Chapter One
In various sections of this book, important observations from diverse fields will be discussed—observations that cannot be accounted for and explained by mechanistic science and the traditional conceptual frameworks of psychiatry, psychology, anthropology, and medicine. Some of the new data are of such far-reaching significance that they indicate the need for a drastic revision of current understanding of human nature, and even the nature of reality. It seems, therefore, appropriate to start this book with an excursion into the philosophy of science by reviewing some modern ideas about the relationship between scientific theories and reality. Much of the resistance on the part of traditional scientists against the influx of new revolutionary data is based on a fundamental misunderstanding of the nature and function of scientific theories. In the last few decades, such philosophers and historians of science as Thomas Kuhn (1962), Philipp Frank (1974), Karl Popper (1963; 1965), and Paul Feyerabend (1978) have brought much clarity into this area. The pioneering work of these thinkers deserves a brief review here.
Since the Industrial Revolution, Western science has achieved astounding successes and has become a powerful force, shaping the lives of millions of people. Its materialistic and mechanistic orientations have all but replaced theology and philosophy as guiding principles of human existence and transformed to an unimaginable degree the world we live in. The technological triumphs have been so remarkable that, until quite recently, very few individuals questioned the absolute authority of science in determining the basic strategies of life. The textbooks of various disciplines tend to describe the history of science as a linear development with a gradual accumulation of knowledge about the universe that culminates in the present state of affairs. Important figures in the development of scientific thinking are thus presented as contributors who have worked on the same set of problems and according to the same set of fixed rules that the most recent achievements have established as scientific. Each period of the history of scientific ideas and methods is seen as a logical step in a gradual approximation to an increasingly accurate description of the universe and to the ultimate truth about existence.
Detailed analysis of the history and philosophy of science reveals that this is a grossly distorted and romanticized image of the actual course of events. One can make a very powerful and convincing argument that the history of science is far from linear and that, in spite of their technological successes, scientific disciplines do not necessarily bring us closer to an ever more accurate description of reality. The most prominent representative of this heretical point of view is the physicist and historian of science, Thomas Kuhn. His study of the development of scientific theories and revolutions in science was first inspired by his observation of certain fundamental differences between the social and natural sciences. He was struck by the number and extent of disagreements among social scientists concerning the basic nature of legitimate problems and approaches. This situation seemed to contrast sharply with that of the natural sciences. Although it was unlikely that practitioners of astronomy, physics, and chemistry would have firmer and more definitive answers than psychologists, anthropologists, and sociologists, the former for some reason did not seem to get involved in serious controversies over fundamental problems. Exploring this obvious discrepancy further, Kuhn launched an intensive study of the history of science that, after fifteen years, led to the publication of his ground-breaking work, The Structure of Scientific Revolutions (1962).
In the course of this research it became increasingly evident that, from a historical perspective, even the development of the so-called hard sciences is far from smooth and unambiguous. The history of science is by no means a process of gradual accumulation of data and formulation of ever more accurate theories. Instead, it shows a clearly cyclical nature with specific stages and characteristic dynamics. This process is lawful, and the changes involved can be understood and even predicted; the central concept of Kuhn’s theory, which makes this possible, is that of a paradigm. In the broadest sense, a paradigm can be defined as a constellation of beliefs, values, and techniques shared by the members of a given scientific community. Some paradigms are of a basic philosophical nature and are very general and encompassing, others govern scientific thinking in rather specific and circumscribed areas of research. A particular paradigm can thus be mandatory for all natural sciences; others for astronomy, physics, biochemistry, or molecular biology; yet others for such highly specialized and esoteric areas as the study of viruses or genetic engineering.1
A paradigm is as essential for science as are observation and experiment; adherence to specific paradigms is an absolutely indispensable prerequisite of any serious scientific endeavor. Reality is extremely complex and dealing with it in its totality is impossible. Science does not and cannot observe and take into consideration all the variables involved in a particular phenomenon, conduct all possible experiments, and perform all laboratory or clinical manipulations. The scientist must reduce the problem to a workable scale and his or her selection is guided by the leading paradigm of the time. Thus the scientist cannot avoid bringing a definite belief system into the area of study.
