PHILOSOPHY OF SCIENCE AN INTRODUCTION
© Copyright 1995, 2005, 2016, 2019 by Thomas J. Hickey
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This book sets forth the elementary principles of the contemporary pragmatist (a.k.a. the New Pragmatist or neopragmatist) philosophy of science including its underlying neopragmatist philosophy of language, and it briefly describes the new and emerging area of computational philosophy of science. Computational philosophy of science is not something outside of philosophy of science; it is twenty-first century philosophy of science. Obviously this brief introduction can make no claim to completeness.
My previous books include Introduction to Metascience: An Information Science Approach to Methodology of Scientific Research (1976), History of Twentieth-Century Philosophy of Science (1995), and the e-book Twentieth-Century Philosophy of Science: A History (2016). This introductory book is also available as an e-book. The e-books are also available in a free Internet web site www.philsci.com, which offers the books as free pdf downloads.
In his magisterial Types of Economic Theory Wesley Clair Mitchell, Columbia University American Institutionalist economist and founder of the prestigious National Bureau of Economic Research wrote that the process that constitutes the development of the social sciences is an incessant interaction between logically arranged ideas and chronologically arranged events. Since modern science is an evolving cultural institution, this memorable Institutionalist refrain can be adapted for philosophy of science: The process that constitutes the development of philosophy of basic science is an episodic interaction between analyses in philosophy and developments in science. Modern philosophy was formed in response to the historic Scientific Revolution commencing with Copernicus and completed by Newton. In fact all philosophy of science can be called a footnote to Newton.
Since the demise of positivism, there has been an institutional change in philosophy of science. The institution-changing developmental episodes that produced the contemporary pragmatist philosophy of science are the scientific revolutions created by Einstein and especially by Heisenberg. These revolutions produced basic revisions in philosophy of language as well as in physics. In fact contemporary pragmatist philosophy of science could be called a footnote to Heisenberg.
Quine said that there are two kinds of philosophers: Those who write philosophy and those who write history of philosophy. Most books on philosophy of science treat philosophy of science in an historical perspective. This book is not a history of philosophy of science; it is a work in philosophy – a coherent and synthetic examination of the contemporary ascendant pragmatist philosophy of science. Both during and before the positivist era the purpose of philosophy of science was typically viewed in terms of justifying the superior epistemic status of empirical science.
Today few philosophers of science perceive any imperative for such justification of science, and often dismiss such efforts as merely pedantic exercises. Now the aim of philosophy of science is seen to characterize the practices that have made the empirical sciences so unquestionably successful. As stated below in the first chapter of this book: “The aim of contemporary pragmatist philosophy of science is to discover principles that explain successful practices of basic-science research, in order to advance contemporary science by application of the principles” (Section 1.01).
This book has benefited greatly from my more than thirty years of practical research experience as an econometrician working in both business and government. This practical work has included application of my METAMODEL mechanized discovery system for most of my career. I have therefore concluded that the philosopher of science must get his hands dirty with data, in order to have a realistic appreciation of empirical science.
And I add that contrary to my early expectations I can now say in retrospect that the contemporary pragmatist philosophy has been more enabling for my successful practical economic research than my graduate-level textbook lessons in economics. I find economic theory has too much imputed fantasy and too little investigative empiricism. I hope this short introductory book benefits other working scientists as well as academic philosophers of science.
I expect that the reader may have the same difficulty assimilating this introductory book that I have had in writing it. The contemporary pragmatist philosophy set forth herein is an integrated system of inter-related concepts that are mutually defined by the context constituting the metatheory. Its exposition therefore cannot simply be linear, because any beginning presupposes things that follow. My attempt to cope with this circularity has been to approach the system in a sequence of levels of presentation. This treatment of circularity has occasioned some repetition in the exposition and some overlap among the chapters, in order to provide context for understanding. I have made the table of contents more detailed than the brief outline below.
Chapter 1 is definitional: it sets forth several strategic concepts used throughout the book.
Chapter 2 is didactic: it contrasts the basic features of neopragmatism with comparable ideas in the older romantic and positivist philosophies.
Chapter 3 is essential:it describes the new contemporary pragmatist (or neopragmatist) philosophy of language that is central to and distinctive of the neopragmatist philosophy of science.
Chapter 4 is synthesizing:it describes the four functional topics that are characteristic of basic-research science in terms of the new philosophy of language.
