Transcript M263: Building Blocks of Software

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M366: Natural and artificial
intelligence
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8 credits course, one semester
Pre-requisite course: M263
Two TMAs (20%), one MTA(30%) and one final
exam (50%)
Like any other AOU course, to pass the course you
have to get:
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A Minimum of 40% on the CA (TMA and MTA)
A Minimum of 40% on the final exam
A Minimum of 50% for the average of the CA and the
final
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Course Structure
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The course is divided into six blocks
A total of 17 units
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Block 1: intelligent machines
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Unit 1
Machines, minds and computers
Block 2: Symbolic intelligence
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Unit 1
Unit 2
Unit 3
Unit 4
Fundamentals of symbolic AI
Search
Symbolic AI in the world
Has symbolic AI failed
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Course Structure: the units
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Block 3: Natural intelligence
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Unit 1
Natural intelligence
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Unit 2
Mechanism of natural intelligence
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Unit 3
Interaction and emergence in swarms
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Unit 4
Interaction, emergence, adaptation and selection in
individuals
Block 4: Neural networks
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Unit 1
Mechanism
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Unit 2
Layers and learning
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Unit 3
Unsupervised learning in layers and lattices
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Unit 4
It’s about time: recurrence, dynamics and chaos
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Course Structure: the units
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Block 5: Evolutionary computation
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Unit 1
Unleashing the gene genie, an introduction to
evolutionary algorithms
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Unit 2
Genetic algorithms
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Unit 3
Artificial evolution
Block 6: Reflections
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Unit 1
Intelligence, mind and consciousness
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Block I, Unit 1 Machines, minds and
computers
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This unit has two main aims:
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Reviewing the development of
human thinking about machines and
our mental ability
Presenting historical and technical
issues that lead to Cybernetics and
Symbolic AI
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Block I, Unit 1 Machines, minds and
computers
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This unit focuses on:
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Machines
Minds
Artificial intelligence
Computers
Block I, Unit 1 Machines
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The early beginning: Hephaestus (god of fire) in the
old Greek, created Talos, a gigantic mechanical man
of bronze, guardian of Crete. (Iliad, XVIII)
Automata (around 1495), Leonardo da Vinci
constructed an automaton in the form of armored man
capable of moving its arms and simulating speech.
Vaucanson’s duck (1800’s)
Game-playing automata: the Turk (1770), Deep blue
of IBM 1997)
Robots
Block I, Unit 1 Machines
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Why build such artificial entities?
What sort of thing did people think these entities
actually were?
What has been the public attitude to the idea of
artificial creatures?
Inspired by myths and early creatures, mechanical
pictures start to appear by thinkers of the 17th and the
18th centuries
Block I, Unit 1 Machines
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An intellect which at a certain moment would know all forces that
set nature in motion, and all positions of all items of which nature is
composed, if this intellect were also vast enough to submit these
data to analysis, it would embrace in a single formula the
movements of the greatest bodies of the universe and those of the
tiniest atom; for such an intellect nothing would be uncertain and
the future just like the past would be present before its eyes.
Source: Laplace, Celestial Mechanics (1799–1825)
Block I, Unit 1 Minds
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What is mind ?
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Mind and body: Debate between monist and dualist
Thomas Hobbes (1588-1679):
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The world consists only of particles of matter in motion.
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Bodies and minds are also just particles of matter in motion.
Their motions are caused, in part, by the effects of the
movements of particles outside the body, which press on the
senses, causing particles in our minds to move in sympathy.
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The particles in our minds form parcels: that is, symbols
representing concepts such as number, time, names, and so on.
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Thought amounts to a form of computation, in which these
mental symbols are added, subtracted, etc., in processes similar
to those of arithmetic.
Block I, Unit 1 Cybernetics
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Cybernetics: definitions
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"a science concerned with the study of systems of any nature which are capable of
receiving, storing, and processing information so as to use it for control"-A.N.
Kolmogorov
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"Cybernetique= the art of growing"--A.M. Ampere
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"the science of control and communication in the animal and the machine"-Norbert
Wiener
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"the art of securing efficient operation"-L. Couffignal
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"the art of steersmanship"; "deals with all forms of behavior in so far as they are
regular, or determinate, or reproducible"; "stands to the real machine-electronic,
mechanical, neural, or economic-much as geometry stands to a real object in our
terrestrial space"; "offers a method for the scientific treatment of the system in which
complexity is outstanding and too important to be ignored"-W. Ross Ashby
Block I, Unit 1 Cybernetics
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Cybernetics: definitions
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“a branch of mathematics dealing with problems of control, recursiveness, and
information"-Gregory Bateson
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"the science of effective organization"-Stafford Beer
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"the art and science of manipulating defensible metaphors"-Gordon Pask
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"Should one name one central concept, a first principle, of cybernetics, it would
be circularity."-Heinz von Foerster
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"a way of thinking"-Ernst von Glasersfeld
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"the science and art of understanding"-Humberto Maturana
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"Cybernetics: when I reflect on the dynamics of observed systems and on the
dynamics of the observer-whence 'creative cybernetics': when I project the
dynamics of a system I would like to observe"-from announcement of 1987 ASC
conference in Urbana-Champaign, Illinois
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"the ability to cure all temporary truth of eternal triteness"-Herbert Brun
source: GWU
Block I, Unit 1 Cybernetics
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cybernetics attempts to find the common elements in the
functioning of automatic machines and of the human nervous
system, and to develop a theory that will cover the entire field
of control and communication in machines and in living
organisms.
