The Tao of Physics

In Japan, there exists yet another mode of expressing philosophical views which should be mentioned. It is a special form of extremely concise poetry which is often used by Zen masters to point directly at the ‘suchness’ of reality. When a monk asked Fuketsu Ensho, When speech and silence are both inadmissible, how can one pass without error?’ the master replied:

I always remember Kiangsu in March—

The cry of the partridge,

The mass of fragrant flowers.18

This form of spiritual poetry has reached its perfection in the haiku, a classical Japanese verse of just seventeen syllables, which was deeply influenced by Zen. The insight into the very nature of Life reached by these haiku poets comes across even in the English translation:

Leaves falling

Lie on one another;

The rain beats the rain.19

Whenever the Eastern mystics express their knowledge in words—be it with the help of myths, symbols, poetic images or paradoxical statements—they are well aware of the limitations imposed by language and ‘linear’ thinking. Modern physics has come to take exactly the same attitude with regard to its verbal models and theories. They, too, are only approximate and necessarily inaccurate. They are the counterparts of the Eastern myths, symbols and poetic images, and it is at this level that I shall draw the parallels. The same idea about matter is conveyed, for example, to the Hindu by the cosmic dance of the god Shiva as to the physicist by certain aspects of quantum field theory. Both the dancing god and the physical theory are creations of the mind: models to describe their authors’ intuition of reality.

Chapter 3 Beyond Language

The contradiction so puzzling to the ordinary way of thinking comes from the fact that we have to use language to communicate our inner experience which in its very nature transcends linguistics.

D. T. Suzuki

The problems of language here are really serious. We wish to speak in some way about the structure of the atoms … But we cannot speak about atoms in ordinary language.

W. Heisenberg

The notion that all scientific models and theories are approximate and that their verbal interpretations always suffer from the inaccuracy of our language was already commonly accepted by scientists at the beginning of this century, when a new and completely unexpected development took place. The study of the world of atoms forced physicists to realize that our common language is not only inaccurate, but totally inadequate to describe the atomic and subatomic reality. Quantum theory and relativity theory, the two bases of modern physics, have made it clear that this reality transcends classical logic and that we cannot talk about it in ordinary language. Thus Heisenberg writes:

The most difficult problem … concerning the use of the language arises in quantum theory. Here we have at first no simple guide for correlating the mathematical symbols with concepts of ordinary language; and the only thing we know from the start is the fact that our common concepts cannot be applied to the structure of the atoms.1

From a philosophical point of view, this has certainly been the most interesting development in modern physics, and here lies one of the roots of its relation to Eastern philosophy. In the schools of Western philosophy, logic and reasoning have always been the main tools used to formulate philosophical ideas and this is true, according to Bertrand Russell, even of religious philosophies. In Eastern mysticism, on the other hand, it has always been realized that reality transcends ordinary language, and the sages of the East were not afraid to go beyond logic and common concepts. This is the main reason, I think, why their models of reality constitute a more appropriate philosophical background to modern physics than the models of Western philosophy.

The problem of language encountered by the Eastern mystic is exactly the same as the problem the modern physicist faces. In the two passages quoted at the beginning of this chapter, D. T. Suzuki speaks about Buddhism2 and Werner Heisenberg speaks about atomic physics,3 and yet the two passages are almost identical. Both the physicist and the mystic want to communicate their knowledge, and when they do so with words their statements are paradoxical and full of logical contradictions. These paradoxes are characteristic of all mysticism, from Heraclitus to Don Juan, and since the beginning of this century they are also characteristic of physics.

In atomic physics, many of the paradoxical situations are connected with the dual nature of light or—more generally—of electromagnetic radiation. On the one hand, it is clear that this radiation must consist of waves because it produces the well-known interference phenomena associated with waves: when there are two sources of light, the intensity of the light to be found at some other place will not necessarily be just the sum of that which comes from the two sources, but may be more or less. This can easily be explained by the interference of the waves emanating from the two sources: in those places where two crests coincide we shall have more light than the sum of the two; where a crest and a trough coincide we shall have less. The precise amount of interference can easily be calculated. Interference phenomena of this kind can be observed whenever one deals with electromagnetic radiation, and force us to conclude that this radiation consists of waves.

On the other hand, electromagnetic radiation also produces the so-called photoelectric effect: when ultraviolet light is shone on the surface of some metals it can ‘kick out’ electrons from the surface of the metal, and therefore it must consist of moving particles. A similar situation occurs in the ‘scattering’ experiments of X-rays. These experiments can only be interpreted correctly if they are described as collisions of ‘light particles’ with electrons. And yet, they show the interference patterns characteristic of waves. The question which puzzled physicists so much in the early stages of atomic theory was how electromagnetic radiation could simultaneously consist of particles (i.e. of entities confined to a very small volume) and of waves, which are spread out over a large area of space. Neither language nor imagination could deal with this kind of reality very well.