A reviewer of an earlier edition called this book a “manifesto”. The book is explicitly addressed to academic philosophers and their students, and it does indeed advocate both the contemporary pragmatist philosophy of science and the new specialty called computational philosophy of science. Thus it has an explicit agenda and is indeed a manifesto. It furthermore proposes to benefit many academics in the philosophically retarded social sciences.
Thomas J. Hickey, Econometrician
River Forest, IL 60305
1 September 2019
CHAPTER 1. Overview
Both successful science and contemporary philosophy of science are pragmatic. In science, as in life, realistic pragmatism is what works successfully. This introductory book is a concise synthesis of the elementary principles of the contemporary pragmatist (a.k.a. neopragmatist) philosophy of science, the philosophy that the twentieth century has bequeathed to the twenty-first century. This first chapter defines some elementary concepts.
1.01 Aim of Philosophy of Science
The aim of contemporary pragmatist philosophy of science is to discover principles that explain successful practices of basic-science research, in order to advance contemporary science by application of the principles.
The principles are set forth as a metatheory, which is sketched in this book. Basic science creates new language: new theories, new laws and new explanations. Applied science uses scientific explanations to change the real world, e.g., new technologies, new social policies and new medical therapies. Philosophy of science pertains to basic-science practices and language. However, applied science in the real world offers a positive feedback to basic science. Academics often have their pet ideas that motivate them to reject alternative but empirically warranted laws. But successful application of the scientific law will eventually influence even the most obdurate naysayer making him a pragmatic realist in spite of himself.
1.02 Computational Philosophy of Science
Computational philosophy of science is the design, development and application of computer systems that proceduralize and mechanize productive basic-research practices in science.
Philosophers of science can no longer be content with more hackneyed recitations of the Popper-Kuhn debates of half a century ago, much less more debating ancient futile ethereal metaphysical issues such as realism vs. idealism.
Philosophy of science has taken the computational turn. Mechanized information processing (a.k.a. artificial intelligence) has permeated almost every science, and is now belatedly intruding into philosophy of science. Today computerized discovery systems facilitate investigations in philosophy of science in a new specialty called “computational philosophy of science”.
The pragmatist philosophers Charles Sanders Peirce (1839-1914) and Norwood Russell Hanson (1924-1967) had described a nonprocedural analysis for developing theories. Peirce called this nonprocedural practice “abduction”; Hanson called it “retroduction”. Today in computational philosophy of science procedural strategies for developing new theories are coded into computer systems.
1978 Nobel-laureate economist Herbert Simon (1916-2001), a founder of artificial intelligence, called such systems “discovery systems”. In the 1970’s Hickey (1940) in his Introduction to Metascience: An Information Science Approach to Methodology of Scientific Research (1976) called the mechanized approach “metascience”. In the 1980’s philosopher of science Paul Thagard (1950) in his Computational Philosophy of Science (1988) called it “computational philosophy of science”, a phrase that is more descriptive and therefore will probably prevail.
Mechanized simulation of successful developmental episodes in the history of science is typically used to test the plausibility of discovery-system designs. But the proof of the pudding is in the eating: application of computer systems at the frontier of a science, where prediction is also production in order to propose new empirically superior theories, further tests the systems. Now philosophers of science may be expected to practice what they preach by participating in basic-science research to produce empirically adequate contributions. Contemporary application of the discovery systems gives the philosopher of science a participatory and consequential rôle in basic-science research.
1.03 Two Perspectives on Language
Philosophy of language supplies an organizing analytical framework that integrates contemporary philosophy of science. In philosophy of language philosophers have long distinguished two perspectives called “object language” and “metalanguage”.
Object language is discourse about nonlinguistic reality including domains that the particular sciences investigate as well as about the realities and experiences of ordinary everyday life.
Metalanguage is language about language, either object language or metalanguage.
Much of the discourse in philosophy of science is in the metalinguistic perspective. Important metalinguistic terms include “theory”, “law”, “test design”, “observation report” and “explanation”, all of which are pragmatic classifications of the uses of language. For example in the contemporary pragmatist philosophy a “theory” is a universally quantified hypothesis proposed for empirical testing. A “test design” is a universally quantified discourse presumed for the empirical testing of a theory in order to identify the subject of the theory independently of the theory and to describe the procedures for performing the test. The computer instructions coded in discovery systems are also metalinguistic expressions, because these systems input, process and output object language for the sciences.
