;)
ome images on
the back jacket of Stephen Wolfram's 1,197-page tome, "A New Kind of
Science," are familiar: a splash of liquid, jets of gas, sea anemone,
ancient mosaics and mollusk shells. But others become understandable
only after working through ideas in this much-awaited book: spindly
sketches of leaves and snowflakes, a baroque lacework of light,
schematic diagrams that waver under the gaze.
Many of these images, created by Mr. Wolfram, are ghostlike
reductions of familiar objects, skeletal representations of processes
that may lie beneath natural forms. And they were produced during a
decade of work that was kept hidden from professional scrutiny.
Now Mr. Wolfram is finally publishing his work, and his claims
surpass the most extravagant speculation. He has, he argues, discovered
underlying principles that affect the development of everything from the
human brain to the workings of the universe, requiring a revolutionary
rethinking of physics, mathematics, biology and other sciences. He
believes he has shown how the most complex processes in nature can arise
out of elemental rules, how a wealth of diverse phenomena - the infinite
variety of snowflakes and the patterns on sea shells - are generated
from seemingly trivial origins.
Conducting experiments on a computer, where he says he has logged 100
million keystrokes in the last 10 years, Mr. Wolfram wrote simple
programs that generated odd and intricate patterns to test his ideas
about complexity. He then tried to imitate designs found in nature. He
argues that natural phenomena can be explored as if they were, in fact,
computer programs, their evolution and behavior the products of
intricate calculations.
"I have discovered vastly more than I ever thought possible," Mr.
Wolfram writes in the book's preface, "and in fact what I have done now
touches almost every existing area of science, and quite a bit besides."
These might seem the claims of a semimystical scientific crank. After
all, the book is being published (on Tuesday) not by a university press
but by Mr. Wolfram's own company (Wolfram Media Inc.), and he has
insisted on secrecy in a scientific world used to peer review and public
conferences. But secrecy and grandiosity have also accompanied major
scientific works .
Terrence Sejnowski, who directs the Computational Neurobiology
Laboratory at the Salk Institute for Biological Studies in La Jolla,
Calif., has found Mr. Wolfram's work useful for designing computer
simulations of nerve cells and synapses. He has called Mr. Wolfram "the
smartest scientist on the planet."
Mr. Wolfram, who was born in Britain, published his first paper on
particle physics in 1975 at age 15, and obtained a doctorate at Caltech
at 20 (where Richard Feynman called him "astonishing"). He won a
MacArthur Foundation Fellowship at 21, reshaped the ways in which
complex phenomena (like the movements of fluids) were analyzed before he
was 26, founded an institute for the study of complexity at the
University of Illinois, and then left academic life and research
science, starting a software company, Wolfram Research Inc., in 1987.
His main commercial product, a program called Mathematica, has become an
international standard, used as a mathematical tool by over a million
scientists and students and engineers in areas ranging from medical
research to the analysis of weather.
Mr. Wolfram freely confesses to a high opinion of his
accomplishments. In a recent interview, he explained that if he were
more modest he would be less clear and less successful. "Ultimately," he
said of his book, "confidence is necessary in order to undertake a
project of this size." Its goal is to change the very direction of
scientific research. He ranks one of his discoveries about complexity
among the most important "in the whole history of theoretical science."
But because Mr. Wolfram has been so secretive, he has shown his work
only to a small circle of selected colleagues. Gregory J. Chaitin, a
mathematician at IBM Watson Research
Center in Yorktown Heights, N.Y., for example, who has read the book,
said in an interview that he was convinced of its importance but
anticipated controversy: "Stephen has gone out on a limb. He is
proposing a paradigm shift. A new twist on everything." It will take
months, even years, before all the thorough, independent professional
assessments are in, which should not be surprising given Mr. Wolfram's
undertaking.
He really is proposing, as the book's title puts it, a "new kind of
science." He wants to displace the projects and theories and priorities
that now characterize academic science. And he refuses to be limited by
disciplinary boundaries or by the assertions of experts in other fields.
"No doubt," he writes, "this book will draw the ire" of some of them. "I
think I was a somewhat brash teenage scientist," Mr. Wolfram said,
adding that he still seems to affect people the same way.