Scientific observations do not themselves clearly dictate unique and unambiguous solutions; no paradigm ever explains all available facts, and many different paradigms can theoretically account for the same set of data. Many factors determine which aspect of a complex phenomenon will be chosen and which of many conceivable experiments will be carried out or conducted first—accidents of investigation, basic education and specific training, prior experience in other fields, individual makeup, economic and political factors, and other variables. Observations and experiments can and must drastically reduce and restrict the range of acceptable scientific solutions; without this element, science would become science fiction. However, they cannot in and by themselves fully justify a particular interpretation or a belief system. It is thus, in principle, impossible to practice science without some set of a priori beliefs, fundamental metaphysical assumptions, and answers about the nature of reality and of human knowledge. However, the relative nature of any paradigm, no matter how advanced and convincingly articulated, should be clearly recognized and the scientist should not confuse it with the truth about reality.
According to Thomas Kuhn, paradigms play a crucial, complex, and ambiguous role in the history of science. Because of the above reasons, they are absolutely essential and indispensable for scientific progress. However, in certain stages of development they function as conceptual straitjackets that drastically interfere with the possibility of new discoveries and with the exploration of new areas of reality. In the history of science, the progressive and reactionary function of paradigms seems to oscillate in certain predictable patterns.
Early stages of most sciences, which Thomas Kuhn describes as “pre-paradigm periods,” have been characterized by conceptual chaos and competition among a large number of divergent views of nature. None of these can be clearly discarded as incorrect, since they are all roughly compatible with observations and with the scientific method of the time. A simple, elegant and plausible conceptualization of the data that seems to account well for the majority of available observations, and also holds promise as a guideline for future explorations, emerges out of this situation as the dominant paradigm.
When a paradigm is accepted by the majority of the scientific community, it becomes the mandatory way of approaching problems. At this point, it also tends to be mistaken for an accurate description of reality instead of being seen as a useful map, a convenient approximation, and a model for organizing currently available data. This confusion of the map with the territory is characteristic for the history of science. The limited knowledge of nature that has existed in successive historical periods has been seen by the practitioners of science of those times as a comprehensive image of reality that was incomplete only in details. This observation is so striking that it would be easy for a historian to present the development of science as a history of errors and idiosyncrasies rather than as a systematic accumulation of information and a gradual approximation to ultimate truth.
Once a paradigm has been accepted, it becomes a powerful catalyst of scientific progress; in Kuhn’s terminology, this stage is referred to as the “period of normal science.” Most scientists spend all their time pursuing normal science; consequently, in the past, this particular aspect of scientific activity has become synonymous with science itself. Normal science is predicated on the assumption that the scientific community knows what the universe is like. The leading theory defines not only what the world is, but also what it is not; it determines what is possible, as well as what is in principle impossible. Thomas Kuhn describes research as “a strenuous and devoted effort to force nature into the conceptual boxes supplied by professional education.” As long as the paradigm is taken for granted, only those problems will be considered legitimate that can be assumed to have solutions; this guarantees rapid success of normal science. Under these circumstances, the scientific community suppresses, often at a considerable cost, all novelties, because they are subversive to its basic commitments.
Paradigms have not only a cognitive, but also a normative influence; in addition to being statements about nature and reality, they also define the permissible problem field, determine the acceptable methods of approaching it, and set the standards of solution. Under the influence of a paradigm, all the fundamentals of science in a particular area become drastically redefined. Some problems that were seen as crucial might be declared irrelevant or unscientific, others are relegated to another discipline. Conversely, certain issues previously nonexistent or trivial may suddenly represent significant scientific factors or achievements. Even in areas where the old paradigm retains its validity, the understanding of the problems is not identical and requires translation and redefinition. Normal science based on the new paradigm is not only incompatible, but incommensurate with the practice governed by the previous one.