1.04 Dimensions of Language
Using the metalinguistic perspective, philosophers analyze language into what Rudolf Carnap (1891-1970) called “dimensions” of language. The dimensions of interest to neopragmatist philosophers are syntax, semantics, ontology, and pragmatics.
Syntax refers to the structure of language. Syntax is arrangements of symbols such as linguistic ink marks on paper, which display structure. Examples of syntactical symbols include terms such as words and mathematical variables and the sentences and mathematical equations constructed with the terms.
Syntactical rules regulate construction of grammatical expressions such as sentences and equations out of terms, which are usually arranged by concatenation into strings.
Semantics refers to the meanings associated with syntactical symbols. Syntax without semantics is literally meaningless. Associating meanings with the symbols makes the syntax “semantically interpreted”.
Semantical rules describe the meanings associated with elementary syntactical symbols, i.e. terms. In the metalinguistic perspective belief in the truth of semantically interpreted universally quantified sentences such as the affirmation “Every crow is black” enables sentences to function as semantical rules displaying the complex meanings of the sentences’ component descriptive terms. Belief in the statement “Every crow is black” makes the phrase “black crow” redundant, thus displaying the meaning of “black” as a component part of the meaning of “crow”. The lexical entries in a unilingual dictionary are an inventory of semantical rules for a language. This is not “rocket science”, but there are philosophers who prefer obscurantism and refuse to acknowledge componential semantics.
Ontology refers to the aspects of reality described by semantically interpreted sentences believed to be true, especially belief due to experience or to systematic empirical testing. This is the thesis of ontological relativity. Ontology is typically of greater interest to philosophers than to linguists.
Semantics is knowledge of reality, while ontology is reality as known, i.e. semantics is the perspectivist signification of reality, and ontology is the aspects of reality signified by semantics. Ontology is the aspect of mind-independent reality that is cognitively captured with the perspective revealed by semantics.
Not all discourses are equally realistic; the semantics and ontologies of discourses are as realistic as they are empirically adequate. Since all semantics is relativized and ultimately comes from sense stimuli, there is no semantically interpreted syntax of language that is utterly devoid of any associated ontology. If all past falsified explanations were simply unrealistic, then so too are all currently accepted explanations and all future ones, which are destined to be falsified in due course. Better to acknowledge in all explanations the degree of realism and truth that they have to offer. Scientists recognize that they investigate reality and are motivated to do so. Few would have taken up their basic-research careers had they thought they were merely constructing fictions with their theories or fabricating semantically vacuous instrumentalist discourses.
Pragmatics in philosophy of science refers to how scientists use language, namely to create and to test theories, and thereby to develop scientific laws used in test designs and in scientific explanations. The pragmatic dimension includes both the semantic and syntactical dimensions, such that the dimensions of language are telescoped:
1.05 Classification of Functional Topics
Basic-science research practices can be classified into four essential functions performed in basic research. They are:
1. Aim of Basic Science
The institutionalized aim of basic science is the culturally shared aim that regulates development of explanations, which are the final products of basic-scientific research. The institutionalized views and values of science have evolved considerably over the last several centuries, and will continue to evolve episodically in unforeseeable ways with future advancements of science.
Discovery refers to the processes of constructing new theories. Pragmatists define theory language pragmatically, i.e., functionally.
A theory is a universally quantified hypothesis that is proposed for empirical testing.
Today scientific discovery is facilitated by artificial-intelligence discovery systems.
Criticism refers to the decision criteria for the evaluation of theories. Pragmatists accept only the empirical criterion. The pragmatics of theory language is empirical testing and it uses modus tollens conditional deductive argument form, which includes universally quantified statements and/or equations that can be schematized in nontruth-functional conditional form and that are proposed hypotheses. The scientific theory in the deduction is a set of one or several universally quantified related statements expressible jointly in conditional form.
Some linguists might regard the nontruth-functional conditional schema to be the fundamental “deep structure” of the language of basic science, while they regard the formulations of theory actually used by scientists as “surface structure”.
A test design is a universally quantified discourse that is presumed for empirical testing a theory, in order independently to identify the subject of the theory and to describe the procedures for performing the test.
A scientific law is a former theory that has been tested with a nonfalsifying outcome.
An explanation is language that describes the occurrence of individual events and conditions that are caused by the occurrence of other described individual events and conditions according to law statements.
