SCIENTIFIC REALISM AND INSTRUMENTALISM

INTRODUCTION

Science on its own has theories which are proven knowledge that are derived in some rigorous ways from the facts of experience acquired by observation and experiment. These theories are based on what we can experience and observe. Consequently, there are central issues or concerns in the philosophy of science that have occupied the minds of many thinkers. Chief among these issues is the debate between scientific realism and instrumentalism. These issues raise two fundamental questions and these questions are: what are the aims of science? That is, does science aim at telling us the truth about reality or it is just a navigation of reality that gives us things that make us able to interact with reality, paving way to pragmatism? How should we interpret the theories or results of science, such that the theories or principles science adopts are true or approximately true? Answers to these questions are typically classified as either realist or anti-realist (Instrumentalist).

In this essay, it is our aim to critically expose and evaluate scientific realism and instrumentalism. We shall extensively examine the views of the scientific realists alongside scientific instrumentalism under various headings, and finally, the conclusion.

CLARIFICATION OF TERMS

In order to avoid ambiguities in the course of our presentation, we shall define certain terms used in the work. These terms are scientific realism and scientific instrumentalism.

SCIENTIFIC REALISM: It is at the most general level, the view that the world described by science (perhaps ideal science) is the real world, as it is, independent of what we might take it to be. Within philosophy of science, it is often framed as an answer to the question “how the success of science is to be explained?” The debate over what the success involves centers primarily on the status of unobservable entities apparently talked about by scientific theories.[1]

SCIENTIFIC INSTRUMENTALISM: In respect of philosophy of science, scientific instrumentalism is a school of thought that describes scientific theory as useful instrument in understanding the world.  A concept or theory should be evaluated by how effectively it explains and predicts phenomena, as opposed to how accurately it describes objective reality. It is apt to note here that the word anti-realists are also referred to as instrumentalists. [2]

THE ORIGIN OF THE DEBATE ON SCIENTIFIC REALISM

The issue of scientific realism is an old issue in philosophy and has always been in existence; but it was not until the twentieth century that the debate regarding it became more prominent in the philosophy of science. The first quarter of the century was marked by a somewhat unsophisticated general realism, most memorably the critical realism of Roy Wood Sellars, formed in reaction to the rampant idealism of the nineteenth century. It was not until the 1960s, after a multifaceted attack on logical positivism, that realism was revived under the guidance of such figures as Karl Popper, Grover Maxwell, and J. J. C. Smart. At around the same time, the historically motivated work of Thomas Kuhn and Paul Feyerabend inspired new` converts to, and new versions of, anti-realism. Realist voices were not kept at bay, however, with Hilary Putnam and Richard Boyd, among others, keeping the debate alive in the seventies. In the early eighties, the independent but equally powerful critiques by Bas van Fraassen and Larry Laudan shaped old problems into new challenges for the scientific realist. The debate as it is carried out today owes much to these developments, especially those that emerged after 1960.[3]

SCIENTIFIC REALISM

Realism, at the most general level, holds that there are entities in this world that exist independently of our mind. From a scientific perspective, scientific realism means that the world studied by science really exists and has the property independently of our beliefs, and that the aim of science is to describe and explain the world including parts of it that are not directly observable. Moreover, scientific realism also means that to accept scientific theory is to think that it is at least approximately true, and that later and more successful theories are closer approximations of truth.[4]

Consequently, the term scientific realism denotes a precise position on the question of how a scientific theory is to be understood, and what scientific activity really is. Realism in the philosophy of science is basically the thesis that unobservable entities posited by empirically successful theories exist. Theoretical posits, like electrons or genes are not just useful ideas but real entities. Realism takes the explanatory and predictive success of theories to warrant an ontological commitment to the existence of the entities they posit. But it is certainly possible for theoretical posits to be useful even if the entities posited do not exist.[5]

Put differently, scientific realism is the position that scientific theory construction aims to give us a literally true story of what the world is like, and that acceptance of a scientific theory involves the belief that it is true.[6] Roughly speaking, scientific realism is the view that we should believe in the unobservable objects postulated by our best scientific theories.[7] Thus, we can by this means, infer that the naive statement on the aforementioned position would be that the picture which science gives us of the world is true, faithful in its details, and the entities postulated in science really exist.

