The NOT-SO-DETAILS Definition:
So the basic question should be What is Artificial Intelligence? For this we have to know what is intelligence. In a word Intelligence is the computational part of the ability to achieve goals in the world. Varying kinds and degrees of intelligence occur in people and many animals. There is no solid definition of intelligence that doesn't depend on relating to human intelligence. The problem is that we cannot yet characterize in general what kinds of computational procedures we want to call intelligent. We understand some of the mechanisms of intelligence and not others. And AI is the science and engineering of making intelligent machines, especially intelligent computer programs. It is related to the similar task of using computers to understand human intelligence, but AI does not have to confine itself to methods that are biologically observable. Actually it is a combination of computer science, physiology and philosophy. AI is a broad topic, consisting of different fields, from machine vision to expert systems. The element that the fields of AI have in common is the creation of machines that can "think".
AI is somewhat different to IQ. IQ is based on the rates at which intelligence develops in children. It is the ratio of the age at which a child normally makes a certain score to the child's age. The scale is extended to adults in a suitable way. IQ correlates well with various measures of success or failure in life, but making computers that can score high on IQ tests would be weakly correlated with their usefulness.
The Short History:
The beginnings of AI reach back before electronics,to philosophers and mathematicians such as George Boole and others theorizing on principles that were used as the foundation of AI Logic. AI really began to intrigue researchers with the invention of the computer in 1943. The technology was finally a
vailable, or so it seemed, to simulate intelligent behavior.
In 1961, A.L. Samuel Developed a program which learned to play checkers at Masters level. J.A. Robinson introduced resolution as an inference method in logic in 1965. In the same year work on DENDRAL was begun at Stanford University. DENDRAL is an expert system which discovers molecule structure given only information of the constituents of the compound and mass spectra data. DENDRAL was the first knowledge-based expert system to be developed. After three years, in 1968 work on MACSYMA was initiated at MIT. MACSYMA is a large interactive program which solves numerous types of mathematical problems. Written in LISP, MACSYMA was a continuation of earlier work on SIN, an indefinite integration solving problem.
Over the next four decades, despite many stumbling blocks, AI has grown from a dozen researchers, to thousands of engineers and specialists; and from programs capable of playing checkers, to systems designed to diagnose disease.
The Turing Test:
Perhaps the best way to gauge the intelligence of a machine is British computer scientist Alan Turing's test. He stated that a computer would deserves to be called intelligent if it could deceive a human into believing that it was human. It was developed in 1950, allows subjects to interact with a person or a computer in another room by speaking into a microphone or typing questions on to a computer. When they receive an answer by voice synthesizer or by text on their computers screens, subjects must determine whether they have been communicating with a computer or a human. If they think that they have been interacting with a person or they are unable to decide, then the computer has passed the Turing Test, proving that the machine is actually capable of higher level thought processes similar to those of a human brain.
But is Turing Test flawless? A machined can be programmed to produce responses that appear to be intelligent without the awareness required for thought. According to the philosopher John Searle in his famous Chinese Room Argument, an English-speaking person is able to to respond to questions in Chinese by referring to source material that allows him to break the code without comprehending the underlying meaning of the symbols. The person can behave correctly without the higher level thought requires to process the meaning. Therefore, a computer could pass the Turing test if it were programmed to generate behavioral output but the Turing Test itself would be flawed. This test is not enough to prove that machine can think. Whatever the fact is, no superior test to Turing Test is invented yet.
Methods Used to Create Intelligence:
In the quest to create intelligent machines, the field of Artificial Intelligence has split into several different approaches. These rivaling theories have lead researchers in one of two basic approaches: bottom-up and top-down. Bottom-up theorists believe the best way to achieve artificial intelligence is to build electronic replicas of the human brain's complex network of neurons, while the top-down approach attempts to mimic the brain's behavior with computer programs.
(i) Neural Networks and Parallel Computation:
The human brain is made up of a web of billions of cells called neurons, and understanding its complexities is seen as one of the last frontiers in scientific research. It is the aim of AI researchers who prefer this bottom-up approach to construct electronic circuits that act as neurons do in the human brain. Although much of the working of the brain remains unknown, the complex network of neurons is what gives humans intelligent characteristics. By itself, a neuron is not intelligent, but when grouped together, neurons are able to pass electrical signals through networks.
A century earlier the true / false nature of binary numbers was theorized in 1854 by George Boole in his postulates concerning the Laws of Thought. Boole's principles make up what is known as Boolean algebra, the collection of logic concerning AND, OR, NOT operands. For example according to the Laws of thought the statement: (for this example consider all apples are red)
- Apples are red-- is True
- Apples are red AND oranges are purple-- is False
- Apples are red OR oranges are purple-- is True
- Apples are red AND oranges are NOT purple-- is also True
Boole also assumed that the human mind works according to these laws, it performs logical operations that could be reasoned. Ninety years later, Claude Shannon applied Boole's principles in circuits, the blueprint for electronic computers. Boole's contribution to the future of computing and Artificial Intelligence was immeasurable, and his logic is the basis of neural networks.
(ii) Top Down Approaches (Expert System):
Because of the large storage capacity of computers, expert systems had the potential to interpret statistics, in order to formulate rules. An expert system works much like a detective solves a mystery. Using the information, and logic or rules, an expert system can solve the problem. For example if the expert system was designed to distinguish birds it may have the logic trees like the figure. Charts like these represent the logic of expert systems. Using a similar set of rules, experts can have a variety of applications. With improved interfacing, computers may begin to find a larger place in society.