Explanation in science uses modus ponens conditional deductive argument form, which includes universally quantified related statements and/or equations that can be schematized in nontruth-functional conditional form and that are scientific laws. A scientific law is a former theory that has been tested with a nonfalsifying outcome. Whenever possible the explanation is predictive of future events or of evidence of past events.
As with criticism, so too for explanation the nontruth-functional conditional schema may be regarded as the fundamental “deep structure” of the language of basic science, while the formulations of theory actually used by scientists may be regarded as “surface structure”.
1.06 Classification of Modern Philosophies
Twentieth-century philosophies of science may be classified into three generic types. They are romanticism, positivism and pragmatism. Romanticism is a philosophy for social and cultural sciences. Positivism is a philosophy for all sciences and it originated in reflection on Newtonian physics. Contemporary pragmatism is a philosophy for all sciences, and it originated in reflection on quantum physics.
Each generic type has many representative authors advocating philosophies expressing similar concepts for such metalinguistic terms as “theory”, “law” and “explanation”. Philosophies within each generic classification have their differences, but they are much more similar to each other than to those in either of the two other types. The relation between the philosophies and the four functional topics can be cross-referenced as follows:
Aim of Science
Chapter 2. Modern Philosophies
This chapter sketches the three generic types of twentieth-century philosophy of science in terms of the four functions.
Philosophy of language will be taken up in Chapter 3. Then all these elements will be integrated in a detailed discussion of the four functional topics in Chapter 4.
Romanticism has effectively no representation in the natural sciences today, but it is still widely represented in the social sciences including economics and sociology. It has its roots in the eighteenth-century German idealist philosophers including notably Immanuel Kant (1770-1831), progenitor of romanticism, and especially Georg Hegel (1724-1804) with the latter’s emphasis on ideas in social culture. The idealist philosophies are of purely antiquarian interest to most philosophers of science today.
Romantics have historically defaulted to the positivist philosophy for the natural sciences, but they reject using the positivist philosophy for the social sciences. Romantics maintain that there is a fundamental difference between sciences of nature and sciences of culture.
Aim of science
For romantics the aim of the social sciences is an investigation of culture that yields an “interpretative understanding” of “human action”, by which is meant explanation of social interactions in terms of intersubjective mental states, i.e., shared ideas and motives, views and values including the economists’ rationality postulates, that are culturally shared by members of social groups.
This concept of the aim of science and of explanation is a “foundational agenda”, because it requires reduction of the social sciences to a social-psychology foundation, i.e., description of observed social behavior by reference to intersubjective social-psychological mental states.
For romantics the creation of “theory” in social science may originate either:
(1) in the social scientist’s introspective reflection on his own ideas and motivations originating in his actual or imaginary personal experiences, which ideas and motives are then imputed to the social members he is investigating, or
(2) in empirical survey research reporting social members’ overtly expressed verbally intersubjective ideas and motivations.
Romantics say “social theory” is language describing intersubjective mental states, notably culturally shared ideas and motivations, which are deemed the causes of “human action”. Some romantics call the imputed motives based in introspective reflection “substantive reasoning” or “interpretative understanding”. But all romantic social scientists deny that social theory can be developed by data analysis exclusively or by observation of overt behavior alone. Romantics thus oppose their view of the aim of science to that of the positivists’ such as the sociologist George Lundberg (1933) and the behavioristic psychologist B.F. Skinner (1904-1990). Romantics say that they explain consciously purposeful and motivated “human action”, while behaviorists say they explain publicly observable “human behavior”.
For romantics the criterion for criticism is “convincing interpretative understanding” that “makes substantive sense” of conscious motivations, which are deemed to be the underlying “causal mechanisms” of observed “human action”.
Causality is an ontological concept, and nearly all romantics impose their mentalistic ontology as the criterion for criticism, while making empirical or statistical analyses at most optional or supplementary.
Furthermore many romantic social scientists require as a criterion that a social theory must be recognizable in the particular investigator’s own introspectively known intersubjective personal experience. In Max Weber’s (1864-1920) terms this is called verstehen. It is the thesis that empathetic insight is a necessary and valuable tool in the study of human action, which is without counterpart in the natural sciences. It effectively makes all sociology what has been called “folk sociology”.
Romantics maintain that only “theory”, i.e., language describing intersubjective ideas and motives, can “explain” conscious purposeful human action.
Motives are the “mechanisms” referenced in “causal” explanations, which are also called “theoretical” explanations. Observed regularities are deemed incapable of “explaining”, even if they enable correct predictions.
