2. Table of Contents

There are currently three parts to this FAQ:

        1. Introductions & General Questions [ under construction ]
        2. Artificial Life Resources - Net & Other [ under construction ]
        3. Glossary of Terms [ just not started yet ]

In addition, the FAQs of the following newsgroups contain quite a bit of
relevant information:

        comp.ai.genetic
        comp.theory.cell-automata
        alt.memetics

These are available on the FTP server rtfm.mit.edu, as well as many other
FTP servers.  Contact brown@krl.caltech.edu for more details, or go to
those newsgroups.

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Part 1: Introductions and General Questions

Q1: What is Artificial Life, and where is some introductory material?
Q2: What is the purpose and charter of comp.ai.alife?
Q3: How do I find a particular AL program/demo?
Q4: How are Artificial Life and Artificial Intelligence related?

------------------------------

Q1: What is Artificial Life, and where is some introductory material?

What is Artificial Life?
------------------------

Biology is the scientific study of life - in principle, anyway. In
practice, biology is the scientific study of life on Earth based on
carbon-chain chemistry. There is nothing in its charter that restricts
biology to carbon-based life; it is simply that this is the only kind
of life that has been available to study. Thus, theoretical biology
has long faced the fundamental obstacle that it is impossible to
derive general principles from single examples.

Without other examples, it is difficult to distinguish essential
properties of life - properties that would be shared by any living
system - from properties that may be incidental to life in principle,
but which happen to be universal to life on Earth due solely to a
combination of local historical accident and common genetic descent.

In order to derive general theories about life, we need an ensemble
of instances to generalize over. Since it is quite unlikely that alien
lifeforms will present themselves to us for study in the near future,
our only option is to try to create alternative life-forms ourselves -
Artificial Life - literally ``life made by Man rather than by
Nature.''

Artificial Life (``AL'' or ``Alife'') is the name given to a new
discipline that studies "natural" life by attempting to recreate
biological phenomena from scratch within computers and other
"artificial" media. Alife complements the traditional analytic
approach of traditional biology with a synthetic approach in which,
rather than studying biological phenomena by taking apart living
organisms to see how they work, one attempts to put together systems
that behave like living organisms.

The process of synthesis has been an extremely important tool in many
disciplines.  Synthetic chemistry - the ability to put together new
chemical compounds not found in nature - has not only contributed
enormously to our theoretical understanding of chemical phenomena, but
has also allowed us to fabricate new materials and chemicals that are
of great practical use for industry and technology.

Artificial life amounts to the practice of ``synthetic biology'' and,
by analogy with synthetic chemistry, the attempt to recreate
biological phenomena in alternative media will result in not only
better theoretical understanding of the phenomena under study, but
also in practical applications of biological principles in the
technology of computer hardware and software, mobile robots,
spacecraft, medicine, nanotechnology, industrial fabrication and
assembly, and other vital engineering projects.

By extending the horizons of empirical research in biology beyond the
territory currently circumscribed by life-as-we-know-it, the study of
Artificial Life gives us access to the domain of life-as-it- could-be,
and it is within this vastly larger domain that we must ground general
theories of biology and in which we will discover practical and useful
applications of biology in our engineering endeavors.

                                        -- Chris G. Langton


Where can I find some good introductory material?
-------------------------------------------------

There are several "popular science" books out there.  _Artificial Life:
the Quest for a New Creation_, by Steven Levy, was one of the first;
Levy presents a large amount of material detailing the genesis of the
field, including a description of many still-active projects.  This
would be my first recommendation for a newcomer.

There is a World-Wide-Web page for this book at the URL
http://mosaic.echonyc.com/~steven/ArtificialLife.html.

M. Mitchell Waldrop's _Complexity: The Emerging Science at the Edge of
Order and Chaos_ (ISBN 0-671-76789-5) discusses the history of complex
systems study.  In specific, it details the founding of the Santa Fe
Institute, which is actively researching most aspects of complex systems,
including Artificial Life.

Rudy Rucker's _Artificial Life Lab_ has been recommended as a good way to
get involved; I haven't yet read it.

Finally, the book _Out of Control_ by Kevin Kelly is reputed to be a good
1994 overview of technology, with an emphasis on emergent behavior and
modelling life in a computer environment.

------------------------------

Q2: What is the purpose and charter of the comp.ai.alife newsgroup?

The purpose of comp.ai.alife is to provide an unmoderated forum in which
to discuss topics related to the field of Artificial Life, as well as
providing a centralized resource base for queries regarding AL research.

* Topics for discussion in the newsgroup can include, but not be limited to:

  -- optimization techniques (such as genetic algorithms) and modelling
        algorithms
  -- the definition of a living system and "Life"
  -- self-organizing systems
  -- the origin of life
  -- evolutionary learning
  -- the development of ecosystems
  -- complex system dynamics (with specific relation to living systems)
  -- book and software reviews (non-commercial advertisements, as well)

------------------------------

Q3: How do I find a particular AL program/demo?

Apart from the list [ below ] which contains references to programs and demos
which have often been requested on the newsgroup, the best way to find
something specific is to ask on the newsgroup!  Even if the people from the
particular project don't actually read the newsgroup, someone who knows them
probably does...

How do I find...
----------------

1. Tierra

        The complete source code and documentation (NOT the executables)
for Tom Ray's tierra program are available via anonymous FTP at

        ftp://tierra.slhs.udel.edu [ 128.175.41.34 ] and
        ftp://life.slhs.udel.edu [ 128.185.41.33 ]

        in the directory /tierra, file tierra.tar.Z.

2. Karl Sim's movie (from the ALIFE IV conference)

        Karl Sim's movie, presented at the ALIFE IV conference, is available
via FTP at:

        ftp://ftp.think.com/users/karl/creatures-demo.mpg

------------------------------

Q4: How are Artificial Life and Artificial Intelligence related?

There is a connection between the two fields in both methodology and
research.  AI is much older, with conceptual work dating to 1950 and
beyond, while AL coagulated in the late 1980s, when people recognized
similarities in the work they were doing.  AI methodologies play a
large part in AL work, partly because of the recognizable similarities
in the two disciplines: AI studying intelligence, AL studying life,
both with an eye to usefulness and reproducibility. And, in recent years,
"traditional" AI researchers have focussed on AL techniques for
autonomous learning, among other things.

In spite of these similarities, there are several dissimilarities.
AL is grounded in biology, physics, chemistry and mathematics,
while AI is pursued mainly by computer scientists, engineers, and
psychologists.  Also, the general philosophy of researchers in the fields
seems to approach similar problems from different sides; AL from the
ground up, in an attempt to study synthesis, AI from the top down,
focussing on results and not implementation.

[ The text above is my opinion; I welcome alternative viewpoints on the
  subject, of course. --Titus ]

------------------------------

Before you sue my pants off for some information I've misrepresented in this
file, read the...

Legal Necessities:

       This article is provided as is without any express or implied
       warranties.  While every effort has been taken to ensure the
       accuracy of the information contained in this article, the
       author/maintainer/contributors (take your pick) assume(s) no
       responsibility for errors or omissions, or for damages resulting
       from the use of the information contained herein.

       The contents of this article reflect my opinions only and not
       necessarily those of my employer.

And, finally, copied right off of the FAQs-about-FAQs guide, by Russ Hersch:

Copyright (c) 1995 by C. Titus Brown, all rights reserved.

This FAQ may be posted to any USENET newsgroup, on-line service, or BBS
  as long as it is posted in its entirety and includes this copyright
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This FAQ may not be distributed for financial gain.
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---
--
Titus Brown, brown@krl.caltech.edu.

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