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ARTIFICIAL INTELLIGENCE
A Gentle, Jargon-Free Introduction
K. RaghunathanChartered Engineer
FIETE, MIE, MCSI, MISTE, MISTD, MIIMMRetd Dy Controller (R&D)
Section 1
What is AI ?
• Study/Science of –Intelligent Machines
–Making Machines Intelligent
AI & Computers
• Computers seem to have some Intelligence– Solve Math problems [Arithmetic, Algebra, Calculus,
Geometry etc]– Do text processing– Control Eqpt & Processes in Industry– Communicate
• Natural Belief : computers can be made more intelligent
• So, AI is considered a Branch of Computer Science
Machines & Humans
• Right from Cavemen, humans are inventing new Tools, Instruments & Machines– To do all our hard work– Even for entertainment– To reduce/avoid our physical/mental strain
Human Tasks
• What are our everyday tasks ?
– Professional
– Personal
Functions of our Sensory Organs
• Eye– See
• Ear– Hear
• Tongue / Mouth– Taste, Speak
• Nose– Smell, Breathe
• Skin / Limbs– Feel, do Physical Work – Walk, Climb, Lift, Throw, Eat etc
Sixth Sense
• Comprehend [Understand]– Vision– Language
• Remember
• Plan
• Decide
• Learn
• Emote
Brain & Mind
• Concrete & Abstract
• Tangible & Intangible
• Similar to Computer
• Like Hardware & Software
What we still do ourselves ?
• Logical Thinking & Reasoning
• Making wise decisions – often with Incomplete, Vague & Uncertain
facts at hand
AI attempts to fill this gap
Intelligent Machines
• Machines that can– Think– Decide– Solve– Plan– Learn
• Thinking Machines
• Artificial Intelligence
Can Machines Think ?
• Some believe so & some don’t
• What Level of Intelligence will make a Machine qualify as Intelligent Machine or Thinking Machine ?
• The Turing Test
The Turing Test
The Turing Test
• A machine can be deemed intelligent
• If it can make a human think that
• he/she is talking to a human
• & not to a machine
Intelligent Machines
• A machine can be considered Intelligent
• if it can solve complex problems
• requiring a high level of intelligence
• normally found only in human beings
AI – Science or Art ?• Science
– Multi-disciplinary & Inter-disciplinary
• Art– Very Intricate Fine Art– Like Painting & Sculpting
• Science– involves designing machines
• Art– involves programming
Inputs to AI
• Maths [Symbolic Logic]• Physiology [Working of Body Parts of Living
Organisms] • Philosophy & Psychology [Human Logic &
Behaviour]• Cognitive Science [Perception, Understanding]• Cybernetics [Communication & Control in
Animals & Machines]• Electronics [Making Machines]• Computer Science [Programming the Machine's
Behaviour]
AI’s Output
• Used by almost all Sciences– Including Computer Science
• Maximum dependency on AI– Robotics & Neural Networks– Considered part of AI
Section 2
Back to Square One
What is Intelligence ?
Let us have your Opinions please
Intelligence
• Abstract
• Eludes accurate, comprehensive definition
• Easier to understood than to define
• Seems to be directly proportional to Knowledge
Intelligence (cont’d)
• The Albert Einstein Anecdote
Intelligence (contd)
• Knowledge [Lots of it !]
• Ability to put knowledge to use
• Pertains to what we can do with our 5 Senses
• Pertains more to what we can do with our 6th Sense !
What is Knowledge ?
Anybody wish to define ?