Some formerly romantic social scientists such as the institutionalist economist Wesley C. Mitchell (1874-1948) and the functionalist sociologist Robert K. Merton (1910-2003) have instead chosen to focus on objective outcomes rather than intersubjective motives. This focus enables the testability and thus the scientific status of sociology. But the focus on objective outcomes still represents a minority view in academic social science.
Since the later twentieth century positivism has been relegated to the dustbin of history. Its origins are in the eighteenth-century British empiricist philosophers including notably David Hume (1711-1776). But not until the late nineteenth century did positivism get its name from the French philosopher Auguste Comte (1798-1857), who also founded sociology.
The “neopositivists” were the last incarnation of positivism. They attempted to apply the symbolic logic fabricated by Bertrand Russell (1872-1970) and Alfred Whitehead (1861-1947) early in the twentieth century, because they had mistakenly fantasized that the Russellian truth-functional symbolic logic can serve philosophy, as mathematics has served physics. They are therefore also called “logical positivists”.
Contrary to romantics, positivists believe that all sciences including the social sciences share the same philosophy of science. They therefore reject the romantics’ dichotomy of sciences of nature and sciences of culture.
The positivists’ ideas about all four of the functional topics in philosophy of science were influenced by their reflections upon Newtonian physics.
Aim of science
For positivists the aim of science is to produce explanations having objectivity grounded in “observation language”, which by its nature describes observed phenomena.
Their concept of the aim of science is thus also called a “foundational agenda”, although the required foundation is quite different from that of the romantics.
Positivists believed that empirical laws are inferentially discovered by inductive generalization based on repeated observations. They define empirical laws as universally quantified statements containing only “observation terms” describing observable entities or phenomena.
Early positivists such as Ernst Mach (1826-1916) recognized only empirical laws for valid scientific explanations. But after Einstein’s achievements neopositivists such as Rudolf Carnap (1836-1970) recognized hypothetical theories for valid scientific explanations, if the theories could be linguistically related to language used to report the relevant observations. Unlike empirical laws, theories are not produced by induction from repeated singular observations.
Neopositivists believed that theories are discovered by creative imagination, but they left unexplained the creative process of developing theories. They define theories as universally quantified statements containing any “theoretical terms”, i.e., terms not describing observable entities or phenomena.
Positivists’ criterion for criticism is publicly accessible observation expressed in language containing only “observation terms”, which are terms that describe only observable entities or phenomena.
The later positivists or neopositivists maintain that theories are indirectly and tentatively warranted by empirical laws, when the valid laws can be logically derived from the theories.
Like Hume they deny that either laws or theories can be permanently validated empirically, but they require that the general laws be founded in observation language as a condition for the objectivity needed for valid science. And they maintain that particularly quantified observation statements describing singular events are incorrigible and beyond revision.
All positivists reject the romantics’ verstehen thesis of criticism. They argue that empathy is not a reliable tool, and that the methods of obtaining knowledge in the social sciences are the same as those used in the physical sciences. They complain that subjective verstehen may easily involve erroneous imputation of the idiosyncrasies of the observer’s experiences or fantasies to the subjects of inquiry.
Positivists and specifically Carl Hempel (1905-1997) and Paul Oppenheim (1885-1977) in their “Logic of Explanation” in the journal Philosophy of Science (1948) advocate the “covering-law” schema for explanation.
According to the “covering-law” schema for explanation, statements describing observable individual events are explained if they are derived deductively from other observation-language statements describing observable individual events together with “covering”, i.e., universally quantified empirical laws.
This concept of explanation has also been called the “deductive-nomological model”.
The neopositivists also maintained that theories explain laws, when the theories are premises from which the empirical laws are deductively derived as theorems. The deduction is enabled by the mediation of “correspondence rules” also called “bridge principles”. Correspondence rules are sentences that relate the theoretical terms in an explaining theory to the observation terms in the explained empirical laws.
We are now said to be in a “postpositivist’ era in the history of Western philosophy, but this term merely says that positivism has been relegated to history; it says nothing of what has replaced it. What has emerged is a new coherent master narrative appropriately called “contemporary pragmatism” or “realistic neopragmatism”, which was occasioned by reflection on quantum theory, and is currently the ascendant philosophy in American academia. Contemporary pragmatism is a general philosophy for all empirical sciences, both social and natural sciences.