Normal science is essentially puzzle solving; its results are generally anticipated by the paradigm and it produces little novelty. The emphasis is on the way of achieving the results, and the objective is a further articulation of the leading paradigm, contributing to the scope and precision with which it can be applied. Normal research is, thus, cumulative, because scientists select only those problems that can be solved with conceptual and instrumental tools already in existence. Cumulative acquisition of fundamentally new knowledge under these circumstances is not only rare and unlikely, but improbable in principle. New discovery can appear only if the anticipations about nature and instruments based on the existing paradigm are failing. New theories cannot arise without destructive changes in the old beliefs about nature.
A really new and radical theory is never just an addition or increment to the existing knowledge. It changes basic rules, requires drastic revision or reformulation of the fundamental assumptions of prior theory, and involves re-evaluation of the existing facts and observations. According to Thomas Kuhn, only events of this nature represent true scientific revolutions. These can occur in certain limited fields of human knowledge or they can have a sweeping influence on a number of disciplines. The shifts from Aristotelian to Newtonian physics, or from Newtonian to Einsteinian physics, from the Ptolemaic geocentric system to the astronomy of Copernicus and Galileo, or from the phlogiston theory to Lavoisier’s chemistry are salient examples of changes of this kind. Each of them required rejection of a widely accepted and honored scientific theory in favor of another that was in principle incompatible with it. They all resulted in a drastic redefinition of the problems available and important for scientific exploration. In addition, they also redefined what should be considered an admissible problem and what should be the standards of a legitimate solution of a problem. This led to a drastic transformation of scientific imagination; it is not an exaggeration to say that the very perception of the world itself changed as a result of their impact.
Thomas Kuhn noted that scientific revolutions are preceded and heralded by a period of conceptual chaos in which the normal practice of science gradually changes into what he calls “extraordinary science.” Sooner or later, the everyday practice of normal science will necessarily lead to the discovery of anomalies. In many instances, certain pieces of equipment will fail to perform as anticipated by the paradigm, numerous observations accumulate that cannot be in any way accommodated by the existing belief system, or a problem that ought to be solved resists repeated efforts of prominent representatives of the profession.
As long as the paradigm exerts its spell on the scientific community, anomalies will not be sufficient to question the validity of basic assumptions. Initially, unexpected results tend to be labeled “bad research,” since the range of possible results is clearly defined by the paradigm. When the results are confirmed by the repeated experiments, this can lead to a crisis in the field. However, even then scientists do not renounce the paradigm that has led them into crisis. Once a scientific theory has achieved the status of a paradigm, it will not be declared invalid unless viable alternative is available. Lack of congruence between the postulates of a paradigm and observations of the world is not sufficient. For some time the discrepancy will be seen as a problem that might eventually be solved by future modifications and articulations.
However, when, after a period of tedious and fruitless effort, the anomaly suddenly emerges as more than just another puzzle, the discipline involved enters a period of extraordinary science. The best minds in the field concentrate their attention on the problem. The criteria for research tend to loosen up, and the experimenters become more open-minded and willing to consider daring alternatives. At this time, competing formulations proliferate and become increasingly divergent. The discontent with the existing paradigm grows and is expressed more and more explicitly. Scientists are willing to take recourse to philosophy and debate over fundamental assumptions—a situation that is inconceivable during periods of normal research. Before and during scientific revolutions there are also deep debates over legitimate methods, problems, and standards. Under these circumstances, in a state of growing crisis, professional insecurity increases. The failure of old rules leads to an intense search for new ones.
