I Cannot Add Students to Course Unfortunately this class is oversubscribed I cannot add new students to the course CS 416 Artificial Intelligence Potential exception for 4th year CS Majors Feel free to stay through end of course today Lecture 1 Introduction Textbook Syllabus This is a great book Instructor David Brogan Olsson 217 982 2211 dbrogan cs virginia edu 2 nd edition released one month ago Most widely used in U S universities It s so good Office hours Wednesday 1 30 3 00 I m going to make you read it T A Ben Hocking Homework Office hours TBA Read chapters 1 and 2 Syllabus What is AI Class web page Discussion exercise for class Soon to be at http www cs virginia edu cs416 Think of example AI systems applications that are intelligent Grading 3 perhaps 4 programming assignments 40 A couple homework assignments 10 Midterm and Final 25 for each Think of example AI Techniques Page 1 AI Systems AI Techniques Thermostat Tic Tac Toe Your car Chess Google Babblefish Rule based Fuzzy Logic Neural Networks Genetic Algorithms This thing Asimo How to Categorize These Systems Distinctions Systems that think like humans Systems that act like humans How one thinks vs How one acts How can I know how you think For the most part you are a black box Cognitive Science Systems that think rationally Systems that act rationally How can I know how you act Observation Turing Test Alan Turing Building a Brain Rational vs Human World War II motivated computer advances Thinking acting rationally vs Thinking acting like a human Code breaking Colossus Computing missile trajectories Mark I Electronic Numerical Integrator and Computer ENIAC Rely on logic rather than human to measure correctness Thinking rationally logically Socrates is a human All humans are mortal Socrates is mortal Logic formulas for synthesizing outcomes Turing greatly involved with British efforts to build computers and crack codes Bletchley Park Acting rationally logically Arrested for being a homosexual in 1952 and denied security clearance Committed suicide in 1954 Even if method is illogical the observed behavior must be ratio nal Page 2 Perspective of this Course What is AI We will investigate the general principles of rational agents The use of computers to solve problems that previously could only be solved by applying human intelligence thus something can fit this definition today but once we see how the program works and understand the problem we will not think of it as AI anymore David Parnas Not restricted to human actions and human environments Not restricted to human thought Not confined to only using laws of logic Anything goes so long as it produces rational behavior Foundations Philosophy Foundations Mathematics More formal logical methods Aristotle 384 B C E Author of logical syllogisms da Vinci 1452 designed but didn t build first mechanical calculator Descartes 1596 can human free will be captured by a machine Is animal behavior more mechanistic Necessary connection between logic and action is discovered Boolean logic Boole 1847 Analysis of limits to what can be computed Intractability 1965 time required to solve problem scales exponentially with the size of problem instance NP complete 1971 Formal classification of problems as intractable Uncertainty Cardano 1501 The basis for most modern approaches to AI Uncertainty can still be used in logical analyses Foundations Economics Foundations Neuroscience How do brains work Humans are peculiar so define generic happiness term utility Early studies 1824 relied on injured and abnormal people to understand what parts of brain do More recent studies use accurate sensors to correlate brain acti vity to human thought Game Theory study of rational behavior in small games Operations Research study of rational behavior in complex systems Herbert Simon 1916 2001 AI researcher who received Nobel Prize in Economics for showing people accomplish satisficing solutions those that are good enough By monitoring individual neurons monkeys can now control a computer mouse using thought alone Moore s law states computers will have as many gates as humans have neurons in 2020 How close are we to having a mechanical brain Parallel computation remapping interconnections binary vs gradient Page 3 Foundations Psychology Foundations Control Theory Helmholtz and Wundt 1821 started to make psychology a science by carefully controlling experiments The brain processes information 1842 Machines can modify their behavior in response to the environment sense action loop Water flow regulator 250 B C E steam engine governor thermostat The theory of stable feedback systems 1894 stimulus converted into mental representation cognitive processes manipulate representation to build new representations new representations are used to generate actions Build systems that transition from initial state to goal state with minimum energy In 1950 control theory could only describe linear systems and AI largely rose as a response to this shortcoming Cognitive science started at a MIT workshop in 1956 with the publication three very influential papers Foundations Linguistics History of AI Speech demonstrates so much of human intelligence Read the complete story in text Alan Turing 1950 did much to define the problems and techniques John McCarthy helped coordinate the players 1956 Alan Newell and Herbert Simon 1956 did much to demonstrate first solutions Marvin Minsky student of von Neumann built a neural network 1951 from 3000 vacuum tubes and the autopilot from a B 24 bomber Analysis of human language reveals thought taking place in ways not understood in other settings Children can create sentences they have never heard before Language and thought are believed to be tightly intertwined Why is AI in Computer Science History of AI 1952 1969 Uses computer as a tool more than psychologists mathematicians operations research or mechanical engineers control theory Great successes Logic programs were replicating human logic in many cases Solving hard math problems game playing LISP was invented by McCarthy 1958 second oldest language in existence could accept new axioms at runtime McCarthy went to MIT and Marvin Minsky started lab at Stanford Both powerhouses in AI to this day Page 4 History of AI 1966 1973 AI History 1969 1979 Knowledge based Systems A dose of reality Overhyped Systems fail to play chess and translate Russian Previous systems knocked because general logical algorithms could not be applied to realistic