Normativity in the physical sciences

P.H. Stoker

School of Physics

PU for CHE

Potchefstroom

1. Introduction

Empirical science is a type of knowledge, that relies on observation and experiment. As a science, it is based on logical relations between concepts, as expressions of a worldview. The norm of doing science is determined by coherent traditions of scientific research (Kuhn, 1970). Historically, traditions may be described by ‘Copernican’ astronomy, ‘Aristotelian’ or ‘Newtonian’ dynamics, ‘corpuscular’ or ‘wave’ optics, and so on. Scientific traditions are bound to philosophical preconceptions, based on prevailing worldviews. ‘Normal science’ is defined by Thomas Kuhn (1970) to mean research firmly based upon one or more past scientific achievements, achievements that some particular scientific community acknowledges for a time as supplying the foundation for its further practice.

Science, as we know it, is based on certain definite beliefs about the world, and these beliefs have their origin in the theology of Christian Europe. The common worldview of any society is usually taken for granted by people within that society as the natural way of seeing the world. It becomes a matter of commonsense. It is not usually tested critically, or thought to need such testing. Consequently we may accept and live by a worldview belief that is inconsistent with our Christian confession without being aware of the inconsistency.

It is the aim of this study to identify the beliefs of our current scientific tradition and to arrive at normativity in empirical science according to the Biblical worldview. The approach is to outline briefly the scientific method and science as a human activity in historical perspective. If Christ is Lord of all creation, he is Lord also of the norms of human cultural and social life. To identify conditions determined by the outcomes of our investigations of the law governing creation, and to arrive at the normative functions of the investigated creation, sections on Christain faith and science, our ability to predict and life’s irreducible structure have been included.

2. The scientific method and technology

A central characteristic of the scientific method is abstraction. Consider for instance the projectile motion. To describe this motion of bodies of mass in a gravitational field, the world is reduced to two dimensions. Furthermore, the body of mass is reduced spatially to a point. The gravitational field is considered as uniform, and the interaction with the surrounding air is ignored. Therefore, the only interaction considered is between the mass point and the gravitational field in a two-dimensional plane. At this point students in an introductory physics course are learned to separate mentally (abstracting) the horizontal component of the motion from the vertical component. Once these two abstracted components of motion are understood conceptually and expressed as two algebraic equations, they are combined, both conceptually and algebraic. The result is the two-dimensional equation, describing the parabolic motion of the projectile in an idealized world.

This method was first articulated by Descartes in his Discourse on Method, and guided Western Science for centuries. His advice was to divide a problem into as many parts as possible, to think carefully from the most elementary and to solve the problem from as many different angles as possible, thus ensuring that nothing is left unconsidered. This method is powerful and reliable, and has brought us from alchemy to quantum field theory of today.

Science may be defined as “an activity in which human beings seek theoretical knowledge about creation”. The emphasis is on how creation behaves, as precisely as we can record by experimenting. It is the discovery of the law-structured creation of which we read in Psalm 19. It is a seeking after knowledge of nature.

This law-structured knowledge of an abstract world, created by the empirical sciences, depends on inductive and deductive logic. The abstract knowledge of science is realized in the real world by technology through engineering design. Technological problems are multifaceted problems, the solution of which must take the multifaceted and integrated character of the real world into account. Technology must, therefore, be holistic (Adams, 1997:345).

Holism in technology, in engineering design, means considering all aspects of the design problem. A pluralist ontology is required if one is to approach engineering design holistic (Adams, 1997:353). One of the hallmarks of Dutch neo-Calvinist philosophy has been a pluralistic ontology whereby fifteen irreducible modes of being are identified and arranged hierarchically (Kalsbeek, 1975: 84), from less to more complex modes so that each aspect of reality builds on those below it.

The emphasis of technology is on developing the natural creation, the real world, for practical ends and purposes. Technology, as engineering design is, in effect, a human cultural activity that involves interplay between theory, experiment and imagination, with scientific knowledge and satisfaction of humankind’s needs at its roots. This kind of activity is normed, that is, there are “good” and “bad” designs.

Science is not simply a matter of observing facts (Stoker, 1976, Geertsema, 1992, Stafleu, 1998,). Every scientific theory expresses a worldview. Philosophical preconceptions determine where facts are sought, how experiments are designed and which conclusions are drawn from them. It is only by grasping the worldview traditions, that have shaped the development of science, that normative functions can be identified.

3. Science as a human activity

(a)The religious ground motive

A human enterprise, such as the present space era, has not come into being on its own. Powerful rockets are needed to carry the space ship into space against the force of gravity. Such an enterprise is driven by human motives and forces. Man wants to achieve something. The technologies of the space era are part of our present cultural activities, and are embodied in our aviation, information technologies, medical and geological sciences, and all other sciences and technologies.