During the transition, there is an overlap between the problems that can be solved by the old and by the new paradigms. This is not surprising since philosophers of science have repeatedly demonstrated that more than one theoretical construct is always applicable to a given set of data. Scientific revolutions are those noncumulative episodes in which an older paradigm is replaced in its entirety, or in part, by a new one that is incompatible with it. The choice between two competing paradigms cannot be made by the use of evaluative procedures of normal science. The latter are a direct outgrowth of the old paradigm that is at issue, and their validity is critically dependent on the outcome of the argument. The function of the paradigm is thus of necessity circular; it can persuade but not convince by logical or even probabilistic arguments.
The two competing schools have a serious problem of communication or language. They operate on the basis of different basic postulates, assumptions about reality, and definitions of elementary concepts. As a result, they will not even agree as to what the important problems are, their nature is, and what would constitute their solution. Their criteria of science are not the same, their arguments are paradigm-dependent, and meaningful confrontation is impossible without intelligent translation. Within the new paradigm, the old terms are drastically redefined and receive a totally new meaning; as a result, they will appear to be related to each other in a very different way. The communication across the conceptual divide is only partial and confusing. Entirely different meanings of such concepts as matter, space, and time in the Newtonian and Einsteinian models could be used here as characteristic examples. At some point, a value judgment will also enter the field, since different paradigms differ in terms of which problems they solve and which questions they leave unanswered. The criteria for assessing this situation lie entirely outside the scope of normal science.
A scientist who is practicing normal science is essentially a problem solver. He takes the paradigm for granted and has no interest in testing its validity. As a matter, of fact, he or she has considerable investment in the preservation of its basic assumptions. In part this is based on understandable human motives, such as time and energy spent in past training or academic achievements closely linked with the exploitation of the paradigm at issue. However, the problem has much deeper roots and goes beyond human errors and emotional investment. It touches on the very nature of paradigms and their role for science.
An important part of this resistance is a deep reliance on the current paradigm as a true representation of reality and trust that it will ultimately solve all its problems. Thus, the resistance to the new paradigm is, in the last analysis, the very attitude that makes normal science possible. A scientist practicing normal science resembles a chess player whose problem-solving activity and capacity is critically dependent on a rigid set of rules. The objective of the game is to search for optimal solutions within the context of these a priori given rules; under these circumstances it would be absurd to consider questioning these rules, not to say changing them. The rules of the game are taken for granted in both instances, and they represent a necessary set of premises for the problem-solving activity. In science, novelty for its own sake is not desirable as it is in other creative fields.
Paradigm testing thus occurs only after persistent failure to solve an important puzzle has created a crisis and led to a competition of two rival paradigms. The new candidate for a paradigm has to meet certain important criteria to qualify. It must offer the solution to some crucial problems in areas where the old paradigm failed. In addition, the problem-solving capacity of its predecessor has to be preserved after the paradigm shift. It is also important for the new approach to promise additional problem solving in new areas. However, there are always losses as well as gains in scientific revolutions. The former are usually obscured and tacitly accepted, so long as progress is guaranteed.
Thus, Newtonian mechanics, unlike both the Aristotelian and Cartesian dynamics, did not explain the nature of the attractive forces between particles of matter, but simply took gravity for granted. This question was later addressed and answered by the general theory of relativity. Newton’s opponents saw in his reliance upon innate forces a return to the Dark Ages. Similarly, Lavoisier’s theory failed to answer the question why various metals are so much alike—one that had been successfully dealt with in the phlogiston theory. It was not until the twentieth century that science was again capable of tackling this issue. The opponents of Lavoisier also raised the objection that the rejection of “chemical principles” in favor of laboratory elements was a regression from established explanation to a mere name. Similarly, Einstein and other physicists opposed the dominant probabilistic interpretation of quantum physics.
