Authors: Michio Kaku,Robert O'Keefe
Webster’s Collegiate Dictionary
defines
holism
as the “theory that the determining factors esp. in living nature are irreducible wholes.” This philosophy maintains that the Western philosophy of breaking things down into their components is overly simplistic, that one misses the larger picture, which may contain vitally important information. For example, think of an ant colony containing thousands of ants that obeys complex, dynamic rules of social behavior. The question is: What is the best way to understand the behavior of an ant colony? The reductionist would break the ants into their constituents: organic molecules. However, one may spend hundreds of years dissecting ants and analyzing their molecular makeup without finding the simplest clues as to how an ant colony behaves. The obvious way is to analyze the behavior of an ant colony as an integral whole, without breaking it down.
Similarly, this debate has sparked considerable controversy within the area of brain research and artificial intelligence. The reductionist approach is to reduce the brain to its ultimate units, the brain cells, and try to reassemble the brain from them. A whole school of research in artificial intelligence held that by creating elemental digital circuits we could build up increasingly complex circuits, until we created artificial intelligence. Although this school of thought had initial success in the 1950s by modeling “intelligence” along the lines of modern digital computers,
it proved disappointing because it could not mimic even the simplest of brain functions, such as recognizing patterns in a photograph.
The second school of thought has tried to take a more holistic approach to the brain. It attempts to define the functions of the brain and create models that treat the brain as a whole. Although this has proved more difficult to initiate, it holds great promise because certain brain functions that we take for granted (for example, tolerance of error, weighing of uncertainty, and making creative associations between different objects) are built into the system from the start. Neural network theory, for example, uses aspects of this organic approach.
Each side of this reductionist-holistic debate takes a dim view of the other. In their strenuous attempts to debunk each other, they sometimes only diminish themselves. They often talk past each other, not addressing each other’s main points.
The latest twist in the debate is that the reductionists have, for the past few years, declared victory over holism. Recently, there has been a flurry of claims in the popular press by the reductionists that the successes of the Standard Model and the GUT theory are vindications of reducing nature to smaller and more basic constituents. By probing down to the elemental quarks, leptons, and Yang-Mills fields, physicists have finally isolated the basic constituents of all matter. For example, physicist James S. Trefil of the University of Virginia takes a swipe at holism when he writes about the “Triumph of Reductionism”:
During the 1960s and 1970s, when the complexity of the particle world was being made manifest in one experiment after another, some physicists broke faith with the reductionist philosophy and began to look outside of the Western tradition for guidance. In his book
The Tao of Physics
, for example, Fritjhof Capra argued that the philosophy of reductionism had failed and that it was time to take a more holistic, mystical view of nature…. [T]he 1970s [however] can be thought of as the period in which the great traditions of Western scientific thought, seemingly imperiled by the advances of twentieth-century science, have been thoroughly vindicated. Presumably, it will take a while for this realization to percolate away from a small group of theoretical physicists and become incorporated into our general world view.
5
The disciples of holism, however, turn this debate around. They claim that the idea of unification, perhaps the greatest theme in all of physics, is holistic, not reductionist. They point to how reductionists
would sometimes snicker behind Einstein’s back in the last years of his life, saying that he was getting senile trying to unite all the forces of the world. The discovery of unifying patterns in physics was an idea pioneered by Einstein, not the reductionists. Furthermore, the inability of the reductionists to offer a convincing resolution of the Schrödinger’s cat paradox shows that they have simply chosen to ignore the deeper, philosophical questions. The reductionists may have had great success with quantum field theory and the Standard Model, but ultimately that success is based on sand, because quantum theory, in the final analysis, is an incomplete theory.
Both sides, of course, have merit. Each side is merely addressing different aspects of a difficult problem. However, taken to extremes, this debate sometimes degenerates into a battle between what I call belligerent science versus know-nothing science.
Belligerent science clubs the opposition with a heavy, rigid view of science that alienates rather than persuades. Belligerent science seeks to win points in a debate, rather than win over the audience. Instead of appealing to the finer instincts of the lay audience by presenting itself as the defender of enlightened reason and sound experiment, it comes off as a new Spanish Inquisition. Belligerent science is science with a chip on its shoulder. Its scientists accuse the holists of being soft-headed, of getting their physics confused, of throwing pseudoscientific gibberish to cover their ignorance. Thus belligerent science may be winning the individual battles, but is ultimately losing the war. In every one-on-one skirmish, belligerent science may trounce the opposition by parading out mountains of data and learned Ph.D.s. However, in the long run, arrogance and conceit may eventually backfire by alienating the very audience that it is trying to persuade.
Know-nothing science goes to the opposite extreme, rejecting experiment and embracing whatever faddish philosophy happens to come along. Know-nothing science sees unpleasant facts as mere details, and the overall philosophy as everything. If the facts do not seem to fit the philosophy, then obviously something is wrong with the facts. Know-nothing science comes in with a preformed agenda, based on personal fulfillment rather than objective observation, and tries to fit in the science as an afterthought.
This split between these two factions first appeared during the Vietnam War, when the flower generation was appalled by the massive, excessive use of deadly technology against a peasant nation. But perhaps the area in which this legitimate debate has flared up most recently is personal health. For example, well-paid lobbyists for the powerful agri-business
and food industry in the 1950s and 1960s exerted considerable influence on Congress and the medical establishment, preventing a thorough examination of the harmful effects of cholesterol, tobacco, animal fats, pesticides, and certain food additives on heart disease and cancer, which have now been thoroughly documented.
