700. http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.44.8943. Retrieved 2009-07-21. 
  145. ^ D L Dowe and A R Hajek (1997). "A computational extension to the Turing Test". Proceedings of the 4th Conference of the Australasian Cognitive Science Society. http://www.csse.monash.edu.au/publications/1997/tr-cs97-322-abs.html. Retrieved 2009-07-21. 
  146. ^ Shane Legg and Marcus Hutter (2007). "Universal Intelligence: A Definition of Machine Intelligence" (pdf). Minds and Machines 17: 391–444. doi:10.1007/s11023-007-9079-x. http://www.vetta.org/documents/UniversalIntelligence.pdf. Retrieved 2009-07-21. 
  147. ^ "AI set to exceed human brain power" (web article). CNN.com. 2006-07-26. http://www.cnn.com/2006/TECH/science/07/24/ai.bostrom/. Retrieved 2008-02-26. 
  148. ^ Brooks, R.A., "How to build complete creatures rather than isolated cognitive simulators," in K. VanLehn (ed.), Architectures for Intelligence, pp. 225-239, Lawrence Erlbaum Assosiates, Hillsdale, NJ, 1991.
  149. ^ http://hackingroomba.com/?s=atmel
  150. ^ All of these positions below are mentioned in standard discussions of the subject, such as:
  151. ^ Philosophical implications of the Turing test:
  152. ^ Dartmouth proposal:
  153. ^ The physical symbol systems hypothesis:
  154. ^ Dreyfus criticized the necessary condition of the physical symbol system hypothesis, which he called the "psychological assumption": "The mind can be viewed as a device operating on bits of information according to formal rules". (Dreyfus 1992, p. 156)
  155. ^ Dreyfus' critique of artificial intelligence:
  156. ^ This is a paraphrase of the important implication of Gödel's theorems.
  157. ^ The Mathematical Objection: Making the Mathematical Objection: Refuting Mathematical Objection: Background:
  158. ^ This version is from Searle (1999), and is also quoted in Dennett 1991, p. 435. Searle's original formulation was "The appropriately programmed computer really is a mind, in the sense that computers given the right programs can be literally said to understand and have other cognitive states." (Searle 1980, p. 1). Strong AI is defined similarly by Russell & Norvig (2003, p. 947): "The assertion that machines could possibly act intelligently (or, perhaps better, act as if they were intelligent) is called the 'weak AI' hypothesis by philosophers, and the assertion that machines that do so are actually thinking (as opposed to simulating thinking) is called the 'strong AI' hypothesis."
  159. ^ Searle's Chinese Room argument:
  160. ^ Artificial brain: The most extreme form of this argument (the brain replacement scenario) was put forward by Clark Glymour in the mid-70s and was touched on by Zenon Pylyshyn and John Searle in 1980. Daniel Dennett sees human consciousness as multiple functional thought patterns; see "Consciousness Explained".
  161. ^ McCorduck (2004, p. 190-25) discusses Frankenstein and identifies the key ethical issues as scientific hubris and the suffering of the monster, i.e. robot rights.
  162. ^ Robot rights:
  163. ^ See the Times Online, Human rights for robots? We’re getting carried away
  164. ^ Russell & Norvig (2003, p. 960-961)
  165. ^ a b c Singularity, transhumanism:
  166. ^ Joseph Weizenbaum's critique of AI: Weizenbaum (the AI researcher who developed the first chatterbot program, ELIZA) argued in 1976 that the misuse of artificial intelligence has the potential to devalue human life.
  167. ^ Kennedy, Andrew (2009), 'Who is human anyway?', pp=221- 234, "Essential Personalities, and why humans found love, adapted to monogamy and became better parents", Gravity Publishing, UK, ISBN 9780954483142
  168. ^ Quoted in McCorduck (2004, p. 401)

References

Major AI textbooks
See also A.I. Textbook survey
History of AI
Other sources

Further reading

  • R. Sun & L. Bookman, (eds.), Computational Architectures: Integrating Neural and Symbolic Processes. Kluwer Academic Publishers, Needham, MA. 1994.
  • Margaret Boden, Mind As Machine, Oxford University Press, 2006
  • John Johnston, (2008) "The Allure of Machinic Life: Cybernetics, Artificial Life, and the New AI", MIT Press
  • Courtney Boyd Myers ed. (2009). The AI Report. Forbes June 2009

External links

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Translations: Ai
Top

Dansk (Danish)
1.
n. - tretået dovendyr

2.
abbr. - kunstig intelligens, AI

Nederlands (Dutch)
K.I., A.I.

Français (French)
1.
n. - (Zool) aï, (Zool) paresseux

2.
abbr. - (abrév = airborne intercept) (Aviat) avion d'interception, interception aéroportée

abbr. - Intelligence artificielle, Insémination artificielle, Amnesty International

Deutsch (German)
n. - Ai, dreizehiges Faultier

abbr. - künstliche Intelligenz/Besamung

Ελληνική (Greek)
abbr. - τεχνητή νοημοσύνη

Italiano (Italian)
inseminazione artificiale, intelligenza artificiale

Português (Portuguese)
abbr. - interceptação (f) aérea (Mil.), inseminação (f) artificial (Med.) (Zool.), inteligência (f) artificial (Inf.)

Русский (Russian)
искусственный разум

Español (Spanish)
1.
n. - mamífero desdentado del norte de Brasil y Venezuela

2.
abbr. - inteligencia artificial

abbr. - inseminación artificial, Amnistía Internacional

Svenska (Swedish)
abbr. - konstgjord intelligens, konstgjord befruktning

中文(简体)(Chinese (Simplified))
1. 三趾树獭

2. 偶然招致的, 遭遇意外, 人工智能, 人工授精, 机载截听

中文(繁體)(Chinese (Traditional))
1.
abbr. - 偶然招致的, 遭遇意外, 人工智慧, 人工授精, 機載截聽

2.
n. - 三趾樹獺

한국어 (Korean)
1.
n. - 세손가락 나무늘보

2.
abbr. - artificial intelligence(인공지능)

日本語 (Japanese)
n. - 人工知能

العربيه (Arabic)
‏(اختصار) أختصار معناه : ألذكاء ألإصطناعي, ألإخصاب ألإصطناعي‏

עברית (Hebrew)
n. - ‮עצלן תלת-האצבע (חיה המצויה בדרום אמריקה)‬
abbr. - ‮הזרעה מלאכותית, בינה מלאכותית‬


 
 

 

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