The fundamental driving force towards cultural achievement is, according to Dooyeweerd, the so-called religious ground motive. Any religion has a ground motive, which provides the deepest motive for driving cultural and spiritual developments, also for driving mental attitudes.

(b)The dialectic Greek philosophy

The mental attitude of ancient Greek philosophy was guided by a dialectic form-matter ground motive in order to explain observable variations in the world (Dooyeweerd, 1949:10). Mental attitudes were governed by dialectic tension in the Greek observations of nature (‘physis’), in which structurally shaped forms (eg. of man, animals, seed, vegetation and trees) emerge and eventually decay to amorphous matter.

Also Aristotle’s concept of space was determined by the dialectic way of thinking. He subdivided space into earthly and celestial worlds. In the earthly space all things strive towards a condition of rest. All growth and motion come eventually to rest, and decay. Contrary to earthly space, all motion in the celestial space is everlasting and circular. Since the dialectic way of thinking wants to synthesize these opposing spatial features, Aristotle proposed a third space above the celestial, in which the gods reside. These gods would control earthly events from the third space through celestial movements.

According to Dooyeweerd (1959:15), the ground motive of all natural religions lies in the concept of time of the primitive peoples. For them time is a deification of the formless stream of life with a circular course, that always returns to itself. Through this circular life stream, new forms appear continuously from earth, attain maturity and decompose eventually to formless matter.

(c)The Biblical world view

The God of Israel differs radical from the Greek gods. For the Greeks, matter was everlasting and provided the fundamental driving force, the first (fundamental) cause for earthly events. Aristotle saw the world as an organism, which let things happen by purpose (teleology). Whereas the Greeks believed that their gods originated from earth, the God of Israel is not part of His creation, but transcendental to it. The God of Israel is eternal, but not His creation. The earth has no driving force of its own except from God’s Providence. Nature may be investigated without fear, because there are no magic forces immanent in the earth. For the Israeli prophets and, lateron, the Christians, the course of time is linear and not circular - Creation, the Fall, birth of Christ, crucifixion, and Ascension happened only once. Hence the belief in a linear course of time.

(d)Newtonian tradition

Galileo (1564-1642) laid the foundation of mechanics in his study of motion, emphasizing the importance of the concept of acceleration. It remained for Newton (1642-1727) to establish mechanics as a precise science by stating his three laws of motion. These laws elevated mechanics from a semi-empirical, semi-mathematical science to a complete mathematical discipline, as rigorous as geometry. These laws of motion were the impetus for the development of modern science since early 1700.

Modern science (the era since Newton) is far more than the random gathering of observable data. It also encompasses the drive to discover causal relationships among the individual bits of data as we observe the universe all around us. Modern scientists have the desire to know the basic interrelationships that govern all observable phenomena. They seek to explain phenomena from these interrelationships, by accepting these interrelationships as laws of nature. The methodology of modern science is first to define an event in terms of the most elementary phenomenon that can occur. To this end idealized concepts such as “point particle” (a bit of matter that has substance but no dimensions) are introduced. Clearly, a point particle can have no real existence, but it is useful in our intellectual pursuit of the understanding of the nature of an event, which is now defined as the coincidence of a point particle with a given point of space at a given time. Here new concepts have been introduced: “point of space” and “at a given time”.

(e)Measurement replaces definition

Not all the concepts, that enter into the laws of Physics, are defined. In formulating laws of nature, the physicist introduces as few undefined concepts as possible to build his law. Though there are undefinable basic concepts in physics theory, the physicist uses and works with them only if he can introduce an operational way of measuring them. Then measurement replaces definition.

The basic physical elements that enter into the description of an event are space and time. The extent of space is related to the distances between events and their relative orientations. Since we cannot define space in terms of simpler entities, we accept it as one of our basic undefinables and describe how it is measured. The measurement of distance between two events replaces then the definition of “point of space”, in which each event happens. Just as we cannot define space, we cannot define time. Instead, we describe a time-measuring operation that gives us a number as the temporal interval between two events. (Motz Weaver, 1989).

(f) The measurement operation

The measurement operation consists of laying off a unit of length (eg. the meter) along a straight line connecting the two events. A straight line is defined as the shortest distance between two points. This definition has meaning only if the geometry of space is known. In Newton’s time only Euclidean geometry was known. By Euclidean geometry we mean the set of Euclid’s basic axioms and all geometrical theorems that can be deduced from these axioms. In this geometry it is deduced that the sum of the three angles of a triangle must be equal to 1800 and that the circumference of a circle must equal 2 times the radius. However, one can never demonstrate by measurements of angles of triangles or circumferences of circles that Euclidean geometry correctly describes our space.

Furthermore, distances in the empirical world ranch at any moment from the extremely tiny (eg. spacing between neutrons and protons in the atomic nucleus) to the astronomical distances (between galaxies). One may ask whether one can attach the same geometrical meaning to all the distances in this vast range of orders of magnitude. This question is important since the direct operation of laying off a unit of length to obtain a distance is applicable only to distances within our reach, and certainly does not apply to extremely tiny and to cosmological distances.