A recent example is the scandal that surrounded the uproar over the pesticide Alar in apples. When the environmentalists at the National Resources Defense Council announced that current levels of pesticides in apples could kill upward of 5,000 children, they sparked concern among consumers and indignation within the food industry, which denounced them as alarmists. Then it was revealed that the report used figures and data from the federal government to arrive at these conclusions. This, in turn, implied that the Food and Drug Administration was sacrificing 5,000 children in the interests of “acceptable risk.”
In addition, the revelations about the widespread possible contamination of our drinking water by lead, which can cause serious neurological problems in children, only served to lower the prestige of science in the minds of most Americans. The medical profession, the food industry, and the chemical industry have begun to earn the distrust of wide portions of society. These and other scandals have also contributed to the national flareup of faddish health diets, most of which are well intentioned, but some of which are not scientifically sound.
These two philosophical viewpoints, apparently irreconcilable, must be viewed from the larger perspective. They are antagonistic only when viewed in their extreme form.
Perhaps a higher synthesis of both viewpoints lies in higher dimensions. Geometry, almost by definition, cannot fit the usual reductionist mode. By studying a tiny strand of fiber, we cannot possibly understand an entire tapestry. Similarly, by isolating a microscopic region of a surface, we cannot determine the overall structure of the surface. Higher dimensions, by definition, imply that we must take the larger, global viewpoint.
Similarly, geometry is not purely holistic, either. Simply observing that a higher-dimensional surface is spherical does not provide the information necessary to calculate the properties of the quarks contained within it. The precise way in which a dimension curls up into a ball determines the nature of the symmetries of the quarks and gluons living
on that surface. Thus holism by itself does not give us the data necessary to turn the ten-dimensional theory into a physically relevant theory.
The geometry of higher dimensions, in some sense, forces us to realize the unity between the holistic and reductionist approaches. They are simply two ways of approaching the same thing: geometry. They are two sides of the same coin. From the vantage point of geometry, it makes no difference whether we approach it from the reductionist point of view (assembling quarks and gluons in a Kaluza-Klein space) or the holistic approach (taking a Kaluza-Klein surface and discovering the symmetries of the quarks and gluons).
We may prefer one approach over the other, but this is only for historical or pedagogical purposes. For historical reasons, we may stress the reductionist roots of subatomic physics, emphasizing how particle physicists over a period of 40 years pieced together three of the fundamental forces by smashing atoms, or we may take a more holistic approach and claim that the final unification of quantum forces with gravity implies a deep understanding of geometry. This leads us to approach particle physics through Kaluza-Klein and string theories and to view the Standard Model as a consequence of curling up higher-dimensional space.
The two approaches are equally valid. In our book
Beyond Einstein: The Cosmic Quest for the Theory of the Universe
, Jennifer Trainer and I took a more reductionist approach and described how the discoveries of phenomena in the visible universe eventually led to a geometric description of matter. In this book, we took the opposite approach, beginning with the invisible universe and taking the concept of how the laws of nature simplify in higher dimensions as our basic theme. However, both approaches yield the same result.
By analogy, we can discuss the controversy over the “left” brain and “right” brain. The neurologists who originally made the experimental discovery that the left and right hemispheres of our brain perform distinctly different functions became distressed that their data were grossly misrepresented in the popular press. Experimentally, they found that when someone is shown a picture, the left eye (or right brain) pays more attention to particular details, while the right eye (or left brain) more easily grasps the entire photo. However, they became disturbed when popularizers began to say that the left brain was the “holistic brain” and the right brain was the “reductionist brain.” This took the distinction between the two brains out of context, resulting in many bizarre interpretations of how one should organize one’s thoughts in daily life.
A more correct approach to brain function, they found, was that the
brain necessarily uses both halves in synchrony, that the dialectic between both halves of the brain is more important than the specific function of each half individually. The truly interesting dynamics take place when both halves of the brain interact in harmony.
Similarly, anyone who sees the victory of one philosophy over the other in recent advances in physics is perhaps reading too much into the experimental data. Perhaps the safest conclusion that we can reach is that science benefits most from the intense interaction between these two philosophies.
Let us see concretely how this takes place, analyzing how the theory of higher dimensions gives us a resolution between diametrically opposed philosophies, using two examples, Schrödinger’s cat and the
S
matrix theory.
The disciples of holism sometimes attack reductionism by hitting quantum theory where it is weakest, on the question of Schrödinger’s cat. The reductionists cannot give a reasonable explanation of the paradoxes of quantum mechanics.
The most embarrassing feature of quantum theory, we recall, is that an observer is necessary to make a measurement. Thus before the observation is made, cats can be either dead or alive and the moon may or may not be in the sky. Usually, this would be considered crazy, but quantum mechanics has been verified repeatedly in the laboratory. Since the process of making an observation requires an observer, and since an observer requires consciousness, then the disciples of holism claim that a cosmic consciousness must exist in order to explain the existence of any object.
Higher-dimensional theories do not resolve this difficult question completely, but they certainly put it in a new light. The problem lies in the distinction between the observer and the observed. However, in quantum gravity we write down the wave function of the entire universe. There is no more distinction between the observer and the observed; quantum gravity allows for the existence of only the wave function of everything.
In the past, such statements were meaningless because quantum gravity did not really exist as a theory. Divergences would crop up every time someone wanted to do a physically relevant calculation. So the concept of a wave function for the entire universe, although appealing, was meaningless.
However, with the coming of the ten-dimensional theory, the meaning of the wave function of the entire universe becomes a relevant concept once again. Calculations with the wave function of the universe can appeal to the fact that the theory is ultimately a ten-dimensional theory, and is hence renormalizable.