David Pines, Distinguished Professor of Physics, UC Davis
and Chief Evangelist, ICAM
When electrons or atoms or people interact, the behavior of the whole is different from that of its parts. We call that collective behavior emergent. Emergence thus refers to collective phenomena or behaviors in complex systems that do not exist in their individual parts; gateways to emergence are the regularities that characterize emergent behavior and the organizing principles that may be able to explain it.
In both science and society, developing an emergent perspective means a focus on identifying gateways to emergent system behavior. Because emerging global challenges have no unique cause, there can be no unique or even “best” response. An emergent strategy to address these therefore involves pursuing simultaneously many different partial solutions, with a focus on connections and synergies among these that can accelerate progress and lead to a whole that is greater than the sum of its parts.
We live in an emergent universe, in which the interaction between its parts, be they people or electrons, gives rise to emergent collective behaviors that are different from those of the parts separately and are generally unpredictable from knowledge only of those parts and their interaction. To understand this emergent universe, scientists are replacing the traditional reductionist approach, with its focus on using the individual components as basic building blocks, by an emergent perspective, in which the focus is on characterizing collective emergent behavior and the search for the collective organizing concepts and principles that bring it about. These gateways to emergence are the new basic building blocks we use to understand quantum matter or living matter, the cosmos, ourselves, or the societies in which we live.
In the physical and biological sciences, we carry out experiments in the laboratory and analyze observational data to discover the regularities that characterize emergent behavior, and ask whether the gateways to emergent behavior that have been identified in one area might provide us with useful insights into the origins of emergent collective behavior in another.
An emergent perspective is essential as we confront emerging global challenges—climate change, our troubled educational and infrastructure systems, terrorism, our current global economic meltdown, etc. These are all caused by humans, and in searching for an appropriate response, we properly begin by seeking to identify their origins in societal behavior.
But now there is a difference from simpler systems: those origins are many, not unique. Moreover, because feedback leading to non-linear behavior plays a significant role, origins are both difficult to identify and nearly impossible to separate. Armed with this emergent perspective, what is the right strategy?
First, keep clearly in mind that since emerging global challenges have no unique cause, that there can be no unique or even “best” solution to these. Therefore the right emergent strategy for making progress is to pursue simultaneously many different partial solutions, while searching for synergies among these. Second, experiment, experiment, experiment, monitor regularly one’s progress, and adapt, adapt, adapt one’s strategy in pursuing these. Third, do not hesitate to invent new institutions.
More details and background information
Emergence is a bulk property. When we bring together the component parts of any system, be it people in a society or matter in bulk, the behavior of the whole is very different from that of its parts, and we call the resulting behavior emergent.
From the discovery of novel ordered states in quantum matter to eggs cooking, birds flocking, collective behavior in ant colonies, the development of consciousness in infants, the latest measurements on the early universe, global climate change, or our current global economic meltdown—emergence is all around us.
More matter turns out to be not only different, but is almost always unpredictable from a knowledge of its component parts and their interactions.
We know the simple equations that govern our immediate world, but find these are almost useless in telling us about the emergent behavior we encounter, whether we are working on a problem at the frontiers of science, cooking a meal, or seeking to understand and change societal behavior. So we must conclude that the dream of some twentieth century reductionists [according to Wikipedia, reductionism can either mean (a) an approach to understand the nature of complex things by reducing them to the interactions of their parts, or to simpler or more fundamental things or (b) a philosophical position that a complex system is nothing but the sum of its parts, and that an account of it can be reduced to accounts of individual constituents]—discovering a “Theory of Everything”—is hollow.
Thus matter in bulk acquires properties that are different from those of its fundamental constituents (electrons and nuclei) and we now recognize that a knowledge of their interactions does not make it possible to predict its properties, whether one is trying to determine whether a material becomes a magnet or a novel superconductor, to say nothing of understanding the behavior of a cell in living matter or the behavior of the neurons in the human brain.
Feynman famously said: “life is nothing but the wiggling and jiggling of atoms,” but this does not tell us how these gave rise to LUCA, the last universal ancestor that is the progenitor of living matter, to say nothing of its subsequent evolution. It follows that we need to rethink the role of reductionism in understanding emergent behavior in the physical, biological, and social sciences.
An Emergent Perspective and Emergent Strategies
What replaces the reductionist dream? The short answer is an emergent perspective—a recognition that understanding emergent behavior requires a change of focus. Instead of adopting the traditional reductionist approach that begins by identifying the individual constituents (quarks, electrons, atoms, individuals) and using these as the basic building blocks for building a model of emergent behavior, focus instead on identifying the gateways to emergent behavior— the collective organizing concepts and principles that characterize and explain emergent behavior, for these are the basic building blocks one needs to understand emergence.
The chef cooking eggs has found through experiment the organizing principles at work that change their state from liquid to semi-solid—(over- easy, shirred, scrambled, omelet, soufflé, fritatta…)—and has learned that the pan, the butter, the temperature of the stove top or oven, the added ingredients, the altitude, and especially the chef—all play a role in determining the outcomes.
