But Chris Langton doesn't find the prospect of artificial life
creating its own civilization so goofy. Langton has gotten a lot of
press for being the maverick who launched the fashionable field of
artificial life. He has a good story, worth retelling very briefly
because his own journey recapitulates the awakening of human-made,
Several years ago Langton and I attended a week-long science conference
in Tucson, and to clear our heads, we played hooky for an afternoon. I
had an invitation to visit the unfinished Biosphere 2 project an hour
away, and so as we cruised the black ribbon of asphalt that winds
through the basins of southern Arizona, Langton told me his life story.
At the time, Langton worked at the Los Alamos National Laboratory as a
computer scientist. The entire town and lab of Los Alamos were
originally built to invent the ultimate weapon. So I was surprised to
hear Langton begin his story by saying he was a conscientious objector
during the Vietnam War.
As a CO, Langton scored a chance to do alternative service as a hospital
orderly at Boston's Massachusetts General Hospital. He was assigned the
undesirable chore of transporting corpses from the hospital basement to
the morgue basement. On the first week of the job, Langton and his
partner loaded a corpse onto a gurney and pushed it through the dank,
underground corridor connecting the two buildings. They needed to push
it over a small concrete bridge under the only light in the tunnel, and
as the gurney hit the bump, the corpse belched, sat upright, and started
to slide off its perch! Chris spun around to grab his partner, but he
saw only the distant doors flapping behind his coworker. Dead things
could behave as if they were alive! Life was behavior; that was the
Langton told his boss he couldn't go back to that job. Could he do
something else? "Can you program computers?" he was asked. "Sure."
He got a job programming early-model computers. Sometimes he would let a
silly game run on the unused computers at night. The game was called
Life, devised by John Conway, and written for the mainframe by an early
hacker named Bill Gosper. The game was a very simple code that would
generate an infinite variety of forms, in patterns reminiscent of
biological cells growing, replicating, and propagating on an agar plate.
Langton remembered working alone late one night and suddenly feeling the
presence of someone, something alive in the room, staring at him. He
looked up and on the screen of Life he saw an amazing pattern of
self-replicating cells. A few minutes later he felt the presence again.
He looked up again and saw that the pattern had died. He suddenly felt
that the pattern had been alive -- alive and as real as mold on an agar
plate -- but on a computer screen instead. The bombastic idea that perhaps
a computer program could capture life sprouted in Langton's mind.
He started fooling around with the game, probing it, wondering if it was
possible to design a game like Life that would be open ended -- so that
things would start to evolve on their own. He honed his programmer
skills. On the job Langton was given the task of transferring a program
from an out-of-date mainframe computer to a very different newer one. In
order to do this, the trick was to abstract the operation of the
hardware of the old computer and put it into the software of the newer
one -- to extract the essential behavior of the hardware and cast it in
intangible symbols. This way, old programs running on the new machine
would be running in a virtual old computer emulated in software in the
new computer. Langton said, "This was a first-hand experience of moving
a process from one medium to another. The hardware didn't matter. You
could run it on any hardware. What mattered was capturing the essential
processes." It made him wonder if life could be taken from carbon and
put into silicon.
After his service stint Langton spent his summers hang-gliding. He and a
friend got a job hang-gliding over Grandfather Mountain in North
Carolina for $25 per day as an airborne tourist attraction. They stayed
aloft for hours at a time in 40-mile-per-hour winds. Swiped by a freak
gust one day, Langton crashed from the sky. He hit the ground in a fetus
position and broke 35 bones, including all the bones in his head except
his skull. Although he smashed his knees through his face, he was alive.
He spent the next six months on his back, half-conscious.
As he recovered from his massive concussions, Langton felt he was
watching his brain "reboot," just as computers that are turned off have
to rebuild their operating system when turned back on. One by one
certain deep functions of his mind reappeared. In an epiphany of sorts,
Langton remembers the moment when his sense of proprioception -- the sense
of being centered in a body -- returned. He was suddenly struck with a
"deep emotional gut feeling" of his own self becoming integrated, as if
his machine had completed its reboot and was now waiting for an
application. "I had a personal experience of what growing a mind feels
like," he told me. Just as he had seen life in a computer, he now had a
visceral appreciation of his own life being in a machine. Surely, life
must be independent of its matrix? Couldn't life in both his body and
his computer be the same?
Wouldn't it be great, he thought, if he could get something alive with
evolution going in a computer! He thought he would start with human
culture. That seemed an easier simulation to start with than simulated
cells and DNA. As a senior at the University of Arizona, Langton wrote a
paper on "The Evolution of Culture." He wanted his anthropology,
physics, and computer science professors to let him design a degree
around building a computer to run artificial evolution, but they
discouraged him. On his own he bought an Apple II and wrote his first
artificial world. He couldn't get self-reproduction or natural
selection, but he did discover the literature of cellular automata -- of
which the Game of Life, it turned out, was only one example.
And he came across John von Neumann's proofs of artificial
self-replication from the 1940s. Von Neumann had come up with a landmark
formula that would self-replicate. But the program was unwieldy,
inelegantly large and clumsy. Langton spent months of long nights coding
his Apple II (a handy advantage that von Neumann didn't have; he did his
with pencil on paper). Eventually guided only by his dream to create
life in silicon, Langton came up with the smallest self-replicating
machine then known to anyone. On the computer screen the self-replicator
looked like a small blue Q. Langton was able to pack into its loop of
only 94 symbols a complete representation of the loop, instructions on
how to reproduce, and the trick of throwing off another just like
itself. He was delirious. If he could engineer such a simple replicator,
how many of life's other essential processes could he also mimic?
Indeed, what were life's other essential processes?
A thorough search of the existing literature showed that very little
science had been written on such a simple question, and what little
there was, was scattered here and there in hundreds of tiny corners.
Emboldened by his new research position at the Los Alamos Labs, in 1987
Langton staked his career on gathering an "Interdisciplinary Workshop on
the Synthesis and Simulation of Living Systems," -- the first conference on
what Langton was now calling Artificial Life. In his search for any and
all systems that exhibit the behavior of living systems, Langton opened
the workshop to chemists, biologists, computer scientists,
mathematicians, material scientists, philosophers, roboticists, and
computer animators. I was one of the few journalists attending.