Realism typically involves the notion of truth. For the realist, science aims at truth descriptions of what the world is really like. Put differently, scientific realism accounts for the predictive and instrumental success of science by means of the (approximate) truth or truth-likeness of scientific theories. In an informal but adequate way, truth-likeness can be defined as the conjunction of approximate truth and a high informative content.[8] A theory that correctly describes some aspect of the world and its mode of behaviour is true, while those that incorrectly describes some aspect of the world and its mode of behaviour is false.[9] Our rough understanding of the concept of knowledge holds that to know a thing is to have a Justified True Belief (JTB) about it. The theory of truth most conducive to the needs of the realist is the correspondence theory of truth.[10] This theory makes two main claims. First, a proposition is true if and only if it corresponds to the facts. Second, a proposition is false if and only if it fails to correspond to the facts.[11] What is more, to have knowledge of some aspect of the world involves the true belief that the world is in a certain state. Thus, we can express the scientific realist view that we have knowledge (including the observable and unobservable entities) of the world by saying that scientific claims about the world are true. In other words, we can represent scientific realism as the position which holds that the scientific claims about the observable and unobservable aspects of the world are true.

For an outstanding realist such as Richard Boyd, the approximate truth of scientific theories explains the instrumental reliability of scientific methods, which are theory-dependent. This reliability of methods explains in turn, in a dialectic way, the approximate truth of new theories. Many other scientific realists have supported the idea that if the theoretical entities postulated by scientific theories did not exist at all, and if these theories were not approximately true, then the success of science would be a miracle.[12]

SCIENTIFIC ANTI-REALISM

All anti-realists share a distrust of, or a skeptic view towards the realist claims. Like realism, anti-realism can be found in various forms and guises. With regard to scientific knowledge, the general anti-realist intuition is that we cannot know whether any of the claims made by scientific theories about the mind independent world are true or approximately true. As a consequence, anti-realists consider the realist claims unwarranted.[13]

            In his book “What Is This Thing Called Science”, Chalmers reiterated that the anti-realist maintains that the content of a scientific theory involves nothing more than the set of claims that can be substantiated by observation and experiment. According to him, antirealists are often called, instrumentalists. For them, theories are nothing more than useful instruments for helping us to correlate and predict the results of observation and experiment.[14] This position strongly holds to the pragmatic theory of truth. It will interest us to recall that the central insight of the pragmatic theory is that true beliefs are generally useful while false beliefs are not.[15] Thus, the validity of a scientific theory is not depended on the truthfulness of theory but on its usefulness (We shall be discussing more on instrumentalism later on). Henri Poincare (1952) as cited in Chalmers (1999) exemplified this position when he compared theories to a library catalogue. Catalogues can be appraised for their usefulness, but it would be wrong-headed to think of them as true or false.[16]

PUTNAM’S ARGUMENT AGAINST REALISM

As construed by Putnam, metaphysical realism is the view that the world is independent of the theories we come to accept as correct descriptions of the world. For him, this condenses to the metaphysical realist’s insistence that even an ideal theory (that is, one satisfying all imaginable theoretical and operational constraints, such as consistency, completeness, agreement with all observation, simplicity, beauty, et cetera) may nonetheless be false about the world.[17] Put differently, metaphysical realism is the view that our ordinary language refers to, and sometimes says true things about, a mind independent world. By mind-independence, we mean, that even if there were suddenly no human beings or other creatures to perceive tables, those that exist would still do so. In other words, the table in a room is there whether or not anyone looks at it.[18]

            Putnam further attempt to show that the world is to be independent of any particular representation or theory we have of it, it is held that we might be unable to represent the world at all. The most important consequence of metaphysical realism Putnam continues is that truth is supposed to be radically non-epistemic. According to him, we might be brain in a vat (BIV) and so the theory that is ideal from the point of view of operational utility, inner beauty and elegance, plausibility, simplicity, conservatism among others, might be false.[19] Thus, verification does not imply the truth value of a theory.