Eastern mysticism has developed several different ways of dealing with the paradoxical aspects of reality. Whereas they are bypassed in Hinduism through the use of mythical language, Buddhism and Taoism tend to emphasize the paradoxes rather than conceal them. The main Taoist scripture, Lao Tzu’s Tao Te Ching, is written in an extremely puzzling, seemingly illogical style. It is full of intriguing contradictions and its compact, powerful, and extremely poetic language is meant to arrest the reader’s mind and throw it off its familiar tracks of logical reasoning.

Chinese and Japanese Buddhists have adopted this Taoist technique of communicating the mystical experience by simply exposing its paradoxical character. When the Zen master Daito saw the Emperor Godaigo, who was a student of Zen, the master said:

We were parted many thousands of kalpas ago, yet we have not been separated even for a moment. We are facing each other all day long, yet we have never met.4

Zen Buddhists have a particular knack for making a virtue out of the inconsistencies arising from verbal communication, and with the koan system they have developed a unique way of transmitting their teachings completely non-verbally. Koans are carefully devised nonsensical riddles which are meant to make the student of Zen realize the limitations of logic and reasoning in the most dramatic way. The irrational wording and paradoxical content of these riddles makes it impossible to solve them by thinking. They are designed precisely to stop the thought process and thus to make the student ready for the non-verbal experience of reality. The contemporary Zen master Yasutani introduced a Western student to one of the most famous koans with the following words:

One of the best koans, because the simplest, is Mu. This is its background: A monk came to Joshu, a renowned Zen master in China hundreds of years ago, and asked: ‘Has a dog Buddha-nature or not?’ Joshu retorted, ‘Mu!’ Literally, the expression means ‘no’ or ‘not’, but the significance of Joshu’s answer does not lie in this. Mo is the expression of the living, functioning, dynamic Buddha-nature. What you must do is discover the spirit or essence of this Mu, not through intellectual analysis but by search into your innermost being. Then you must demonstrate before me, concretely and vividly, that you understand Mu as living truth, without recourse to conceptions, theories, or abstract explanations. Remember, you can’t understand Mu through ordinary cognition, you must grasp it directly with your whole being.5

To a beginner, the Zen master will normally present either this Mu-koan or one of the following two:

‘What was your original face—the one you had before your parents gave birth to you?’

‘You can make the sound of two hands clapping. Now what is the sound of one hand?’

All these koans have more or less unique solutions which a competent master recognizes immediately. Once the solution is found, the koan ceases to be paradoxical and becomes a profoundly meaningful statement made from the state of consciousness which it has helped to awaken.

In the Rinzai school, the student has to solve a long series of koans, each of them dealing with a particular aspect of Zen. This is the only way this school transmits its teachings. It does not use any positive statements, but leaves it entirely to the student to grasp the truth through the koans.

Here we find a striking parallel to the paradoxical situations which confronted physicists at the beginning of atomic physics. As in Zen, the truth was hidden in paradoxes that could not be solved by logical reasoning, but had to be understood in the terms of a new awareness; the awareness of the atomic reality. The teacher here was, of course, nature, who, like the Zen masters, does not provide any statements. She just provides the riddles.

The solving of a koan demands a supreme effort of concentration and involvement from the student. In books about Zen we read that the koan grips the student’s heart and mind and creates a true mental impasse, a state of sustained tension in which the whole world becomes an enormous mass of doubt and questioning. The founders of quantum theory experienced exactly the same situation, described here most vividly by Heisenberg:

I remember discussions with Bohr which went through many hours till very late at night and ended almost in despair; and when at the end of the discussion I went alone for a walk in the neighbouring park I repeated to myself again and again the question: Can nature possibly be so absurd as it seemed to us in these atomic experiments?6

Whenever the essential nature of things is analysed by the intellect, it must seem absurd or paradoxical. This has always been recognized by the mystics, but has become a problem in science only very recently. For centuries, scientists were searching for the ‘fundamental laws of nature’ underlying the great variety of natural phenomena. These phenomena belonged to the scientists’ macroscopic environment and thus to the realm of their sensory experience. Since the images and intellectual concepts of their language were abstracted from this very experience, they were sufficient and adequate to describe the natural phenomena.

Questions about the essential nature of things were answered in classical physics by the Newtonian mechanistic model of the universe which, much in the same way as the Democritean model in ancient Greece, reduced all phenomena to the motions and interactions of hard indestructible atoms. The properties of these atoms were abstracted from the macroscopic notion of billiard balls, and thus from sensory experience. Whether this notion could actually be applied to the world of atoms was not questioned. Indeed, it could not be investigated experimentally.