As a colleague once put it, Mr. Wolfram has "stepped on a lot of
toes." Tensions arose in many institutional settings before he set out
on his own. In the early 1980's, there was even a court battle with
Caltech over ownership of computer software designed by Mr. Wolfram. In
addition, Mr. Wolfram noted, when he began his work on complexity he
confidently expected others to follow through on his suggestions;
instead, he bluntly said, without his leadership the field did
"horribly, horribly." Such frustrations, he explained, eventually
convinced him to design an alternative scientific career, founding his
own company and pursuing his interests without any need for grants or
support.
This independence is even reflected in the book's style. It requires,
Mr. Wolfram writes, "no specialized scientific or other knowledge to
follow." Mathematical formulas are eliminated; illustrations
predominate; professional prose is avoided.
His theory developed out of a series of elementary computer
experiments he conducted in the early 1980's. He was examining the way
simple computer programs can generate shaded patterns on grids composed
of square cells. A computer would be given a row of cells, some black,
some white, along with a set of simple rules that determine how
succeeding lines of shaded cells are to be generated. Such programs have
been called "cellular automata."
As one might expect, simple rules generally yield simple patterns.
But Mr. Wolfram found one rule for generating a cellular automaton that
yields no clear pattern at all. Its appearance is bizarre,
unpredictable, seemingly chaotic. No one, Mr. Wolfram writes, could have
expected this. Complexity was thought to arise only out of very complex
rules; here it is generated out of simplicity.
Such cellular automata are at the heart of this book, for Mr. Wolfram
argues that many complex processes - the movements of a fluid, the
shapes of leaves, the patterns on a mollusk shell - can, in fact, be
modeled by simple programs like cellular automata. Such elementary
programs, he suggests, can even be used to explain the nature of space
and time or outline the vagaries of visual perception. Existing
mathematics and physics, Mr. Wolfram argues, are inadequate to the
task.
Here is where matters get quite difficult very fast. Not only can
complex designs and processes arise out of the simplest of rules, but,
Mr. Wolfram asserts, simple rules actually lie behind the most
sophisticated processes in the universe. Indeed, the universe itself, he
argues, is generated by such rules. He presents an example of one
cellular automaton program that produces such sophisticated patterns
that it can act like a powerful computer. The details are highly
technical, but this automaton can actually replicate other processes and
patterns just as a computer can be turned into a word-processor one
minute and a game machine the next. It has what are called "universal"
properties.
Hypothetically, the movement of cigarette smoke in the air could be
mirrored by such a seemingly simple cellular automaton; so could the
processes of the human brain. In fact, such powerful "computers," Mr.
Wolfram says, are far more plentiful, even in the natural world, than
has ever been thought. Moreover, he argues that all universal computing
systems are equivalent; no calculating machine can be more powerful, no
computer more sophisticated than the cellular automaton Mr. Wolfram
describes. This insight alone, he claims, "has vastly richer
implications" than "any single collection of laws in science."
And indeed, this principle, as asserted by Mr. Wolfram, leads to a
startling conclusion. Scientists are accustomed to analyzing some
systems by discovering abstract principles that can describe their
behavior. Kepler's laws, for example, can predict and describe the
motion of the planets. But some extraordinarily complex processes -
like, perhaps, the curl of cigarette smoke - cannot be encompassed by
such a law; for that law would require one "universal" computational
system to be more powerful than another.
So all we can do in such cases is discover the simple rules that give
birth to the complexity, the rules that act like the striking of the
match before smoke begins to rise. Everything else - the position and
density of smoke at a particular time and under certain conditions - can
be found only by "experiment": the process must run its course. There
are limits to the powers of science to generalize and predict.
Mr. Wolfram spins out elaborate speculations based on these ideas -
suggestions about free will, the structure of space, the nature of
mathematics. "There is so much in the book," Mr. Sejnowski said, "that
it will be years, literally years, before people assimilate it."
Meanwhile, reactions to Mr. Wolfram, he believes, will be "all over the
map."
Mr. Wolfram is sanguine: "I am quite certain this is going to work. I
have never deluded myself before."