OTHER ARGUMENTS AGAINST REALISM

            One of the most important criticisms against the realist thesis is displayed by Laudan in his article "A Confutation of Convergent Realism". Sometimes it is named as the pessimistic induction, or the pessimistic meta-induction. Pessimistic induction is an attempt to prove the defense of scientific realism wrong in their claim that scientific theories are sure means of knowledge or arriving at the truth about the physical world. According to Laudan, the realist is committed in his argument to the following two theses:

(T1) If a theory is approximately true, then it will be explanatorily successful.

(T2) If a theory is explanatorily successful, then it is probably approximately true.[20]

Laudan's argument to refuse T1 is short and simple. Whereas it is self-evident that a true theory will be a successful theory, since the conclusions derived from it must be true, the logic of approximate truth does not allow for the same argument about an approximately true theory. The consequences inferred from an approximately true theory do not have to be approximately true. A theory can be approximately true, and yet all of its tested consequences could be false. So the approximate truth does not ensure the predictive success of scientific theories. Furthermore, we lack an adequate criterion for the ascription of approximate truth to a theory.[21]

Laudan substantiated his argument by means of what he called the historical gambit. These are theories which were once empirically successful and fruitful, yet were neither referential nor true, such as, the crystalline spheres of ancient and medieval astronomy and the humoral theory of medicine. Others are the effluvial theory of static electricity; catastrophist geology, with its commitment to a universal (Noachian) deluge; the phlogiston theory of chemistry; the caloric theory of heat; the vibratory theory of heat; the vital-force theory of physiology; the theory of circular inertia.[22] What is more, If Laudan theses are considered true, the realist’s explanation of the success of science flies in the face of the history of science.

HUME’S CRITIQUE ON INDUCTION

Hume’s critique of the inductive method is found in his work “An Enquiry Concerning Human Understanding”. In section two of his work, “An essay concerning human understanding”, Hume raises a question which somewhat reveals his notion of the problem of induction. The question is as follows; “The bread, which I formerly eat, nourished me; that is, a body of such sensible qualities was, at that time, endued with such secret powers: But does it follow, that other bread must also nourish me at another time, and that like sensible qualities must always be attended with like secret powers?”[23]

            By raising this question, Hume clearly critiques the very foundation of induction itself, which for him lies on the basic assumption that “from causes which appear similar we [should] expect similar effects.”[24] That is, just because “I... found that such an object (say bread) has always been attended to with such an effect (nourishing)... I foresee or infer that other objects with similar appearance, will be attended to with similar effects”[25] As it were, from past experience(s) the future can be foreseen and predicted, since by inductive inference the future will always resemble the past. Clearly, Hume sees the inductive method to be based on an assumption of a causal connection. A causal connection whose nature is unknown, and whose basis needs justification. This explains why Hume raises the question, what is the justification that since bread formerly nourished me then it will always nourish me? Does it follow of necessity? Simply put, is there any justification for making such inductive inferences?

            The corollary of Hume’s critique of induction is to call into question, the realist’s claim that scientific theories account for both observable and unobservable “facts” are true. As shown from his critique of induction, it is axiomatic that scientific theories may not always present the truth of the total universe.