In the twentieth century, however, physicists were able to tackle the question about the ultimate nature of matter experimentally. With the help of a most sophisticated technology they were able to probe deeper and deeper into nature, uncovering one layer of matter after the other in search for its ultimate ‘building blocks’. Thus the existence of atoms was verified, then their constituents were discovered—the nuclei and electrons—and finally the components of the nucleus—the protons and neutrons—and many other subatomic particles.

The delicate and complicated instruments of modern experimental physics penetrate deep into the submicroscopic world, into realms of nature far removed from our macroscopic environment, and make this world accessible to our senses. However, they can do so only through a chain of processes ending, for example, in the audible click of a Geiger counter, or in a dark spot on a photographic plate. What we see, or hear, are never the investigated phenomena themselves but always their consequences. The atomic and subatomic world itself lies beyond our sensory perception.

It is, then, with the help of modern instrumentation that we are able to ‘observe’ the properties of atoms and their constituents in an indirect way, and thus to ‘experience’ the subatomic world to some extent. This experience, however, is not an ordinary one, comparable to that of our daily environment. The knowledge about matter at this level is no longer derived from direct sensory experience, and therefore our ordinary language, which takes its images from the world of the senses, is no longer adequate to describe the observed phenomena. As we penetrate deeper and deeper into nature, we have to abandon more and more of the images and concepts of ordinary language.

On this journey to the world of the infinitely small, the most important step, from a philosophical point of view, was the first one: the step into the world of atoms. Probing inside the atom and investigating its structure, science transcended the limits of our sensory imagination. From this point on, it could no longer rely with absolute certainty on logic and common sense. Atomic physics provided the scientists with the first glimpses of the essential nature of things. Like the mystics, physicists were now dealing with a nonsensory experience of reality and, like the mystics, they had to face the paradoxical aspects of this experience. From then on therefore, the models and images of modern physics became akin to those of Eastern philosophy.

Chapter 4 The New Physics

According to the Eastern mystics, the direct mystical experience of reality is a momentous event which shakes the very foundations of one’s world view. D. T. Suzuki has called it ‘the most startling event that could ever happen in the realm of human consciousness … upsetting every form of standardised experience’,1 and he has illustrated the shocking character of this experience with the words of a Zen master who described it as ‘the bottom of a pail breaking through’.

Physicists, at the beginning of this century, felt much the same way when the foundations of their world view were shaken by the new experience of the atomic reality, and they described this experience in terms which were often very similar to those used by Suzuki’s Zen master. Thus Heisenberg wrote:

The violent reaction on the recent development of modern physics can only be understood when one realises that here the foundations of physics have started moving; and that this motion has caused the feeling that the ground would be cut from science.2

Einstein experienced the same shock when he first came in contact with the new reality of atomic physics. He wrote in his autobiography:

All my attempts to adapt the theoretical foundation of physics to this (new type of) knowledge failed completely. It was as if the ground had been pulled out from under one, with no firm foundation to be seen anywhere, upon which one could have built.3

The discoveries of modern physics necessitated profound changes of concepts like space, time, matter, object, cause and effect, etc., and since these concepts are so basic to our way of experiencing the world it is not surprising that the physicists who were forced to change them felt something of a shock. Out of these changes emerged a new and radically different world view, still in the process of formation by current scientific research.

It seems, then, that Eastern mystics and Western physicists went through similar revolutionary experiences which led them to completely new ways of seeing the world. In the following two passages, the European physicist Niels Bohr and the Indian mystic Sri Aurobindo both express the depth and the radical character of this experience.

The great extension of our experience in recent years has brought to light the insufficiency of our simple mechanical conceptions and, as a consequence, has shaken the foundation on which the customary interpretation of observation was based.4

Niels Bohr

All things in fact begin to change their nature and appearance; one’s whole experience of the world is radically different … There is a new vast and deep way of experiencing seeing knowing contacting things.5

Sri Aurobindo

This chapter will serve to sketch a preliminary picture of this new conception of the world against the contrasting background of classical physics;* showing how the classical mechanistic world view had to be abandoned at the beginning of this century when quantum theory and relativity theory—the two basic theories of modern physics—forced us to adopt a much more subtle, holistic and ‘organic’ view of nature.

CLASSICAL PHYSICS

The world view which was changed by the discoveries of modern physics had been based on Newton’s mechanical model of the universe. This model constituted the solid framework of classical physics. It was indeed a most formidable foundation supporting, like a mighty rock, all of science and providing a firm basis for natural philosophy for almost three centuries.

