Artificial Life
Kiran Lakkaraju
Outline
I,What is A-Life
II,The early beginnings of A-Life.
III,Cellular Automata
IV,Current Focus
GA?s,Evolutionary Programming,
Emergent Programming.
V,Differences between AI & AL
What is Artificial Life
,collection of methods for building discrete event
simulations with evolving multiple agents”
study of the dynamics of living systems,regardless of
substrate
– Biology – Study of CARBON-based life.
Artificial life (A-Life) uses informational concepts and
computer modeling to study life in general,and terrestrial
life in particular,(Freeman quoting Langton)
,form of mathematical biology”
Life is a tale told by an idiot,full of sound and fury,signifying nothing.
W,Shakespeare
A Definition…
Artificial Life,as defined by Chris Langton,one of its
founders,is a field of study devoted to understanding life
by attempting to abstract the fundamental dynamical
principles underlying biological phenomena,and
recreating these dynamics in other physical media,such as
computers,making them accessible to new kinds of
experimental manipulation and testing
Life is a foreign language; all men mispronounce it.
Christopher Morley (1890 - 1957)
A Philosophy
Abstraction
"There's nothing implicit about the material of anything - if
you can capture its logical organisation in some other
medium you can have that same 'machine',because it's the
organisation that constitutes the machine,not the stuff it's
made of..." - Chris Langton
Look at principles of life without reference
to the implementation.
Methodology
Alife – synthetic,It tries to achieve
complexity from the combination of simpler
structures
Biology – analytic,Breakdown of Complex
phenomena to basic components
"We are no longer the knights who say 'Ni.' We are now the knights who
say 'Ikki Ikki Ikki Ikki,P'tang Zoopdah blohlfdsjfdslkjn,(Ni!)"
-Monty Python's The Quest for the Holy Grail"
History
As with most things in AI,the early results
were with Turing and Von Neumann
Theoretical Accounts of Self-Organization
Turing
Univeral Turing Machine
Can a human be represented as a Turing
Machine?
John Von Neumann
Abstract requirements for Self-Replication
Universal Constructor – using CA?s
– Interpreted code and Uninterpreted data
Copy Errors?Evolution!
Self-reliance is the only road to true freedom,and being one's own person is its ultimate reward.
Patricia Sampson
Goals
Turing?s Universal Automata
Von Neumann,Universal self-reproductive
automaton.
Logical – Not Physical.
Never became functional – too complex
Codd 1968 successful,but still very complex.
Langton succeeded 1986 – restarted the field.
Cellular Automata
Formal Definition:,A cellular automaton is a lattice of
sites,each of which can take on k values,Each site of the
automaton is updated at discrete time-steps by a finite state
automaton residing at each site and assigned a value
depending on the value of the sites around it.” (Adami
1998)
),,( )( 1)()( 1)1( titititi aaaa
If something is so complicated that you can't explain it in 10 seconds,
then it's probably not worth knowing anyway,
Calvin & Hobbes
A rule:
Informal Definition
We have a n-Dimensional array where at each time step,
the value of a certain entry depends upon the values of its
neighbors in the previous time step,
Example
Dimensionality,1D
States,_ and 1
Neighborhood,r=1,look at two neighbors
to the left and right of you?N C N
Time 0,_ _ _ _ _ _ _ _ _ _ 1 _ _ _ _ _ _ _ _ _ _
Time 1,_ _ _ _ _ _ _ _ _ 1 1 1 _ _ _ _ _ _ _ _ _
Time 2,_ _ _ _ _ _ _ _ 1 _ _ _ 1 _ _ _ _ _ _ _ _
Time 3,_ _ _ _ _ _ _ 1 1 1 _ 1 1 1 _ _ _ _ _ _ _
Time 4,_ _ _ _ _ _ 1 _ _ _ 1 _ _ _ 1 _ _ _ _ _ _
Time 5,_ _ _ _ _ 1 1 1 _ 1 1 1 _ 1 1 1 _ _ _ _ _
Time 6,_ _ _ _ 1 _ _ _ 1 _ _ _ 1 _ _ _ 1 _ _ _ _
_ _ _ -> _ 1 _ _ -> 1
_ _ 1 -> 1 1 _ 1 -> 1
_ 1 _ -> 1 1 1 _ -> _
_ 1 1 -> _ 1 1 1 -> _
1D CA Examples
Copyright David G,Green 1993.
Conway?s Game of Life
2D CA.
2 state,9-neighbor
Rules:
– A living cell (state,1”) with 2 or 3 neighbors remains
alive
– A dead cell (state,0”) with exactly 3 neighbors is born
– All other cells die (from loneliness or overcrowding),or
else remain dead.
Conway?s Game of Life cont.
Why do I get the feeling that someday I'll be describing this to a psychiatrist? The Simpsons
Von Neumann,Langton
Von Neumann able to construct a highly complex CA entity
– 29 States
– > 150,000 cells
– Self-Replication
Langton (1986) restarted the field by constructing a simple one.
Why important?