Block I, Unit 1 Symbolic AI
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The goal is to construct machines that have the
following features:
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Use of language
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Forming and using concepts
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Complex problem-solving, such as playing
chess
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Learning
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Creativity
Block I, Unit 1 Symbolic AI
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Intelligent machines:
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Search: capable to locate the answer to a problem by
sifting all possible answers and select the correct (or the
best) one
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Symbols and rules: can manipulate words (symbols)
according to logical and linguistic rules
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Mathematical structure: the implemented model must be
a logical or mathematical structure of some kind.
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Randomness: injection some degree of randomness into
the orderly processes
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Neuron Networks: simulating the structure found in the
human brain
Block I, Unit 1 Symbolic AI
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Intelligent machines, two important keys:
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Representation: intelligent computer systems contain a
model in some logical or mathematical form, of the
problem being solved. These models are thus essentially
symbolic, consisting of logical expressions
Search: computer systems can find “intelligent” answers
to complex problems by searching among all possible
answers for the best one. The process of search will be
governed by rules.
Block I, Unit 1 Intelligence
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What is Intelligence ?
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The ability to comprehend, to understand and to profit
from experience
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A general mental capability that involves the ability to
reason, plan, solve problems, think abstractly, comprehend
ideas and language and learn
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The ability of an individual to understand and cope with
the environment
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The capacity to create constructively for the purpose of
evolutionary gain
Block I, Unit 1 Intelligence
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Observations
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Observation 1 : There is an obvious lack of agreement on
what intelligence is, and thus of the exact goals of
artificial intelligence.
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Observation 2 : The only really clear and effective
definitions of intelligence are in terms of a few examples
of intelligent behavior: perception, reasoning and action,
in the case of Winston above; decision making, problem
solving and learning in Bellman’s definition.
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Observation 3 : The overwhelming focus is on human
intelligence.
Block I, Turing work
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Alain Turing (1912, 1954) the father of AI
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Code breaker during the second world war
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Turing machine (invented on paper, 1936), it consists of:
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a read/write head (or 'scanner') with a paper tape passing
through it
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The tape is divided into squares, each square bearing a
single symbol
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This tape is the machine's general purpose storage
medium, serving both as the vehicle for input and output
and as a working memory for storing the results of
intermediate steps of the computation.
Block I, Turing work
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The machine can:
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read (i.e. identify) the symbol currently under the head
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write a symbol on the square currently under the head
(after first deleting the symbol already written there, if
any)
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move the tape left one square
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move the tape right one square
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change state
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halt.
Turing test
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Block I, Unit 1 Cybernetics Vs.
Symbolic AI
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Weak AI: computer value is that it gives us a very
powerful tool.
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Strong AI: computer is not only a tool, rather, the
appropriately programmed computer really is a mind
Block I, Unit 1 Computers
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The digital computers
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Formal systems:
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Taken
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States/starting state
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Rules
Automatic formal system: one that works by itself
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Deterministic
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Non deterministic
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Heuristics: experience based techniques for problem
solving
Block I, Unit 1 Computers
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What computers can do?
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Models, for a natural system we have:
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Simulation: is a model that captures the functional
connections between inputs and outputs of the system
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Replication: is a model that captures the functional
connections between inputs and outputs of the system and
is based on processes that are same as, or similar to, those
of the real-world-system
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Emulation: is a model that captures the functional
connections between inputs and outputs of the system and
is based on processes that are same as, or similar to, those
of the real-world-system and in the same materials as the
natural system.
Block I, Unit 1 Computers
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Optimization problems:
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Traveling Salesman Problem (TSP):
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For 5 cities, 120 possible combinations
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For 10 cities, 3.628.800 combinations
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For 15 cities, 1.307.674.368.000 combinations
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For 20 cities, 2.43  1018
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Combinatorial explosion
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TSP is an NP hard problem. (there is no known algorithm
for solving it in any realistic period of time, although such
algorithm may exist)