The stage of the Newtonian universe, on which all physical phenomena took place, was the three-dimensional space of classical Euclidean geometry. It was an absolute space, always at rest and unchangeable. In Newton’s own words, ‘Absolute space, in its own nature, without regard to anything external, remains always similar and immovable.’6 All changes in the physical world were described in terms of a separate dimension, called time, which again was absolute, having no connection with the material world and flowing smoothly from the past through the present to the future. ‘Absolute, true, and mathematical time,’ said Newton, ‘of itself and by its own nature, flows uniformly, without regard to anything external.’7

The elements of the Newtonian world which moved in this absolute space and absolute time were material particles. In the mathematical equations they were treated as ‘mass points’ and Newton saw them as small, solid, and indestructible objects out of which all matter was made. This model was quite similar to that of the Greek atomists. Both were based on the distinction between the full and the void, between matter and space, and in both models the particles remained always identical in their mass and shape. Matter was therefore always conserved and essentially passive. The important difference between the Democritean and Newtonian atomism is that the latter includes a precise description of the force acting between the material particles. This force is very simple, depending only on the masses and the mutual distances of the particles. It is the force of gravity, and it was seen by Newton as rigidly connected with the bodies it acted upon, and as acting instantaneously over a distance. Although this was a strange hypothesis, it was not investigated further. The particles and the forces between them were seen as created by God and thus were not subject to further analysis. In his Opticks, Newton gives us a clear picture of how he imagined God’s creation of the material world:

It seems probable to me that God in the beginning formed matter in solid, massy, hard, impenetrable, movable particles, of such sizes and figures, and with such other properties, and in such proportion to space, as most conduced to the end for which he formed them; and that these primitive particles being solids, are incomparably harder than any porous bodies compounded of them; even so very hard, as never to wear or break in pieces; no ordinary power being able to divide what God himself made one in the first creation.8

All physical events are reduced, in Newtonian mechanics, to the motion of material points in space, caused by their mutual attraction, i.e. by the force of gravity. In order to put the effect of this force on a mass point into a precise mathematical form, Newton had to invent completely new concepts and mathematical techniques, those of differential calculus. This was a tremendous intellectual achievement and has been praised by Einstein as ‘perhaps the greatest advance in thought that a single individual was ever privileged to make’.

Newton’s equations of motion are the basis of classical mechanics. They were considered to be fixed laws according to which material points move, and were thus thought to account for all changes observed in the physical world. In the Newtonian view, God had created, in the beginning, the material particles, the forces between them, and the fundamental laws of motion. In this way, the whole universe was set in motion and it has continued to run ever since, like a machine, governed by immutable laws.

The mechanistic view of nature is thus closely related to a rigorous determinism. The giant cosmic machine was seen as being completely causal and determinate. All that happened had a definite cause and gave rise to a definite effect, and the future of any part of the system could—in principle—be predicted with absolute certainty if its state at any time was known in all details. This belief found its clearest expression in the famous words of the French mathematician Pierre Simon Laplace:

An intellect which at a given instant knew all the forces acting in nature, and the position of all things of which the world consists—supposing the said intellect were vast enough to subject these data to analysis—would embrace in the same formula the motions of the greatest bodies in the universe and those of the slightest atoms; nothing would be uncertain for it, and the future, like the past, would be present to its eyes.9

The philosophical basis of this rigorous determinism was the fundamental division between the I and the world introduced by Descartes. As a consequence of this division, it was believed that the world could be described objectively, i.e. without ever mentioning the human observer, and such an objective description of nature became the ideal of all science.

The eighteenth and nineteenth centuries witnessed a tremendous success of Newtonian mechanics. Newton himself applied his theory to the movement of the planets and was able to explain the basic features of the solar system. His planetary model was greatly simplified, however, neglecting, for example, the gravitational influence of the planets on each other, and thus he found that there were certain irregularities which he could not explain. He resolved this problem by assuming that God was always present in the universe to correct these irregularities.

Laplace, the great mathematician, set himself the ambitious task of refining and perfecting Newton’s calculations in a book which should ‘offer a complete solution of the great mechanical problem presented by the solar system, and bring theory to coincide so closely with observation that empirical equations would no longer find a place in astronomical tables’.10 The result was a large work in five volumes, called Mécanique Céleste in which Laplace succeeded in explaining the motions of the planets, moons and comets down to the smallest details, as well as the flow of the tides and other phenomena related to gravity. He showed that the Newtonian laws of motion assured the stability of the solar system and treated the universe as a perfectly self-regulating machine. When Laplace presented the first edition of his work to Napoleon—so the story goes—Napoleon remarked, ‘Monsieur Laplace, they tell me you have written this large book on the system of the universe, and have never even mentioned its Creator.’ To this Laplace replied bluntly, ‘I had no need for that hypothesis.’