Introduction to AI - Week 1 box Introduction to Artificial Intelligence 06-08775 Manfred Kerber School of Computer Science The University of Birmingham Birmingham, B15 2TT, England e-mail: M.Kerber@cs.bham.ac.uk, Office: 137 http://www.cs.bham.ac.uk/ mmk/Teaching/AI [crest.jpg] _________________________________________________________________________________________________________ Artificial Intelligence - The Dream - * Dreams in science and technology * Calculators and the computer * Understanding the mind * Welcome to the machine - Science fiction _________________________________________________________________________________________________________ Dreams in Science and Technology * Flying, Travel to other planets/solar systems, * Immortality, health, superhuman power, * Understanding the physical structure of the universe, * Utopia, a just, peaceful, wealthy society * Build machines that do the work for us * Understanding ourselves, our origins, our thinking, our wishes _________________________________________________________________________________________________________ Calculators - Schickard, Pascal, Leibniz [schickard-calc.jpg] [schickard-skizze.jpg] [pascal-calculator.jpg] Wilhelm Schickard (1592-1635) Blaise Pascal (1623-1662) The dream of the automation of computation - partly realised _________________________________________________________________________________________________________ The Dream of a Universal Computer Charles Babbage and Ada Lovelace [babbage.jpg] [ada.jpg] Charles Babbage (1792-1871) Ada Lovelace (1815-1852) _________________________________________________________________________________________________________ Difference Engine/Analytical Engine [diffeng.jpg] [diff-eng.jpg] The dream of a universal computing machine, almost realised _________________________________________________________________________________________________________ Science or Mystery? [mind.jpg] [universe-in-head.jpg] Robert Fludd (1574-1637): Universe as a mixture of opposite principals (like light and darkness, sympathy and antipathy) _________________________________________________________________________________________________________ Understanding the Mind [ventrikel.jpg] Ventricle theory of 1524, First attempts to locate cognitive abilities in regions of the brain. _________________________________________________________________________________________________________ Understanding the Mind (Cont'd) [descartes-fire.jpg] René Descartes' (1596-1650) description in "Traité de l'Homme" to explain reflex actions. The long fiber running from the foot to the cavity in the head is pulled by the heat and releases a fluid that makes the muscles contract. _________________________________________________________________________________________________________ Understanding the Mind (Cont'd) [phrenology1.jpg] Phrenology, localisation of mental functions in the brain Introduced by Franz Joseph Gall (1758-1828) picture from his disciple Johann Kaspar Spurzheim (1776-1832) _________________________________________________________________________________________________________ Intelligent Machines - Fakes Speech [sprachmachine.jpg] Dream: Build intelligent machines that can speak! (Entertainment) _________________________________________________________________________________________________________ Intelligent Machines - Fakes Chess [chess.jpg] Build intelligent machines that can play chess! Kempelen's chess playing Turk (1768) _________________________________________________________________________________________________________ Predicting the Future [laplace1.jpg] Pierre Simon Laplace (1749-1827) Laplace's Demon Build a super-human intelligence which is able to compute all of the world (past, present, and future) if only it knows for a single point in time the positions and speeds of all particles in the universe. _________________________________________________________________________________________________________ Science Fiction - Building Companions [robot.jpg] Karel Capek (1890-1938), robota = forced labour. Build intelligent machines that can work for you! Asimov's Robot Laws: 1. A robot must not harm a human being or allow by inactiveness that a human being is harmed. 2. A robot must obey to orders given by a human being unless the execution of the order is in conflict with law 1. 3. A robot must protect its own existence, unless this is in conflict with laws 1 or 2. _________________________________________________________________________________________________________ AI = Build Machines that Behave as in the Movies [metropolis.jpg] [2001.jpg] [starwars.jpg] Metropolis 2001 (HAL) Star Wars (R2-D2) _________________________________________________________________________________________________________ Literature [books-shelf1.jpg] * Artificial Intelligence: A New Synthesis, Nils J. Nilsson, Morgan Kaufmann 1998. * Artificial Intelligence - A Modern Approach, Stuart Russell & Peter Norvig, Prentice Hall, 2nd edition. * Artificial Intelligence, 3rd Edition, Patrick Henry Winston, Addison-Wesley, 1992. * Artificial Intelligence, 2nd Edition, Elaine Rich & Kevin Knight, McGraw Hill 1991. _________________________________________________________________________________________________________ Artificial Intelligence - The Roots - * Logic * Philosophy * Computation * Biology/Neuroscience * Psychology * ... _________________________________________________________________________________________________________ Logic [Aristotle.jpg] Aristotle (384-322 B.C.) Codify different styles of deductive reasoning by so-called syllogisms, e.g. Modus Ponens A A -> B -------- ------------- ------------- B Read: For any statements A and B holds: if A is true and A implies B is true then B is true. Or more concretely: It's raining If it's raining then the street gets wet -------- ------------- ------------- The street gets wet _________________________________________________________________________________________________________ The Idea of the Mechanisation of Logic [Lullus.jpg] Raimundus Lullus (1235-1316) Ars Magna: Try to build a machine which can answer all questions, in form of wheels like: [lullus-disk1.jpg] [lullus-disk2.jpg] _________________________________________________________________________________________________________ Regulae ad directionem