– Self Replication important
– Evolution
– Life logically implemented
CA Animation
Main Tenet
Self-Organization
– Spontaneous emergence and maintenance,of
order
– Autonomous,intrinsic development.
– Higher-level properties resulting from
interactions between simpler properties.
Turing Again.
,The chemical basis of morphogenesis”
(1952)
Showed how interacting chemical diffusion
gradients could produce higher-level
structures from initially homogeneous tissue
(MITECS,Artificial Life)
Application
Simple rules?complex behavior model
used in many simulations:
– Flocking
– Electric Power Grid
– Model Traders in the Commodity market.
– CA implementation of partial differential
equations
– CA model for freeway traffic.
Aah! Hey,get off my sugar,Bad bees! Bad! Ow,Oww! Oh,they're defending themselves somehow!
Homer Simpson
Evolution
Follows the general principles of Evolution,
Have populations of partial solutions that
are selectively recombined and mutated in
the hopes of creating a better solution,
Genetic Algorithms,Evolutionary
Programming
,… Let no one suppose that evolution will ever exempt us from
struggles,'You forget,' said the Devil,with a chuckle,'that I have
been evolving too.?”
William Ralph Inge
Applications
Genetic Programming – Koza
– Population of Programs
– Apply the evolutionary operators (crossover,
mutation) to the program
– Create better programs through this process.
Simulations
CoreWorld
Tierra – Programs that can self-replicate
existing in a simulated world with limited
resources
– Parasites,hyper-parasites
avida,amoeba
AI vs,AL
1,Complex human
functions
2,Top-down
3,Global Control
4,Complex Rules
5,Preprogrammed
behavior
6,Knowledge-
Representation
1,Basic natural
behavior
2,Bottom-up
3,Local Control
4,Simple Rules
5,Emergent behavior
6,Avoid Knowledge-
Representation &
Planning
I used to be with 'it',but then they changed what 'it' was,Now what I'm
with isn't 'it' anymore and what's 'it' seems weird and scary,
Abraham Simpson
References
Explorations in Artificial Life (special issue of AI Expert),pgs,4-8,September,
1995,Millef Freeman,An Introduction to Artificial Life
MIT Encyclopedia of Cognitive Sciences,Artificial Life,M.A,Boden.
Introduction to Artificial Life,Christopher Adami,pgs,27-28,Springer-
Verlag,New York.
,Introduction & overview of?Artificial Life?- Evolving intelligent agents for
modeling & simulation” A,Martin Wildberger,Proceedings of the 1996
Winter Simulation Conference (ACM)
Artificial Life,The Quest for a New Creation,Steven Levy,1992 Pantheon
Books.
Kiran Lakkaraju
Outline
I,What is A-Life
II,The early beginnings of A-Life.
III,Cellular Automata
IV,Current Focus
GA?s,Evolutionary Programming,
Emergent Programming.
V,Differences between AI & AL
What is Artificial Life
,collection of methods for building discrete event
simulations with evolving multiple agents”
study of the dynamics of living systems,regardless of
substrate
– Biology – Study of CARBON-based life.
Artificial life (A-Life) uses informational concepts and
computer modeling to study life in general,and terrestrial
life in particular,(Freeman quoting Langton)
,form of mathematical biology”
Life is a tale told by an idiot,full of sound and fury,signifying nothing.
W,Shakespeare
A Definition…
Artificial Life,as defined by Chris Langton,one of its
founders,is a field of study devoted to understanding life
by attempting to abstract the fundamental dynamical
principles underlying biological phenomena,and
recreating these dynamics in other physical media,such as
computers,making them accessible to new kinds of
experimental manipulation and testing
Life is a foreign language; all men mispronounce it.
Christopher Morley (1890 - 1957)
A Philosophy
Abstraction
"There's nothing implicit about the material of anything - if
you can capture its logical organisation in some other
medium you can have that same 'machine',because it's the
organisation that constitutes the machine,not the stuff it's
made of..." - Chris Langton
Look at principles of life without reference
to the implementation.
Methodology
Alife – synthetic,It tries to achieve
complexity from the combination of simpler
structures
Biology – analytic,Breakdown of Complex
phenomena to basic components
"We are no longer the knights who say 'Ni.' We are now the knights who
say 'Ikki Ikki Ikki Ikki,P'tang Zoopdah blohlfdsjfdslkjn,(Ni!)"
-Monty Python's The Quest for the Holy Grail"
History
As with most things in AI,the early results
were with Turing and Von Neumann
Theoretical Accounts of Self-Organization
Turing
Univeral Turing Machine
Can a human be represented as a Turing
Machine?
John Von Neumann
Abstract requirements for Self-Replication
Universal Constructor – using CA?s
– Interpreted code and Uninterpreted data
Copy Errors?Evolution!
Self-reliance is the only road to true freedom,and being one's own person is its ultimate reward.
Patricia Sampson
Goals
Turing?s Universal Automata
Von Neumann,Universal self-reproductive
automaton.
Logical – Not Physical.
Never became functional – too complex
Codd 1968 successful,but still very complex.
Langton succeeded 1986 – restarted the field.