CRITIQUE OF SCIENTIFIC REALISM

The realist thinks that, if some additional conditions are given, it is probable for truth-like theories to be predictive and instrumentally successful. These theories provide us with an approximately true knowledge about natural phenomena, which can be used in a reliable way to manipulate objects, to predict and control their behaviour, and to do things with them. Without it, prediction and control would be, if not impossible, very difficult to carry out. The anti-realists are right when they adduce that from false premises true consequences also can be derived, but it cannot be expected that we frequently draw relevant consequences able to be used in practice from false theories.[26]

This means that the realist's account should be applied to long periods in history of science, but not to every episode of success. The realist can admit, that in occasional circumstances, scientific success is due to different causes. But a lengthy and reiterated success of a theory in very different contexts is for the realist a sign that there is more than a simple empirical adequacy between theory and reality. Let us consider the following analogy. Army A has won the war against army B, and army A is more numerous, better trained, and better armed than army B. In those circumstances, the superiority of army A in number of soldiers, training, and arms is the best explanation of its victory over B, because that is what can be expected if we have no other information. It does not imply, however, that army A won all battles against army B, or that every victory of A over B has been due to these reasons. The morale of army B might have been on some occasion higher than the morale of A, so that B won a battle against A despite its inferiority. Likewise, army A could sometimes defeat B not because of its superiority, but because of the bad weather or another accidental matter.

INSTRUMENTALISM

Instrumentalism, unlike realism, holds a contrary view. For the instrumentalist, scientific theories do not describe the objective reality of the physical world, rather they are instruments designated to relate one component or set of observation with others. For this school of thought, the molecules in motion which the kinetic theory of gases made reference to is nothing but convenient fictions which will enable scientists relate and make predictions concerning manifestations of the properties of gases, which are observable. In terms of electromagnetic theory, the fields and charges are fictions which will enable science also make necessary predictions about magnets, current-carrying circuits and electrified bodies.[27]

The aim of science is to produce theories that are convenient devices or instruments for connecting one set of observable situations with another. Descriptions of the world involving observable entities do describe what the world is really like, but descriptions of systems involving theoretical concepts do not. The latter is to be understood as useful fictions facilitating our calculations. Some simple examples will illustrate the instrumentalist position. The naïve instrumentalist will admit that there really are billiard-balls in the world and that they can roll at various velocities, colliding with each other and with the sides of a billiard-table, which also really exists. Newtonian mechanics is to be regarded in this context as a calculating device, enabling the observable positions and velocities of the billiard-balls at some instance of time to be deduced from their observable positions and speeds at some different time. The forces involved in these and similar calculations (the impulsive forces due to impact, frictional forces, etc) are not to be taken as entities that really exist. They are inventions of the physicist.”[28]

The general outlook of the project of the instrumentalists is that, scientific theories are merely sets of rules which help us to connect one set of observable entity with another. Given some specific examples things like Ammeters, planets, iron filings, and light rays really exist in the world but electrons, Ptolemaic epicycles, magnetic fields and the aether need not exist. For the instrumentalists, whether besides observable things, there are other things existing in the world, which perhaps account for the behaviour of observable realities, is not the concern of the naïve instrumentalist. For them, it is not the concern of science to establish whatever may exist outside or beyond the field of observation. In other words, science provides no sure means of closing the gap between what can be observed and what cannot be observed.[29]

CRITIQUE OF INSTRUMENTALISM

The sharp distinction that instrumentalism makes between observation and theory is one issue that has not escaped the critical ratiocinative cursive of critics. Inasmuch as instrumentalists share a cautious attitude with the inductivists, which encourages them not to assert anything other than what can safely be derived from the sure basis of observation, this position is defeated or undermined by the very fact that all observation statements are theory dependent and also fallible.

Again, given the fact that scientific theories can lead to new predictions different from anything known before, should be or is an embarrassment for the instrumentalists. In other words, theories which for them, are mere calculating devices, can lead to discovery of new kinds of observable reality by way of concepts which they regard as theoretical fictions. Some specific examples will make this clear. The concept that molecular structure of some compounds should consist of closed rings of atoms was initially proposed by Kekule, with benzene as the parent compound. He had an instrumentalist attitude towards his theory and thus, regarded his ring structures only as useful theoretical fictions.[30] However, these theoretical fictions can be seen almost directly through an electron microscope. Similarly, instrumentalists who defend the kinetic theory of gases as theoretical fictions, should have been discouraged, to see the result of collisions of what they called theoretical fiction with smoke particles in the Brownian motion phenomenon. Again, Hertz claimed that he had been able to produce the fields noted by Maxwell’s electromagnetic theory in a “visible and almost tangible form.”[31]  All these questions undermine the claim of instrumentalists that theoretical entities are fictitious and unreal unlike observable ones.       