(iii) Chess:
AI-based game playing programs combine intelligence with entertainment. On game with strong AI ties is chess. World-champion chess playing programs can see ahead twenty plus moves in advance for each move they make. In addition, the programs have an ability to get progressively better over time because of the ability to learn. Chess programs do not play chess as humans do. In three minutes, Deep Thought (a master program) considers 126 million moves, while human chess-master on average considers less than 2 moves.
(iv) Frames:
On method that many programs use to represent knowledge are frames. Pioneered by Marvin Minsky, frame theory revolves around packets of information. For example, say the situation was a birthday party. A computer could call on its birthday frame, and use the information contained in the frame, to apply to the situation. The computer knows that there is usually cake and presents because of the information contained in the knowledge frame. Frames can also overlap, or contain sub-frames. The use of frames also allows the computer to add knowledge. Although not embraced by all AI developers, frames have been used in comprehension programs.
Specialized Languages for A.I.:
AI research has led to many advances in programming languages including the first list processing language by Allen Newell et al., Lisp dialects, Planner, Actors, the Scientific Community Metaphor, production systems, and rule-based languages.
GOFAI research is often done in programming languages such as Prolog or Lisp. Matlab and Lush include many specialist probabilistic libraries for Bayesian systems. AI research often emphasizes rapid development and prototyping, using such interpreted languages to empower rapid command-line testing and experimentation. Real-time systems are however likely to require dedicated optimized software.
Notable examples include the languages LISP and Prolog, which were invented for AI research but are now used for non-AI tasks. Hacker culture first sprang from AI laboratories, in particular the MIT AI Lab, home at various times to such luminaries as John McCarthy, Marvin Minsky, Seymour Papert (who developed Logo there) and Terry Winograd (who abandoned AI after developing SHRDLU).
A.I. in Myth and Fiction:
In science fiction AI is often portrayed as an upcoming power trying to overthrow human authority, usually in the form of futuristic humanoid robots. Best known examples include the films The Terminator and The Matrix, as well as TV shows such as the re-imagined Battlestar Galactica series. Another common theme is the suspicion and hatred by humanity for AIs and the AIs attempt to gain human acceptance. Films include Bicentennial Man, Artificial Intelligence: A.I. and The Iron Giant. This concept is also explored in the Uncanny Valley hypothesis.
Isaac Asimov wrote stories where engineers understood these potential problems and designed their robots accordingly. Positive examples of AIs include Robby from Forbidden Planet, R2D2, C3PO and Data (Star Trek). A negative example, I, Robot is based on Asimov's stories in which an AI positronic brain develops own radical understanding of the "three laws of robotics." The inevitability of the integration of AI into human society is also argued by some science/futurist writers such as Kevin Warwick and Hans Moravec and the Animation Ghost in the Shell.
ASIMO & AIBO:
Perhaps the most celebrated two non-biological intelligent machines in the today's world are ASIMO and AIBO. ASIMO is a humanoid robot created by Honda Motor Company. ASIMO is an acronym for Advanced Step in Innovative MObility. Honda's official statements indicate that the robot's name is not a reference to science fiction writer and inventor of the Three Laws of Robotics, Isaac Asimov. In Japanese, the name is pronounced ashimo and, not coincidentally, means legs also. With 2000's ASIMO model Honda added many features that enable ASIMO to interact better with humans. These features include- Recognition of moving objects, Recognition of postures and gestures, Environment recognition, Distinguishing sounds and Facial recognition. Utilizing networks such as the Internet, ASIMO can provide information and function better for various commercial applications, such as reception. It can integrate with user's network system and by accessing information via the Internet, ASIMO can, for example, become a provider of news and weather updates.
AIBO - Artificial Intelligence roBOt, is one of several types of robotic pets designed and manufactured by Sony. Able to walk, see its environment via camera and recognize spoken commands, they are considered to be autonomous robots, since they are able to learn and mature based on external stimuli from their owner or environment, or from other AIBOs. AIBOware, is the title given to the software the AIBO runs on its pink Memory Stick. The Life AIBOware allows the robot to be raised from pup to fully grown adult while going through various stages of development as its owner interacts with it. The Explorer AIBOware allows the owner to interact with a fully mature robot able to understand 100 voice commands. Without the AIBOware, the AIBO will run in what is called Clinic Mode and can only perform basic actions. The AIBO has seen use as an inexpensive platform for artificial intelligence research, because it integrates a computer, vision system, and articulators in a package vastly cheaper than conventional research robots. The autonomous soccer competition has a "RoboCup Four-Legged Robot Soccer League" in which numerous institutions from around the world participate. Competitors program a team of AIBO robots to play games of autonomous robot soccer against other competing teams.
Last Words:
Last words about AI is there is no last word. Some people considering it as a threatening to the human kind. The philosopher John Searle thinks that the idea of a non-biological machine being intelligent is incoherent. He proposes the Chinese room argument in this regard. The philosopher Hubert Dreyfus says that AI is impossible. The computer scientist Joseph Weizenbaum says the idea is obscene, anti-human and immoral. Various people have said that since artificial intelligence hasn't reached human level by now, it must be impossible. Just think what will happen if your PC or Laptop or other equipments become more intelligent than you. It raises the common but unsolved question- Then who'll dominate whom?