Cellular Automata
Formal Definition:,A cellular automaton is a lattice of
sites,each of which can take on k values,Each site of the
automaton is updated at discrete time-steps by a finite state
automaton residing at each site and assigned a value
depending on the value of the sites around it.” (Adami
1998)
),,( )( 1)()( 1)1( titititi aaaa
If something is so complicated that you can't explain it in 10 seconds,
then it's probably not worth knowing anyway,
Calvin & Hobbes
A rule:
Informal Definition
We have a n-Dimensional array where at each time step,
the value of a certain entry depends upon the values of its
neighbors in the previous time step,
Example
Dimensionality,1D
States,_ and 1
Neighborhood,r=1,look at two neighbors
to the left and right of you?N C N
Time 0,_ _ _ _ _ _ _ _ _ _ 1 _ _ _ _ _ _ _ _ _ _
Time 1,_ _ _ _ _ _ _ _ _ 1 1 1 _ _ _ _ _ _ _ _ _
Time 2,_ _ _ _ _ _ _ _ 1 _ _ _ 1 _ _ _ _ _ _ _ _
Time 3,_ _ _ _ _ _ _ 1 1 1 _ 1 1 1 _ _ _ _ _ _ _
Time 4,_ _ _ _ _ _ 1 _ _ _ 1 _ _ _ 1 _ _ _ _ _ _
Time 5,_ _ _ _ _ 1 1 1 _ 1 1 1 _ 1 1 1 _ _ _ _ _
Time 6,_ _ _ _ 1 _ _ _ 1 _ _ _ 1 _ _ _ 1 _ _ _ _
_ _ _ -> _ 1 _ _ -> 1
_ _ 1 -> 1 1 _ 1 -> 1
_ 1 _ -> 1 1 1 _ -> _
_ 1 1 -> _ 1 1 1 -> _
1D CA Examples
Copyright David G,Green 1993.
Conway?s Game of Life
2D CA.
2 state,9-neighbor
Rules:
– A living cell (state,1”) with 2 or 3 neighbors remains
alive
– A dead cell (state,0”) with exactly 3 neighbors is born
– All other cells die (from loneliness or overcrowding),or
else remain dead.
Conway?s Game of Life cont.
Why do I get the feeling that someday I'll be describing this to a psychiatrist? The Simpsons
Von Neumann,Langton
Von Neumann able to construct a highly complex CA entity
– 29 States
– > 150,000 cells
– Self-Replication
Langton (1986) restarted the field by constructing a simple one.
Why important?
– Self Replication important
– Evolution
– Life logically implemented
CA Animation
Main Tenet
Self-Organization
– Spontaneous emergence and maintenance,of
order
– Autonomous,intrinsic development.
– Higher-level properties resulting from
interactions between simpler properties.
Turing Again.
,The chemical basis of morphogenesis”
(1952)
Showed how interacting chemical diffusion
gradients could produce higher-level
structures from initially homogeneous tissue
(MITECS,Artificial Life)
Application
Simple rules?complex behavior model
used in many simulations:
– Flocking
– Electric Power Grid
– Model Traders in the Commodity market.
– CA implementation of partial differential
equations
– CA model for freeway traffic.
Aah! Hey,get off my sugar,Bad bees! Bad! Ow,Oww! Oh,they're defending themselves somehow!
Homer Simpson
Evolution
Follows the general principles of Evolution,
Have populations of partial solutions that
are selectively recombined and mutated in
the hopes of creating a better solution,
Genetic Algorithms,Evolutionary
Programming
,… Let no one suppose that evolution will ever exempt us from
struggles,'You forget,' said the Devil,with a chuckle,'that I have
been evolving too.?”
William Ralph Inge
Applications
Genetic Programming – Koza
– Population of Programs
– Apply the evolutionary operators (crossover,
mutation) to the program
– Create better programs through this process.
Simulations
CoreWorld
Tierra – Programs that can self-replicate
existing in a simulated world with limited
resources
– Parasites,hyper-parasites
avida,amoeba
AI vs,AL
1,Complex human
functions
2,Top-down
3,Global Control
4,Complex Rules
5,Preprogrammed
behavior
6,Knowledge-
Representation
1,Basic natural
behavior
2,Bottom-up
3,Local Control
4,Simple Rules
5,Emergent behavior
6,Avoid Knowledge-
Representation &
Planning
I used to be with 'it',but then they changed what 'it' was,Now what I'm
with isn't 'it' anymore and what's 'it' seems weird and scary,
Abraham Simpson
References
Explorations in Artificial Life (special issue of AI Expert),pgs,4-8,September,
1995,Millef Freeman,An Introduction to Artificial Life
MIT Encyclopedia of Cognitive Sciences,Artificial Life,M.A,Boden.
Introduction to Artificial Life,Christopher Adami,pgs,27-28,Springer-
Verlag,New York.
,Introduction & overview of?Artificial Life?- Evolving intelligent agents for
modeling & simulation” A,Martin Wildberger,Proceedings of the 1996
Winter Simulation Conference (ACM)
Artificial Life,The Quest for a New Creation,Steven Levy,1992 Pantheon
Books.