INSTRUMENTALISM AND THE CONCEPT OF TRUTH

From what we have so far, realism entails the concept of truth, since for the realist, the object of science is truth (i.e. true descriptions of the physical world). From this perspective any scientific theory that gives correct description of some aspect of the universe and its behavioral mode is true, while the one that does not give the correct description is regarded as false. [32]

“Instrumentalism will also typically involve a notion of truth, but in a more restricted way. Descriptions of the observable world will be true or false according to whether or not they correctly describe it. However, the theoretical constructs, that are designed to give us instrumental control of the observable world, will not be judged in terms of truth or falsity but rather in terms of their usefulness as instruments.”[33]

CONCLUSION

Science as robust as it is with its claim to presenting reality in its true sense has in this essay been seen to fall short of its claims. It lays claim to certainty of scientific theories capturing reality in structure, and made manifest in its success. The instrumentalist tries to puncture this claim by saying that theories are mere instruments for making predictions. They also question the authenticity of the truth claims of scientific realism. This criticism against it proves cogent in the light of history and reason.

However, on the grounds of developing the human race, helping humanity make predictions and solve questions, science has done pretty well. The questions now is, do we intend to hold onto the search for indubitable truth about everything in the universe before we act, even if it will take us eternity to arrive at it, or carry on with life with its uncertainties by taking a leap of faith in the direction of science? The choice is ours!

BIBLIOGRAPHY

A.F., Chalmers. What Is This Thing Called Science, Second Edition. Great Britain: Open University Press, 1982.

_____________, What Is This Thing Called Science, Third Edition. Great Britain: Hackett Publishing Company, Inc. 1999.

Batitsky, Vadim. Foundations of Science. Netherlands: Kluwer Academic Publishers, 2000. Vol. 5, Issue 3, p. 299.

Boyd, Richard. "Realism, Approximate Truth and Philosophical Method", In The Philosophy of Science, edited by D. Papineau. Oxford: Oxford University Press, 1996. 215-255.

Diéguez-Lucena, Antonio. “Why Does Laudan’s Confutation of Convergent Realism Fail?”, Journal for General Philosophy of Science, no. 37, (2006), p. 393-403

Hume, David. An Enquiry Concerning Human Understanding. Edited by Charles W. Hendel. New York: Charles Scribner’s Sons, 1955.

Koethe, John. “Putnam's Argument Against Realism”, The Philosophical Review Vol. 117, No. 2, (January 1979), URL: http://www.jstor.org/stable/2184780

Ladyman, James. Understanding Philosophy of Science. London: Taylor & Francis Group.

Larry, Laudan. "A Confutation of Convergent Realism", In The Philosophy of Science, edited by D. Papineau. Oxford: Oxford University Press, 1996, pp. 107-138.

Lemos, Noah. An Introduction to the Theory of Knowledge. New York: Cambridge University Press, 2007.

Psillos, Stathis. Scientific realism: How Science Tracks Truth. Taylor and Francis, 2005.

Sarkar, Sahotra & Pfeifer, Jessica, The philosophy Science: An Encyclopedia. New York: Routledge, Taylor & Francis Group.

Votsis, Ioannis. The Scientific Realism Debate.  http://www.votsis.org/PDF/The_ Scientific_Realism_Debate.pdf

http://lizhuoyao.wordpress.com/2010/10/30/realism-vs-instrumentalism

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[1] Cf. Chalmers A. F., What is this thing called science? An assessment of the nature and status of science and its methods (Milton Keyness; Open University Press.1982), p. 147

[2] Chalmers A. F., What is this thing called science? p. 147.