The physical scientist studying bulk matter seeks to identify the collective building blocks (symmetry, broken symmetry, effective fields, criticality, feedback, energy landscapes, frustration, quasiparticles, collective modes, coherent and competing states, universal, scaling, or protected behavior, etc.) that are candidate gateways to emergence in the system under investigation, and to understand their range of applicability.
For the physical scientist or the social scientist an emergent strategy involves then the following steps:
focus on the experimental results—search for regularities (patterns, possible scaling behavior, etc…) in the experimental or observational data obtained by many different probes
consult one’s catalogue of organizing concepts and decide, at a qualitative level, on candidate organizing concepts that might be responsible for the most important experimental regularities
develop a phenomenological description that incorporates these organizing principles and links the results obtained using different experimental probes
only then put on a “reductionist” hat—developing a candidate microscopic “theory” by proposing and solving a simplified “toy” model that embodies the candidate organizing principles.
Both the reductionist and the scientist with an emergent perspective focus on fundamentals. For the reductionist these are the individual constituents of the system, and the forces that couple them. For the “emergentist”—the physical scientist with an emergent perspective—the fundamentals are the collective organizing principles that bring about the emergent behavior of the system as a whole, from the second law of thermodynamics to the mechanisms producing the novel coherent states of matter that emerge as a material seeks to reduce its entropy as its temperature is lowered.
The difference between a reductionist perspective and an emergent one can also be viewed in terms of starting points and ending points. In considering a new problem that has turned up in the laboratory or is posed by observation, the reductionist focuses at the outset on solving a “standard” model that incorporates the basic interactions between the individual components of the system. The scientist with an emergent perspective puts on a reductionist hat, but does so very much later, toward the end point of research on the problem, when, through continued attention to the experimental results obtained using a broad spectrum of probes of its emergent behavior, it has been possible to identify the organizing principles that must be incorporated in a candidate model, one that is nearly always quite different from the standard model of the reductionist.
Emerging Societal Challenges
For the citizen and world leader alike, an emergent perspective is essential as we confront emerging global challenges—climate change, our failed educational system, terrorism, our current global economic meltdown, etc. These are all caused by humans, and in searching for an appropriate emergent response, we properly begin by seeking to identify their origins in societal behavior.
But now there is a difference: their origins are many, not unique. Moreover, because feedback leading to non-linear behavior plays a significant role, these origins are both difficult to identify and nearly impossible to separate. Armed with this emergent perspective, what is the right strategy?
Because emerging global challenges have no unique cause, it follows that there is no unique or even “best” solution to these.
Emergent strategies for making progress involve trying simultaneously many different partial solutions, inventing new institutions, and experiment, experiment, experiment in pursuing these.
These involve as well monitoring carefully the results of these different experimental approaches, searching for synergies, and being adaptive- modifying approaches as information becomes available on their impact.
Establishing synergies between candidate solutions can accelerate progress, and priority should be given to those that offer promise of solving more than one problem at a time.
Behavior is a significant component of both the problems and their candidate solutions
Behavioral change comes about through education, so education should play a significant role in every proposed solution
Experimenting with new approaches and connecting the results can be accelerated by the using the vastly improved communication tools available through the internet.
Sharing “best practice” on the internet enables local groups seeking change to become aware of the “best practice” developed elsewhere, and help them avoid “reinventing the wheel.”
An Emergent Strategy for Improving Science Education
Today far too few young people learn about science. Part of the problem is that few of their teachers in school are comfortable with science, so doing a better job of training prospective teachers and making the teaching profession more attractive, for example by offering higher salaries to teachers and restricting the number of students in a given class, are two partial solutions, as is offering special incentives to existing and prospective science teachers.
Still another class of solutions is getting more scientists to become engaged in teaching young people about science outside the classroom: at schools, universities, and science museums; developing personal blogs; developing interactive web sites, such as http://emergentuniverse.org, http://iLearnScience.org or http://www.learner.org/courses/, which contain introductory materials on many different aspects of science; participating in special after-school programs like the LabRats Science Education Program [ "http://www.facebook.com/pages/Labrats-Science-Education-Program/305113940705">http://www.LabRats.org ] and the Wolf Ridge Environmental Learning Center [ http://www.wolf-ridge.org ]; and in programs on PBS, such as NOVA, and on the Discovery Channel, such as Mythbusters.
These partial solutions are an important part of an emergent strategy to improve science education, a strategy that should include: building connections between these different initiatives, so that the whole becomes greater than the simple sum of its parts; and pursuing synergies and experiments that can speed that improvement. Here are some examples: iLearnScience.org can bring the materials developed for LabRats to a much broader student audience, while their teachers can use these materials to improve their in-school science education; LabRats can develop lessons based on materials developed as supplements to NOVA or on materials for teachers developed by the Wolf Ridge Environmental Learning Center; NOVA could experiment with program-ending segments that spell out the gateways to emergent behavior presented in their programs; and Wolf Ridge teachers could use LabRats materials or those on iLearnScience.org in their classes.