2. CMSC 100 Artificial Intelligence: Human vs. Machine Professor Marie desJardins Thursday, November 8, 2012 Thu 11/1/12 1 Artificial Intelligence

3. 2 Memory is at the Core (Literally) Remember Hal? “Open the pod bay door, Hal.” “My mind is going...” Memory is at the core of our being (and a computer’s)...but our memories look very different! The first magnetic core memory [www.columbia.edu/acis/history]thebrain.mcgill.ca Thu 11/1/12 Artificial Intelligence

4. 3 Overview What is AI? (and why is it so cool?) AI: Past and Present History of AI AI Today Computational vs. Biological Memory The Skeptics Speak Thu 11/1/12 Artificial Intelligence

5. What is AI? Thu 11/1/12 Artificial Intelligence 4

6. 5 AI: A Vision Could an intelligent agent living on your home computer manage your email, coordinate your work and social activities, help plan your vacations …… even watch your house while you take those well planned vacations? Thu 11/1/12 Artificial Intelligence

7. 6 Main Goals of AI Represent and store knowledge Retrieve and reason about knowledge Behave intelligently in complex environments Develop interesting and useful a pplications Interact with people, agents, and the environment Thu 11/1/12 Artificial Intelligence

8. 7 Foundations of AI Computer Science & Engineering AI Mathematics Cognitive Science Philosophy PsychologyLinguistics Biology Economics Thu 11/1/12 Artificial Intelligence

9. 8 Big Questions Can machines think ? If so, how ? If not, why not ? What does this say about human beings ? What does this say about the mind ? And if we can make machines think, should we ? Thu 11/1/12 Artificial Intelligence

10. History of AI Thu 11/1/12 Artificial Intelligence 9

11. 10 Timeline 1950: Alan Turing proposes the Turing test 1956: Dartmouth conference, “ artificial intelligence ” coined 1958: Lisp programming language for symbolic reasoning created 1965: First expert system (Dendral – chemistry modeling) 1969: SRI’s Shakey the robot: perception and problem solving 1971: BKG backgammon program defeats the world champion 1997: Deep Blue defeats Garry Kasparov, world chess champion 2007: Checkers is solved (unbeatable program created) 2012: Watson beats Jeopardy! champions Ken Jennings and Brad Rutter Thu 11/1/12 Artificial Intelligence

12. 11 Early AI: Eliza ELIZA: A program that simulated a psychotherapist interacting with a patient and successfully passed the Turing Test Implemented at MIT during 1964-1966 by Joel Weizenbaum First script was DOCTOR Simple pattern-matching Each pattern had an associated reply which might include bits of the input (after simple transformations (my  your) Weizenbaum was shocked at reactions Psychiatrists thought it had potential People unequivocally anthropomorphized Let me tell you my problems... Many thought it solved the natural language problem!! Thu 11/1/12 Artificial Intelligence

13. 12 Eliza Speaks I am the psychotherapist. Please, describe your problems. i'm having a hard time with my students Why do you say that? well, they keep asking me for money Maybe your plans have something to do with this. what plans? Is it because of your life that you say what plans? No, it's because I didn't know what you were talking about Is it because you didn't know what I was talking about that you came to me? no, it's because i wanted to see if you could pass the turing test Does it bother you that you wanted to see if I could really pass the turing test? ….. How do you reconcile problems at school? This is a waste of time. Good bye My secretary will send you a bill. Thu 11/1/12 Artificial Intelligence

14. 13 Early AI: Parry Kenneth Colby modeled a paranoid using the same techniques as Eliza, around 1968 PARRY has basic emotions. If it gets angry, its replies become more hostile In a Turing test, expert psychiatrists were unable to distinguish PARRY’s ramblings from those of real paranoids Thu 11/1/12 Artificial Intelligence

15. 14 PARRY Speaks Good afternoon. My name is Doctor Jones. Pleased to meet you. How are you? All right I guess. Could you tell me your name? Pat Smith. I though you might have some problems. I've been upset lately. By what? People get on my nerves sometimes. Tell me more. Do you know anything about bookies?... Thu 11/1/12 Artificial Intelligence

16. 15 P: I don't understand your motives. E: Why don't you understand my motives? P: Shouldn't I be? E: Why do you say that just now? P: That's just the way it is. E: Suppose that's the way it were not. P: So? E: I am not sure I understand you fully. P: You harp on the same questions too much. E: What does that similarity suggest to you? P: I don't get you. E: Do you wish that you did get I? Thu 11/1/12 Artificial Intelligence

17. 16 Turing Test Three rooms contain a person, a computer, and an interrogator The interrogator can communicate with the other two by “teleprinter” (or, say, AIM) The interrogator tries to determine which is the person and which is the machine The machine tries to fool the interrogator into believing that it is the person If the machine succeeds, then we conclude that the machine can think Thu 11/1/12 Artificial Intelligence

18. 17 The Loebner Contest A modern version of the Turing Test, held annually, with a $100,000 cash prize Hugh Loebner was once director of UMBC’s Academic Computing Services (née UCS, lately OIT) http://www.loebner.net/Prizef/loebner-prize.html Participants include humans, computers (chatbots), and judges Scoring Rank from least human to most human Highest median rank wins $2000 If better than a human, win $100,000 (Nobody yet…) 2012 winner: Chip Vivant, http://www.chipvivant.com/ Thu 11/1/12 Artificial Intelligence