The choice of the new paradigm does not occur in stages, step by step, under the inexorable impact of evidence and logic. It is an instant change, resembling psychological conversion or a shift in perception between figure and background, and it follows the all-or-none law. The scientists who embrace a new paradigm talk about an “Aha!” experience, sudden resolution, or a flash of illuminating intuition. The reasons why this happens are, obviously, rather complex. In addition to the paradigm’s capacity to rectify the situation that has led the old paradigm into crisis, Kuhn mentions motives of an irrational nature, biographically determined idiosyncrasies, prior reputation or nationality of the originator, and others. Also, the aesthetic qualities of the paradigm can play an important role, such as its elegance, simplicity, and beauty.
There has been a tendency in science to see the consequences of a paradigm shift in terms of a new interpretation of earlier data. According to this view, observations are unambiguously determined by the nature of the objective world and of the perceptual apparatus. However, this view is itself paradigm-dependent and is one of the basic assumptions of the Cartesian approach to the world. The raw data of observation are far from representing pure perception; stimuli should not be confused with perceptions or sensations. The latter are conditioned by experience, education, language, and culture. Under certain circumstances, the same stimuli can lead to different perceptions, and different stimuli to the same perceptions. The former can be exemplified by ambiguous pictures inviting a radical switch of perceptual gestalt. The most famous of these are the pictures that can be perceived in two different ways—e.g. as a duck or a rabbit, or as an antique vase or two human profiles, respectively. A good example of the latter is a person with inverted lenses who learns to correct the image of the world. There is no neutral language of observation based on retinal imprints only. The understanding of the nature of stimuli, of the sensory organs, and of their mutual interrelations reflects the existing theory of perception and of the human mind.
Rather than interpreting reality in a new way, a scientist who accepts a new paradigm is like a person putting on inverted lenses. Seeing the same objects and constellations of objects, and being aware that this is so, he or she will find them thoroughly transformed, in essence and in many of their details. It is not an exaggeration to say that, when a paradigm changes, the world of the scientists changes with it. They use new instruments, look into new places, observe different things, and perceive even familiar objects in an entirely new light. According to Kuhn, this radical shift of perception can be compared to a sudden transportation to another planet. Scientific fact and paradigm cannot be separated with absolute clarity. The world of the scientist is changed quantitatively and qualitatively by new developments of either fact or theory.
Figure-ground reversal is shown in the familiar goblet/silhouetted faces, introduced by Edgar Rubin in 1915.
The partisans of a revolutionary paradigm do not usually interpret the conceptual shift as a new, but ultimately relative, perception of reality. Once it occurs, there is a tendency to discard the old as wrong and welcome the new as accurate description. However, in a strict sense, none of the old theories were really wrong, so long as they were applied only to those phenomena that they could adequately explain. It was the generalization to other realms that was incorrect. Thus, according to Kuhn, old theories can be saved and maintained as correct when their range of application is restricted to only those phenomena and that precision of observation with which the experimental evidence in hand already deals. This implies that a scientist cannot speak “scientifically” and with authority about any phenomenon not already observed. Strictly speaking, it is not permissible to rely upon a paradigm whenever research enters a new area or seeks a degree of precision for which the theory offers no precedent. From this point of view, even the phlogiston theory could never have been disproved, had it not been generalized beyond the realm of phenomena that it could account for.
After a paradigm shift, the old theory can be seen in some sense as a special case of the new one, but it must be reformulated and transformed for that purpose. This revision can be undertaken only because the scientist can use the advantages of hindsight; it involves a change of the meaning of fundamental concepts. Thus, Newton’s mechanics can be reinterpreted as a special case of Einstein’s theory of relativity, and an explanation can be offered for its working within the limits of its applicability. Yet such basic concepts as space, time, and mass have been drastically changed and are not comparable. Newtonian mechanics maintains its validity, unless it claims applicability to high velocities or an unlimited accuracy of its descriptions and predictions. All historically significant theories showed congruence with the observed facts, even if only more or less. There is no conclusive answer on any level of scientific development whether, or to what degree, an individual theory corresponds accurately with the facts. However, it makes perfect sense to compare two paradigms and ask which of them better reflects the observed facts. In any case, paradigms should always be seen only as models, not as definitive descriptions of reality.