[3]Ioannis Votsis, The Scientific Realism Debate.  http://www.votsis.org/PDF/The_ Scientific_Realism_Debate.pdf

[4] http://lizhuoyao.wordpress.com/2010/10/30/realism-vs-instrumentalism/

[5] Sahotra Sarkar & Jessica Pfeifer, The philosophy Science: An Encyclopedia (New York: Routledge, Taylor & Francis Group, 2006), p. 725

[6] Sahotra Sarkar & Jessica Pfeifer, The philosophy Science: An Encyclopedia, p. 725

[7] James Ladyman , Understanding Philosophy of Science (New York: Taylor & Francis Group, 2002), p. 129

[8] Antonio Diéguez-Lucena, “Why Does Laudan’s Confutation of Convergent Realism Fail?”, Journal for General Philosophy of Science, no. 37, (2006), p. 393.

[9] Chalmers A.F., What Is This Thing Called Science, Second Edition (Great Britain: Open University Press, 1982), p. 146.

[10] Chalmers A.F., What Is This Thing Called Science, Third Edition (Great Britain: Hackett Publishing Company, Inc. 1999), p. 228.

[11] Noah Lemos, An Introduction to the Theory of Knowledge (New York: Cambridge University Press, 2007), p. 9.

[12] Richard Boyd, "Realism, Approximate Truth and Philosophical Method", In The Philosophy of Science, edited by D. Papineau (Oxford: Oxford University Press, 1996) 215-255.

[13]Ioannis Votsis, The Scientific Realism Debate.  http://www.votsis.org/PDF/The_ Scientific_Realism_Debate.pdf

[14] Chalmers A.F., What Is This Thing Called Science, Third Edition (Great Britain: Hackett Publishing Company, Inc. 1999), p. 232.

[15] Noah Lemos, An Introduction to the Theory of Knowledge (New York: Cambridge University Press, 2007), p. 10.

[16] Chalmers A.F., What Is This Thing Called Science, Third Edition (Great Britain: Hackett Publishing Company, Inc. 1999), p. 233

[17] Vadim Batitsky, Foundations of Science (Netherlands: Kluwer Academic Publishers, 2000), Vol. 5, Issue 3, p. 299.

[18] James Ladyman, Understanding Philosophy of Science (London: Taylor & Francis Group, 2002), p. 138

[19] John Koethe, “Putnam's Argument Against Realism”, The Philosophical Review Vol. 117, No. 2, (January 1979), p. 92  URL: http://www.jstor.org/stable/2184780

[20] Antonio Diéguez-Lucena, “Why Does Laudan’s Confutation of Convergent Realism Fail?”, Journal for General Philosophy of Science, no. 37, (2006), pp. 395-396.

[21] Larry Laudan, "A Confutation of Convergent Realism", In The Philosophy of Science, edited by D. Papineau (Oxford: Oxford University Press, 1996), p 119.

[22] Stathis Psillos, Scientific realism: How Science Tracks Truth (Taylor and Francis, 2005) p. 120.

[23] David Hume, An Enquiry Concerning Human Understanding, Section II, Part II, p. 125

[24] David Hume, An Enquiry Concerning Human Understanding, Section II, Part II, p. 126.

[25] David Hume, An Enquiry Concerning Human Understanding, Section II, Part II, p. 127.

[26] Antonio Diéguez-Lucena, p. 400.

[27] Cf. Chalmers A.F., What Is This Thing Called Science, Third Edition (Great Britain: Hackett Publishing Company, Inc. 1999), pp. 146-147.

[28] Chalmers A.F., Third Edition, pp. 147-148

[29] Chalmers A.F., Third Edition, p. 148

[30] Chalmers A.F., Third Edition, p. 148

[31] Chalmers A.F., Third Edition, p. 148

[32] Cf. Chalmers A.F., Third Edition, p. 147

[33] Chalmers A.F., Third Edition, p. 147