What is AI…? - Department of Computing
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Transcript What is AI…? - Department of Computing
What is AI…?
Dr. Simon Colton
Computational Bioinformatics Laboratory
Department of Computing
Imperial College, London
What isn’t Artificial Intelligence
AI in PopSci books and the Media
Kevin “March of the Machines” Warwick
– Robots will take over the Earth
Roger “Emperors New Mind” Penrose
– Computers will never be intelligent
What isn’t AI
Mark “The Human Computer” Jeffery
– Computers will evolve to be human
?
Ray “The Age of Spiritual Machines” Kurzweil
– Humans will evolve to be computers
Two Restricted Views of AI
As a tool to study (human) intelligence
– Just the latest part of the philosophers toolbox
– Mostly scientific
As a set of methods for solving problems
– Which take intelligence to solve in humans
– Mostly technological
In reality, AI encompasses both of these
– Part science, part technology
Two Characterisations of AI
“What problem
do I have?”
“How on earth can I get
my machine to do
clever things?”
Characterisation by Problem
If you know the type of problem
– There are established techniques to use
Some problems you may want solving:
– Translating, proving, learning, optimising, …
– Seeing, hearing, speaking, moving, …
This is how AI is usually taught
– And how subjects are arranged in textbooks
Considerations for Problem Solving
How to specify the problem
– So the computer knows when it’s done
How to represent solutions
– Representation, representation, representation
– Symbolic and non-symbolic
How to search for solutions
– Calculation, simple search, rules of thumb
An Example: Computer Maths
Would you do this by hand if you had a
calculator: 171717 * 98765?
– If we can get a computer to do it,
• Then it’s extremely reliable
Computers do more complicated maths:
e.g., 17 < x < 19, 15 < x+y < 20, 13 < y-x < 17
And can beat humans sometimes:
– I wanted to prove, that, in ring theory:
• (all x, (x+x = x*x)) (all w x (((w*w)*x)*(w*w)) = id)
– I couldn’t prove this, but Otter could!
A Nicer Characterisation
As answers to:
– “How can I get my machine to be clever”
Seven answers over the years:
–
–
–
–
–
–
–
Use logic
Use introspection
Use brains
Use evolution
Use the physical world
Use society
Use ridiculously fast computers
Elementary, my dear Watson
Logical approach
– Idea: represent and reason
“It’s how we wish we solved
problems…
– Just like Sherlock”
Very well respected
– Established
• 3000 years of development
– Techniques for reasoning
• Deduction & induction
– Programming languages
Introspection
Logic has limits
– Combinatorial explosion
“Maybe we’re not logical
– But we are intelligent”
Use introspection
– Can be highly effective
– Can be problematic
Heuristic search
– Using rules of thumb to
guide the solving process
BrainWare
“Maybe we don’t know our
psychology
– But it’s our brains which do
the intelligent stuff”
And we do know
– Some neuroscience
Idea is to build:
– Artificial Neural Networks
– Simulate neurons firing
• Networks configuring themselves
Mostly used for prediction
– E.g., stock markets (badly)
Evolve or Perish
“Our brains give us our smarts,
– But what gave us our brains?”
Idea: evolve programs
– Simulate reproduction and
survival of fittest
Problem Solving:
– Genetic algorithms (parameters)
– Genetic programming (program)
Artificial Life
– Can we evolve “living” things
The More the Merrier
“We live and work in societies
– Each of us has a job to do”
Idea to simulate society
– Autonomous agents
Each has a subtask
– Together solve the problem
Agencies have structure
Agents can
– compete, co-operate, haggle,
argue, …
The Harsh Realities of Life
“But we evolved intelligence
for a reason”
Idea: get robots to do simple
things in the physical world
– Dynamic & dangerous
From survival abilities
– Intelligence will evolve
Standing up is much more
intelligent than
– Translating French to German
– In Evolutionary terms
Brute Force
“Let’s stop being so
clever and use
computers to their full”
– Processor/memory gains
have been enormous
Can solve problems in
“stupid” ways
– Relying on brute force
The Deep Blue way
– Little harsh on IBM
An Example: RHINO
Robotic museum tour guide
– Robot + computers
– And worried researchers
• Who didn’t intervene
Highly successful
– 18.6 kilometres, 47 hours
– 50% attendance rise
– 1 tiny mistake
• No breakage/injury
Great science
– Using many approaches
– Won best paper award
Where is AI?
In industry – see Rob’s talk
In education – see Andrew’s talk
In research
– Computing, psychology, philosophy,
– Cognitive science, linguistics, biology,
– Mathematics, physics, …
Artificial Intelligence does not class
itself as simply a subset of computing
Some Aspirations
“Big” AI
– Building of human-level intelligence
into robots like Lieutenant Commander Data
“Small” AI
– Get computers to undertake some intelligent tasks
– Mostly problem solving
– But sometime more creative “artefact generation”
• Painting pictures, composing melodies, writing poems, …
– This is what most of us do
Computers can Create
Produced by the NeVar system © Machedo
Uses Genetic Programming
Evolve the program to draw these
Evolutionary
Art is very big
Resources…
This is meant to stimulate questions