The acceptance of a new paradigm is seldom easy, since it depends on a variety of factors of emotional, political, and administrative nature and is not simply a matter of logical proof. Depending on the nature and scope of the paradigm, and on specific circumstances, it can take more than one generation before the new way of looking at the world is fully established in the scientific community. The statements of two great scientists provide illustrations. The first is a concluding passage of Charles Darwin’s Origin of Species (1859): “Although I am fully convinced of the truth of the views given in this volume. . . . I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. . . . But I look with confidence to the future—to young and rising naturalists who will be able to view both sides of the question with impartiality.” Even stronger is Max Planck’s comment in his Scientific Autobiography (1968): “. . . a new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”
Once the new paradigm is accepted and assimilated, its basic assumptions are incorporated into textbooks. Being sources of authority and pedagogical vehicles, these must be rewritten after each scientific revolution. By their very nature, they tend to disguise not only specifics, but also the very existence of the revolutions that produced them. Science is described as a series of individual discoveries and inventions that in their totality represent the modern body of knowledge. It thus appears that, from the very beginning, scientists have tried to achieve the objectives that are reflected in the latest paradigm. In their historical accounts, the texts tend to cover only those aspects of the work of individual scientists that can be seen as contributions to the contemporary point of view. Thus, in discussing Newton’s mechanics, they do not mention the role Newton attributed to God, or his deep interest in astrology and alchemy, which were integral to his philosophy. Similarly, one does not read that Descartes’ dualism of mind and body implied the existence of God. It is not usually mentioned in standard textbooks that many of the founders of modern physics, such as Einstein, Bohm, Heisenberg, Schroedinger, Bohr, and Oppenheimer not only found their work fully compatible with the mystical world view, but in a sense entered the mystical realms through their scientific pursuits. Once the textbooks are rewritten, science again appears to be a linear and cumulative enterprise, and the history of science seems to be characterized by gradual increments of knowledge. The role of human error and idiosyncrasy has been played down, and the cyclical dynamics of the paradigms with periodic shifts has been obscured. The field is prepared for secure practice of normal science, at least until the next accumulation of observations challenging the new paradigm.
Another important philosopher whose work is highly relevant in this connection is Philipp Frank. In his seminal work, Philosophy of Science (1974), he offered an incisive and detailed analysis of the relationship between observable facts and scientific theories. He succeeded in dispelling the myth that scientific theories can be logically derived from available facts and are unambiguously determined by observations of the phenomenal world. Using as historical examples the geometries of Euclid, Riemann, and Lobachevsky, Newton’s mechanics, Einstein’s theories of relativity and quantum physics, he provided remarkable insights into the nature and dynamics of scientific theories.
According to Frank, every scientific system is based on a small number of basic statements about reality, or axioms that are considered self-evident. The truth of the axioms is discovered, not by reasoning, but by direct intuition; they are products of the imaginative faculties of the mind rather than logic.2 By the application of a strict logical process it is possible to derive from the axioms a system of other statements, or theorems. The resulting theoretical system is of a purely logical nature; it is self-validating and its truth is essentially independent of the physical occurrences in the world. The relationship between such a system and the empirical observations must be tested to assess the degree of its practical applicability and correspondence. For this purpose, the elements of the theory must be described by “operational definitions,” in Bridgman’s sense.3 Only then can one determine the degree and limits of applicability of the theoretical system to material reality.
The intrinsic logical truth of Euclidean geometry, or of Newtonian mechanics, has not been destroyed by the discovery that their application to physical reality has specific limits. According to Frank, all hypotheses are essentially speculative. The difference between a purely philosophical hypothesis and a scientific one is that the latter can be tested. It is no longer important that a scientific theory appeals to common sense; this requirement was discarded by Galileo Galilei. It can be fantastic and absurd, as long as its testing can be done on the level of common experience.