Pragmatism has earlier versions in the classical pragmatists, notably those of Charles Peirce, William James (1842-1910) and John Dewey (1859-1952). Some theses in classical pragmatism such as the importance of belief have been carried forward into the new. In contemporary pragmatism belief is strategic, because it controls relativized semantics, which signifies and thus reveals a correspondingly relativized ontology that is realistic to the degree that a belief is empirically adequate. Especially important is Dewey’s emphasis on participation and his pragmatic thesis that the logical distinctions and methods of scientific inquiry develop out of scientists’ successful problem-solving processes.
The provenance of the contemporary realistic pragmatist philosophy of science is 1932 Nobel-laureate physicist Werner Heisenberg’s (1901-1976) reflections on the language in his revolutionary quantum theory in microphysics. There have been various alternative semantics and thus ontologies proposed for the quantum theory. Most physicists today have accepted one that has ambiguously been called the “Copenhagen interpretation”.
There are two versions of the Copenhagen interpretation. Contrary to the alternative “hidden variables” view of David Bohm (1917-1992), both Copenhagen versions assert a thesis called “duality”. The duality thesis is that the wave and particle manifestations of the electron are two aspects of the same entity, as Heisenberg says in his Physical Principles of the Quantum Theory (1930), rather than two separate entities, as Bohm says.
1922 Nobel-laureate Niels Bohr (1885-1962), founder of the Copenhagen Institute for Physics, proposed a version called “complementarity”. His version says that the mathematical equations of quantum theory must be viewed instrumentally instead of descriptively, because only ordinary discourse and its refinement in the language of classical physics are able to describe physical reality. Instrumentalism is the doctrine that scientific theories are not descriptions of reality, but are meaningless yet useful linguistic instruments that enable correct predictions.
The quantum theory says that the electron has both wave and particle properties, but in classical physics the semantics of the terms “wave” and “particle” are mutually exclusive – a wave is spread out in space while a particle is a concentrated point. Therefore Bohr maintained that description of the electron’s duality as both “wave” and “particle” is an empirically indispensable semantic antilogy that he called “complementarity”.
Heisenberg, a colleague of Bohr at the Copenhagen Institute, proposed his alternative version of the Copenhagen interpretation. His version also contains the idea of the wave-particle duality, but he said that the mathematical expression of the quantum theory is realistic and descriptive rather than merely instrumental. And since the equations describing both the wave and particle properties of the electron are mathematically consistent, he disliked Bohr’s complementarity antilogy. Years later Yale University’s Hanson, an advocate of the Copenhagen physics, said that Bohr maintained a “naïve epistemology”.
Duality is a thesis in physics while complementarity is a thesis in philosophy of language. These two versions of the Copenhagen interpretation differ not in their physics, but in their philosophy of language. Bohr’s philosophy is called a “naturalistic” view of semantics, which requires what in his Atomic Physics and the Description of Nature (1934) he called “forms of perception”. Heisenberg’s philosophy is called an “artifactual” or a “conventionalist” view of semantics, in which the equations of the quantum theory supply the linguistic context, which defines the concepts that the physicist uses for observation.
1921 Nobel-laureate physicist Albert Einstein (1879-1955) had influenced Heisenberg’s philosophy of language, which has later been incorporated into the contemporary pragmatist philosophy of language. And consistent with his relativized semantics Heisenberg effectively practiced ontological relativity and maintained that the quantum reality exists as “potentia” prior to determination to a wave or particle by execution of a measurement operation. For Heisenberg indeterminacy is real.
The term “complementarity” has since acquired some conventionality to signify duality, and is now ambiguous as to the issue between Bohr and Heisenberg, since physicists typically disregard the linguistic issue.
For more about Heisenberg and quantum theory the reader is referred to BOOKs II and IV at the free web site www.philsci.com or in the e-book Twentieth-Century Philosophy of Science: A History, which is available from most Internet booksellers.
The distinctive linguistic philosophy of Einstein and especially Heisenberg as incorporated into the contemporary pragmatist philosophy of science can be summarized in three theses, which may be taken as basic principles in contemporary pragmatism:
Relativized semantics is meanings defined by the linguistic context consisting of universally quantified statements believed to be true.
The seminal work is “Quantum Mechanics and a Talk with Einstein (1925-1926)” in Heisenberg’s Physics and Beyond (1971). There Heisenberg relates that in April 1925, when he presented his matrix-mechanics quantum physics to the prestigious Physics Colloquium at the University of Berlin, Einstein, who was in the assembly, afterward invited Heisenberg to chat in his home that evening. In their conversation Einstein said that he no longer accepts the positivist view of observation including such positivist ideas as operational definitions. Instead he issued the aphorism: “the theory decides what the physicist can observe”.