19. 18 What’s Easy and What’s Hard? It’s been easier to mechanize many of the high-level tasks we usually associate with “intelligence” in people e.g., symbolic integration, proving theorems, playing chess, medical diagnosis It’s been very hard to mechanize tasks that lots of animals can do walking around without running into things catching prey and avoiding predators interpreting complex sensory information (e.g., visual, aural, …) modeling the internal states of other animals from their behavior working as a team (e.g., with pack animals) Is there a fundamental difference between the two categories? Thu 11/1/12 Artificial Intelligence

20. AI Today Thu 11/1/12 Artificial Intelligence 19

21. 20 Who Does AI? Academic researchers (perhaps the most Ph.D.-generating area of computer science in recent years) Some of the top AI schools: CMU, Stanford, Berkeley, MIT, UIUC, UMd, U Alberta, UT Austin,... (and, of course, UMBC!) Government and private research labs NASA, NRL, NIST, IBM, AT&T, SRI, ISI, MERL,... Lots of companies ! Thu 11/1/12 Artificial Intelligence

22. Computational vs. Biological Memory Thu 11/1/12 Artificial Intelligence 21

23. 22 How Does It Work? (Humans) Basic idea: Chemical traces in the neurons of the brain Types of memory: Primary (short-term) Secondary (long-term) Factors in memory quality: Distractions Emotional cues Repetition Thu 11/1/12 Artificial Intelligence

24. 23 How Does It Work? (Computers) Basic idea: Store information as “bits” using physical processes (stable electronic states, capacitors, magnetic polarity,...) One bit = “yes or no” Types of computer storage: Primary storage (RAM or just “memory”) Secondary storage (hard disks) Tertiary storage (optical jukeboxes) Off-line storage (flash drives) Factors in memory quality: Power source (for RAM) Avoiding extreme temperatures Size Speed Thu 11/1/12 Artificial Intelligence

25. 24 Measuring Memory Remember that one yes/no “bit” is the basic unit Eight (2 3 ) bits = one byte 1,024 (2 10 ) bytes = one kilobyte (1K) * 1,024K (2 20 bytes) = one megabyte (1M) 1,024K (2 30 bytes) = one gigabyte (1G) 1,024 (2 40 bytes) = one terabyte (1T) 1,024 (2 50 bytes) = one petabyte (1P)... 2 80 bytes = one yottabyte (1Y?) * Note that external storage is usually measured in decimal rather than binary (1000 bytes = 1K, and so on) Thu 11/1/12 Artificial Intelligence

26. 25 Showdown Computer capacity: Primary storage: 64GB Secondary storage: 750GB (~10 12 ) Tertiary storage: 1PB? (10 15 ) Computer retrieval speed: Primary: 10 -7 sec. Secondary: 10 -5 sec. Computing capacity: 1 petaflop (10 15 floating-point instructions per second), very special purpose Digital Extremely reliable Not (usually) parallel Human capacity: Primary storage: 7 ± 2 “chunks” Secondary storage: 10 8432 bits?? (or maybe 10 9 bits?) Human retrieval speed: Primary: 10 -2 sec Secondary: 10 -2 sec Computing capacity: possibly 100 petaflops, very general purpose Analog Moderately reliable Highly parallel Thu 11/1/12 Artificial Intelligence

27. 26 It’s Not Just What You “Know” Storage Indexing Retrieval Inference Semantics Synthesis...So far, computers are good at storage, OK at indexing and retrieval, and humans win on pretty much all of the other dimensions...but we’re just getting started Electronic computers were only invented 60 years ago! Homo sapiens has had a few hundred thousand years to evolve... Thu 11/1/12 Artificial Intelligence

28. The Skeptics Speak Thu 11/1/12 Artificial Intelligence 27

29. 28 Mind and Consciousness Many philosophers have wrestled with the question: Is Artificial Intelligence possible? John Searle: most famous AI skeptic Chinese Room argument Is this really intelligence? ? ! Thu 11/1/12 Artificial Intelligence

30. 29 What Searle Argues People have beliefs; computers and machines don’t. People have “intentionality”; computers and machines don’t. Brains have “causal properties”; computers and machines don’t. Brains have a particular biological and chemical structure; computers and machines don’t. (Philosophers sometimes make claims like “People have intentionality” without actually saying what “intentionality” is, except (in effect) “the stuff that people have and computers don’t.”) Thu 11/1/12 Artificial Intelligence

31. 30 Let’s Introspect For a Moment... Have you ever learned something by rote that you didn’t really understand? Were you able to get a good grade on an essay where you didn’t really know what you were talking about? Have you ever convinced somebody you know a lot about something you really don’t? Are you a Chinese room?? What does “understanding” really mean? What i s intentionality? Are human beings the only entities that can ever have it? What is consciousness? Why do we have it and other animals and inanimate objects don’t? (Or do they?) Thu 11/1/12 Artificial Intelligence

32. 31 Just You Wait... Thu 11/1/12 Artificial Intelligence