(g) Uniformitarianism

According to the uniformity principle the geometry, the composition of matter and the laws of nature are the same throughout space (Davies, 1993:197). This principle was accepted by Newton when he disclaimed Aristotle’s subdivision of space into earthly and celestial. Newton accepted one infinite absolute space, in which time and space existed independent from each other and from the observer. Einstein, on the other hand, interrelated space and time in his theory of relativity by merging three-dimensional space and one-dimensional time into a four-dimensional space-time continuum. Now observation depends on the frame of reference of the observer.

Uniformitarianism is usually expressed as ‘the future will resemble the past’. This is taken to mean that what has happened once will happen again if the circumstances are sufficiently similar. Geological dating, for instance, is based on the notion that one could estimate ages of geological features by determining rates of the processes responsible for such features, and then assuming the rates to be constant over time. (Lunine, 1999:75). The first exponent of applying uniformitarianism to geological processes was Herodotus (480-425 B.C.). He observed that the NileRiverValley was subject to annual cycles of flooding. He came to the important conclusion that the Nile Delta was in fact a series of sediments built up in successive floods. He was able to conclude that the Nile Delta had taken many thousands of years to build up. Observations in nature are made by man over a relatively short span of life and create, consequently, the impression that, geologically speaking, the physical circumstances have stayed the same over millions of years. This led to the inductive inference that processes in nature may be regarded as continuous for geological age determinations.

(h) Darwin’s view of nature

Though Darwin’s view of nature was mechanistic, it was quite different from the mechanistic philosophy of classical Physics. “In earlier centuries, scientists had seen no conflict between a mechanistic picture of nature and belief in God. Nature was regarded as a delicately adjusted machine, a stationary engine whose mechanism implied the existence of a purposeful engineer, a beneficent first cause or Author of the Universe” (Pearcey and Thaxton, 1994:116).

With Darwin the machine became self-generating and self-operating (Davies, 1993:203). Then the historian Carl Becker (1932:162) explains: “nature was conceived not as a finished machine but as an unfinished process, a mechanistic process, indeed, but one generating its own power” – eliminating the need for an external engineer or creator. By the end of the nineteenth century, mechanistic philosophy had become radically materialistic and reductionistic. It pictures things as automata in a world governed by rigid deterministic laws.

(i) The concept of the physical field

According to Newton, theory is hypothetic and contingent in nature, and is justified by experiment and observation. Mathematical theory is considered essential to interrelate measured entities. The success of the Newtonian method in mechanics stimulated development in other branches of the physical sciences, such as optics, heat, electricity and magnetism, and electrochemistry. Whereas Newtonian mechanics operated with the concepts of mass, force and energy, the physical concept of field was introduced about 1850 in electromagnetism. In the Newtonian tradition the physical field was defined as an operational concept with only imaginative meaning in reality. A field was described mathematically, unrelated to matter. The field concept brought forward a unifying theory for the different branches of Physics (Stafleu, 1998).

Early in the twentieth century it was obvious that the atom cannot be described by Newtonian mechanics. The concept of forces acting on material particles had to be replaced by fields. The physical reality is now described by field dynamics instead of material dynamics, using quantum field theory with particles the quanta of fields.

(j) Science of the twentieth century

Einstein merged three-dimensional space and one-dimensional time into a four-dimensional space-time manifold, as demanded by both his special (1905) and general (1915) theories of relativity. An acceptable physical theory must be “relativistic invariant”, in that it must conform to certain constraints imposed by the theory of relativity. This implies that all laws of nature must be such that they are the same for all observers, regardless of their frames of reference (their states of motion). This requirement applies also to the quantum theory as it does to all other theories. The quantum theory emerged after the discovery of Planck in 1900 in that energy changes in a discrete way and not continuous. These theories had a great impact on physics and on our thinking in general.

Quantum theory has been spectacular successful. It has made possible major developments in practical hardware, including the electron microscope, the laser and the transistor. It has been confirmed to an extremely high degree of accuracy. It is often cited as the most successful theory ever produced. But what is the nature of the reality described by quantum theory? What ontology does it imply? These are unanswered questions regarding its philosophical meaning. There are varying interpretations of quantum physics, of which parts may be taken as fundamental and empiristic and other parts as mathematical formalism with no counterpart in the real world.

One of the interpretations of quantum mechanics led to the many-worlds view when answers to the following questions were sought: Why should our experiments enjoy the privileged status of being capable of creating reality? And why should our acts of observation have the power to create just one from many possible outcomes? In denying that the act of observation has any such power, the many-worlds view came forward, one world for each possible outcome. This many-worlds view is incorporated into speculations on the origin of the universe. In the fraction of a microsecond after the Big Bang, so the theory goes, when the constituents of matter were first forming, events took place on the quantum level.