Knowledge
• Abstract
• Eludes accurate, comprehensive definition
• Easier to understand than to define
• AI has to deal with various aspects of Knowledge
Knowledge (contd)
• Classification• Representation [including Storage in
Computer Memory]• Acquisition [Learning]• Manipulation
– Searching & Matching – Reasoning [Inference, Drawing Conclusions,
Decision Making, Problem Solving]
• Planning
Classification of Knowledge
• Factual or Procedural
• Certain or Uncertain
• Consistent or Inconsistent [vary with time, place, person or situation]
• Well-Defined [Crisp] or Vague [Fuzzy]
• Complete or Incomplete [Partial]
Reasoning Techniques
• Depend on the Type of Knowledge being dealt with
• Certain, consistent & crisp : Predicate Logic
• Uncertain : Probablistic Reasoning• Inconsistent : Truth Maintenance Systems• Fuzzy : Fuzzy Logic• Partial : Statistical & Probablistic
Reasoning
Reasoning Techniques (cont’d)
• Ad hoc Methods
– Closed World Assumption– Circumscription– Abductive Reasoning– Modal & Temporal Logics
Learning Methods
• By Rote [by Reading]
• By being Taught
• From Experience
• By Analogy [From Examples]
• By Drawing Conclusions– From other known Facts
What Humans are Good at
An Interactive Experiment
1
2
What Humans are Good at
• Humans seem to be good at – Reasoning with Uncertain, Fuzzy & Partial
Knowledge– Learning from Experience & Examples
• AI Research pays more attention to these Areas
AI Techniques
• Procedures & Algorithms employed in AI• Compared to those used in other Sciences
– Not merely Formulae– Use different approaches– More efficient, effective & intelligent– Profuse use of Heuristics
• Heuristic– “Educated Guess”– Born out of Past Experience
Heuristics
- An Interactive Experiment
[opening a book at a desired page]
Heuristic Search Techniques
• Many Methods available
• Most Noteworthy are:– A*– MiniMax with Alpha-Beta Pruning
Expert Systems&
Decision Support Systems
• A Speciality of AI
• Very High Level of Intelligence & Domain Knowledge
• a Level normally found only in Experts in that Field
Expert Systems
Knowledge
Base
Search
Engine
Match
Logic
Inference
Logic
User
Inter
face
Query
Response
Section 3
Miscellaneous Topics
• Miscellaneous, but nevertheless Essential
• Automation– Useful in Hazardous Environs
• Computer Vision– Object Recognition
• Natural Language Processing• Pattern Recognition & Pattern Classification
– Data Mining, Image Processing• Guide/Help/Rescue• Weather/Business Forecasting• Neural Networks
Vision
• Object Recognition
• Range Estimation
• Emotion Recognition
Natural Language Processing
• Vocabulary
• Ambiguity– Human Languages are Context-Sensitive– One word having many meanings– Many words having same/similar meaning– Accent varies from place to place
• Real Life Examples
• Feelings/Emotions
AI Milestones
• Too many to list here
• Early days of AI– Mycin - Medical Diagnosis– R - Design of Computer HW Architecture– Deep Blue - Chess Champion– Eliza - Conversationist– Racter - Writes Books
AI Milestones (2)
• Modern days:
• Expert Systems & Decision Support Systems in a wide range of fields– especially Medicine, Finance & Entertainment
• Wide range of Medical Eqpt - CAT Scan etc• Analysis & Prediction - Economics, Stockmarket,
Agriculture, Genetics, Elections• 3D Computer Games & Walk-throughs• Helpful Robots - Rescue, Operating in
Hazardous environments
AI Milestones (3)
• Spell-Check & Word Completion
facility in Text Processing Programs
• Voice Commands to open/close files etc
• Programs to read text, to teach Languages
• 3D & Walk-Through Games/Presentations
Basic Hurdle• Intelligent Machine = Thinking Machine
• To make a machine think, act & react like a human:
• We should first understand how humans think, act & react
• Why a person thinks, acts & reacts in a particular way
• Why different persons think, act & react differently
• Why same person thinks, acts & reacts differently at different times, even if situations are similar
Basic Hurdle (cont’d)
• Real life examples– Bernard Shaw & Isadora Duncan Episode– Once I took my wife to a movie ….
Basic Hurdle (cont’d)
• Unfortunate Reality for AI scientists • God Almighty has a habit of making
humans – so varied, – so un-understandable – so unpredictable !
• Given such a starting point– How are we going to make machines that
would behave like humans ?
Basic Hurdle (cont’d)
• Everyone says “AI is a difficult subject".– Not only Students, even Faculty say so– except the Enthusiastic & Optimistic AI
Researcher, of course
• The Ground Reality is:– Humans are so difficult to understand !
• WE are our own Hurdles !
Concluding Remarks
• In spite of the Enormity of the Obstacles, AI marches ahead, relentlessly
• The progress is slow• New Findings & Achievements are Sporadic, few
& far between• But that is no reason to lose hope
– We have achieved many things, which were once considered impossible
– We have set foot on the Moon
• Let us hope that one day we will see The Ultimate Intelligent Machine
Any Questions ?
Thank You !