2. Memory is at the Core (Literally)
• Memory is at the core of our being (and a
computer’s)
• ...but our memories look very different!
2
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
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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?
5
6. Main Goals of AI
• Represent and store knowledge
• Retrieve and reason about knowledge
• Behave intelligently in complex environments
• Develop interesting and useful applications
• Interact with people, agents, and the environment
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7. Foundations of AI
Computer
Science &
Engineering
Mathematics Philosophy
Economics
AI Biology
Psychology Cognitive Linguistics
Science
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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, can
we?
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11. 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?
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13. 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!
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14. Applications
• A sample from the 2008 International Conference
on Innovative Applications of AI:
– Event management (for Olympic equestrian
competition)
– Language and culture instruction
– Public school choice (for parents)
– Turbulence prediction (for air traffic safety)
– Heart wall abnormality diagnosis
– Epilepsy treatment planning
– Personalization of telecommunications services
– Earth observation flight planning (for science data)
– Crop selection (for optimal soil planning)
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15. What Can AI Systems Do Now?
Here are some example applications:
• Computer vision: face recognition from a large set
• Robotics: autonomous (mostly) automobile
• Natural language processing: simple machine translation
• Expert systems: medical diagnosis in a narrow domain
• Spoken language systems: ~2000 word continuous speech
• Planning and scheduling: Hubble Telescope experiments
• Learning: text categorization into ~1000 topics
• User modeling: Bayesian reasoning in Windows help (the infamous paper
clip…)
• Games: Grand Master level in chess (world champion), checkers,
backgammon, etc.
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19. What CaN’t aI systEMs dO
(Yet)?
• Understand natural language robustly (e.g.,
read and understand articles in a newspaper)
• Surf the web (or a wave)
• Interpret an arbitrary visual scene
• Learn a natural language
• Play Go well
• Construct plans in dynamic real-time domains
• Refocus attention in complex environments
• Perform life-long learning
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21. 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
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22. 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:
Size Speed
– 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
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23. MOOrE’s LaW
• Computer memory (and processing speed,
resolution, and just about everything else)
increases exponentially
26
24. 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...
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26. 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?
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27. 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 can make claims like “People have
intentionality” without ever really saying what
“intentionality” is, except (in effect) “the stuff that people
have and computers don’t.”)
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28. 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 is 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?)
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