The event was historic. Einstein’s aphorism about observation contradicts the fundamental positivist thesis that there is a natural dichotomous separation between the semantics of observation language and that of theory language. Positivists believed that the objectivity of science requires that the vocabulary and semantics used for incorrigible observation must be uncontaminated by the vocabulary and semantics of speculative and provisional theory.
In the next Chapter titled “Fresh Fields (1926-1927)” in the same book Heisenberg reports that Einstein’s 1925 discussion with him in Berlin had later occasioned his own reconsideration of observation. Heisenberg recognized that classical Newtonian physical theory had led him to conceptualize the observed track of the electron as continuous in the cloud chamber – an instrument for microphysical observation developed by 1927 Nobel-laureate C.T.R. Wilson (1869-1961) – and therefore to misconceive the electron as simultaneously having a definite position and momentum like all Newtonian bodies in motion.
Recalling Einstein’s aphorism that the theory decides what the physicist can observe, Heisenberg reconsidered what is observed in the cloud chamber. He rephrased his question about the electron tracks in the cloud chamber using the concepts of the new quantum theory instead of those of the classical Newtonian theory. He therefore reports that he asked himself: Can the quantum mechanics represent the fact that an electron finds itself approximately in a given place and that it moves approximately at a given momentum? In answer to this newly formulated question he found that these approximations can be represented mathematically. He reports that he then developed this mathematical representation, which he called the “uncertainty relations”, the historic contribution for which he received the Nobel Prize in 1932.
Later Hanson expressed Einstein’s aphorism that the theory decides what the physicist can observe by saying observation is “theory-laden” and likewise Popper (1902-1994) by saying it is “theory-impregnated”. Thus for pragmatists the semantics of all descriptive terms is determined by the linguistic context consisting of universally quantified statements believed to be true.
In his Against Method (1975, Ch. 2-3) Paul Feyerabend (1924-1994) also recognized employment of relativized semantics to create new observation language for discovery, and he called the practice “counterinduction”. To understand counterinduction, it is necessary to understand the pragmatic concept of “theory”: theories are universally quantified statements that are proposed for testing. Feyerabend found that Galileo (1564-1642) had practiced counterinduction in the Dialogue Concerning the Two Chief World Systems (1632), where Galileo reinterpreted apparently falsifying observations in common experience by using the concepts from the apparently falsified heliocentric theory instead of the concepts from the prevailing geocentric theory. Likewise Heisenberg had also practiced counterinduction to reconceptualize the perceived sense stimuli observed as the electron track in the cloud chamber by using quantum concepts instead of classical Newtonian concepts, and he then developed the indeterminacy relations.
Counterinduction is using the semantics of an apparently falsified theory to revise the test-design language that had supplied the semantics of the language describing the apparently falsifying observations, and thereby to produce new language for observation.
Like Einstein, contemporary pragmatists say that the theory decides what the scientist can observe. Thus semantics is relativized in the sense that the meanings of descriptive terms used for reporting observations are not just names or labels for phenomena, but rather are formed by the context in which they occur.
More specifically in “Five Milestones of Empiricism” in his Theories and Things (1981) the neopragmatist philosopher of language Willard van Quine (1908-2000) says that the meanings of words are abstractions from the truth conditions of the sentences that contain them, and that it was this recognition of the semantic primacy of sentences that give us contextual definition.
The defining context consists of universally quantified statements that proponents believe to be true. The significance is that the acceptance of a new theory superseding an earlier one and sharing some of the same descriptive terms produces a semantical change in the descriptive terms shared by the theories and their common observation reports. The change consists of replacement of some semantical component parts in the meanings of the terms in the old theory with some parts in the meanings of the terms in the new theory.
Thus Einstein for example changed the meanings of such terms as “space” and “time”, which occur in both the Newtonian and relativity theories. And Heisenberg changed the meanings of the terms “wave” and “particle”, such that they are no longer mutually exclusive. Feyerabend calls the semantical change due to the relative nature of semantics “meaning variance”.
For more about Quine the reader is referred to BOOK III at the free web site www.philsci.com or in the e-book Twentieth-Century Philosophy of Science: A History, which is available from most Internet booksellers.