Conversely, a direct statement about the nature of the universe that cannot be subjected to experimental testing is pure metaphysical speculation and not a scientific theory. Such statements as, “All existing things are of a material nature and there is no spiritual world,” or, “Consciousness is a product of matter,” clearly belong to this category, no matter how self-evident they might appear to common sense or to a mechanistic scientist.
The most radical criticism of scientific methodology and its current practices was formulated by Paul Feyerabend. In his explosive book, Against Method: Outline of an Anarchistic Theory of Knowledge (1978), he argued emphatically that science is not and cannot be governed by a system of firm, unchanging, and absolute principles. History provides unambiguous evidence that science is essentially an anarchistic enterprise. Violations of the basic epistemological rules have not been mere accidental events; throughout history they have been absolutely necessary for scientific progress. The most successful scientific inquiries have never proceeded according to the rational method. In the history of science in general, and in the time of great revolutions in particular, a more determined application of the canons of current scientific method would not have accelerated the development; it would have brought it to a standstill. The Copernican revolution and other essential developments in modern science have survived only because reason was frequently overruled in the past.
The so-called consistency condition, which demands that a new hypothesis agrees with accepted ones, is unreasonable and counterproductive. It eliminates a hypothesis not because it disagrees with facts, but because it is in conflict with another theory. As a result, it tends to protect and preserve the theory that is older, not the one that is better. Hypotheses contradicting well-established theories give us evidence that cannot be obtained in any other way. Facts and theories are more intimately connected than conventional science has assumed, and certain facts cannot be unearthed without the help of alternatives to the established theories.
When discussing questions of testing, it is imperative to use a whole set of overlapping, factually adequate, but mutually inconsistent theories. The invention of alternatives to the view at the center of a discussion constitutes an essential part of the empirical method. It is not sufficient to compare theories with observations and facts. Data obtained in the context of a particular conceptual system are not independent of the basic theoretical and philosophical assumptions of this system. A truly scientific comparison of two theories has to treat “facts” and “observations” in the context of the theory that is being tested.
Since the facts, observations, and even criteria for evaluation are “paradigm-bound,” the most important formal properties of a theory are found by contrast, not by analysis. If the scientist wants to maximize the empirical content of the view he or she holds, it is mandatory to use pluralistic methodology—to introduce rival theories and compare ideas with ideas rather than with experience.
There is no idea or system of thought, however ancient or seemingly absurd, that is not capable of improving our knowledge. Thus, ancient spiritual systems and aboriginal myths appear strange and nonsensical only because their scientific content is either unknown or is distorted by anthropologists or philologists unfamiliar with the simplest physical, medical, or astronomical knowledge. In science, reason cannot be universal and the irrational cannot be entirely excluded. There is not a single interesting theory that agrees with all the facts in its domain. We find that all theories fail to reproduce certain quantitative results and that they are qualitatively incompetent to a surprising degree.
All methodologies, even the most obvious ones, have their limits. New theories are initially restricted to a fairly narrow domain of facts and are only slowly extended to other areas. The mode of this extension is rarely determined by the elements that constitute the content of its predecessors. The emerging conceptual apparatus of the new theory soon starts defining its own problems and problem areas. Many earlier questions, facts, and observations that make sense only in the abandoned context appear suddenly silly and irrelevant; they are either forgotten or pushed aside. And, conversely, a host of entirely new issues emerges as problems of critical importance.
The above discussion of scientific revolutions, of the dynamics of paradigms, and of the function of theories in science might leave the contemporary reader with the impression that the relevance of this work is primarily historical. It would be easy to assume that the last major conceptual upheaval took place in the early decades of this century, and that the next scientific revolution will occur some time in the remote future. To the contrary, the central message of this book is that Western science is approaching a paradigm shift of unprecedented proportions, one that will change our concepts of reality and of human nature, bridge the gap between ancient wisdom and modern science, and reconcile the difference between Eastern spirituality and Western pragmatism.