ingenii [descartes.jpg] René Descartes (1596-1650) * translate any problem into a mathematical problem * transform any mathematical problem into a system of equations * translate any system of equations into one equation * solve this one equation (Carried through for geometry by analytical geometry) Mind-body separation _________________________________________________________________________________________________________ Calculemus = Let's calculate [leibniz.jpg] Gottfried Wilhelm Leibniz (1646-1716) * Lingua characteristica universalis: Find a universal language which can be used to represent any problem * Calculus ratiocinator: Can solve any problem automatically (without dispute): Calculemus Interest linked to the development of calculator Leibniz invented the dual representation of numbers _________________________________________________________________________________________________________ The Laws of Thought [boole.jpg] George Boole (1815-1864) * Foundations of propositional logic * Investigate the algebraic laws of logic, e.g.: A & A <-> A (i.e., A and A is the same as A) * purpose: "to collect ... some probable intimations concerning the nature and constitution of the human mind." (Boolean Algebra, Boolean values in computer science) _________________________________________________________________________________________________________ Special Reasoning Machines [demonstrator.jpg] Earl Stanhope's Logic Demonstrator, 1777 * machine for solving syllogisms, numerical problems in in logical form, elementary questions of probability. [jevons-logic-machine.jpg] William Jevons' Logic Machine, 1869 * Machine for Boolean algebra and Venn diagrams, able to solve logical problems faster than human beings _________________________________________________________________________________________________________ Classical Logic [frege.jpg] Gottlob Frege (1848-1925) * Begriffsschrift, foundations of classical logic [russell.jpg] Bertrand Russell (1872-1970) * Paradoxes, types, principia mathematica _________________________________________________________________________________________________________ Strength and Limitations of Classical Logic [goedel.jpg] Kurt Gödel (1906-1978) * Completeness of first-order logic, that is, any reasoning whether something is a logical consequence of something else can be mechanised in this powerful reasoning system * Incompleteness of sufficiently rich logic, there are truths which do not have a finite proof _________________________________________________________________________________________________________ Modern Computers [turing.jpg] Alan Turing (1912-1954) * What can be computed by a computer? - Halting problem Turing test for intelligence [neumann.jpg] John von Neumann (1903-1957) * von Neumann architecture: give a description that is independent from the particular realisation of a computer _________________________________________________________________________________________________________ The Role of Logic * McCarthy: The relationship between computation and math. logic will be as fruitful as that between physics and analysis * Logic as powerful knowledge representation formalism * Logical reasoning as a model for human reasoning * Mechanisation of reasoning by logical rules * Extensions to logic necessary for adequate reasoning: + probabilistic reasoning + fuzziness + non-monotonicity (revision of judgements) + non-deductive reasoning (analogy, induction, abduction) symbolic representation of knowledge _________________________________________________________________________________________________________ Brain science - Neuroscience * Brain (vs heart) as seat of the soul and the mind * Understand the function of the brain + ventricle theory (ventricles = empty parts of the brain do the job) + brain as a big gland + phrenology (which part does what) + understand brain as a highly connected set of neurons, 10^10 neurons with each 100 connections on average + neuron as a digital entity which either does or does not fire depending whether an activation threshold is exceeded or not _________________________________________________________________________________________________________ Brain science - Neuroscience (Cont'd) [dbrain.jpg] [dbody.jpg] Gives raise to neural nets, subsymbolic representation of knowledge _________________________________________________________________________________________________________ Psychology [freud1.jpg] Sigmund Freud (1856-1939) * Founder of psychoanalysis * Try to understand the psyche * Try to understand motivations as well as anomalies of human behaviour/human mind/human soul (clues to mental activity/conflicts) * The conscious vs the unconscious * Psychoanalysis Relationship between psychology - cognitive science - artificial intelligence _________________________________________________________________________________________________________ Darwinism [darwin.jpg] Charles Darwin (1809-1882) * "On the origin of species by means of natural selection" * different species develop by natural selection * cross-over and random mutation * survival of the fittest (only the fit ones mate and reproduce) What does it mean to be "fittest"? Gives raise to evolutionary computation (rather than programming, breed programs) _________________________________________________________________________________________________________ Summary * Different origins of AI: philosophy, logic, computation, psychology, biology * In this module we follow mainly the logical/computational origins: symbolic representation of knowledge Reading [books-shelf1.jpg] * Introduction chapters in the AI books * The story of Cybernetics, Maurice Trask, Studio Vista, 1971. * Minds, Brains & Computers, edited by R. Morelli et al., Ablex Publ., 1992. * Gehirn, Bewusstsein und Erkenntnis, E. Oeser, Franz Seitelberger, Wissenschaftliche Buchgesellschaft, 1988. _________________________________________________________________________________________________________ _________________________________________________________________________________________________________ © Manfred Kerber, 2004, Introduction to AI 24.4.2005 The URL of this page is http://www.cs.bham.ac.uk/~mmk/Teaching/AI/Teaching/AI/l1.html. URL of module [1]http://www.cs.bham.ac.uk/~mmk/Teaching/AI/ References 1. http://www.cs.bham.ac.uk/~mmk/Teaching/AI/