SCIENTIFIC REALISM AND ANTI-REALISM

SCIENTIFIC REALISM AND ANTI-REALISM Dr. Harry Firman harryfirman510@gmail.com Abstract Science examines observable and unobservable entities. There are different metaphysical views of the truth of knowledge in the unobservable domain, especially entities that are theoretical constructs. Realism sees unobservable knowledge as true as long as the deduction from that knowledge is empirically proven. Anti-realism, on the other hand, rejects this view based on historical experience; many theoretical constructs that were originally seen as truth have been later proven to be incorrect. On that basis, anti-realism views theoretical constructs as not to be seen as truth, but only as instruments to explain and predict phenomena. Kata kunci: sains, realisme, anti-realisme, no-miracle argument, instrumentalisme. 1. Introduction In philosophy of science context, realism is the view that we can know scientific theories which refer to unobservavle entities that exist independently of our minds. Conversely, anti-realism is the view that denies scientific theories which refers to mind-independent unobservable entities. There is an ongoing debate between realism versus anti-realism in viewing the truth of scientific knowledge, which is based on different views of unobservable reality as knowledge in science. This paper presents the issue of unobservable reality in science, and arguments that releases by both realism and anti-realism in their strong debates, such as realists’ no miracle argument versus anti-realists’ underdetermination argument, and finally the birth of the concept of instrumentalism proposed by anti-realists as an approach to ease up the debate. 2. Two Types of Reality: The Observable and the Unobservable Modern science describes in detail the existing reality and the natural laws that govern that reality, from the internal structure of the atom to the life cycle of the stars. Various entities postulated by modern science, such as genes, viruses, black holes, and electromagnetic radiation, are unobservable reality, at least by the senses directly. Therefore, the question is, should we believe what science explains about the reality behind the visible? This issue has become a hot debate in the philosophy of science, especially between the schools of thought "realisme" and "anti-realisme" from the 19th century up to the present day (Ladyman, 2002). A number of scientific knowledges can be categorized into observable knowledge, e.g. metals, acids, solubility, and reactivity. Whether it is true or not is determined based on observation. In addition, there are other categories, namely unobservable scientific knowledge that cannot be observed, such as atomic structure, molecular energy levels, intermolecular interactions. Scientific theories involve unobserved entities, as in molecular kinetic theory. The kinetic theory of gas molecules, states that gases contain many very small entities (molecules) that are constantly in motion". Molecular entities are unobservable. However, from kinetic theory we can deduce various consequences about the observed behavior of gases (observable). For example, heating a sample of gas at constant pressure causes it to expand, and this prediction can be proven experimentally. Many theories involve unobservable entities, but are postulated to explain facts. 3. The Realism versus The Anti-Realism Metaphysical Views 3.1 The Realism View The metaphysical view of realism states that reality is exsist and free from human thought and perception (mind-independent reality). The concept of "reality free of thoughts and perceptions" implies that there is a world behind our perceptions, and we can know whether those perceptions are accurate or not. However, if reality does not exist or we do not have access to it, then there is no way to check whether our perceptions correspond to reality. Based on this thinking, realism views invisible objects (unobservable) postulated by scientific theories as reality (Southwell, 2013). Realists convinced that the purpose of science is to provide a correct description of nature, but they disagree that knowledge is limited by observation. Moreover, realists believe that there has been a great deal of scientific knowledge involving unobserved reality. If the atomic theory can explain many facts, then it is proof that the atomic theory is true. Therefore, there is no reason to say that atomic theory does not describe reality, simply because atoms are not observable. 3.2 The Anti-Realism View The anti-realism school of thought rejects the metaphysical view of realisme which states that there is a reality free of thought. Based on that belief, anti-realist view science as unable to reach the unobservable. Anti-realists believe that the goal of science is to provide a correct description of only certain parts of nature, namely the observable part (Southwell, 2013). Anti-realists argue that we cannot attain knowledge of the unobservable parts of reality. Based on the view of anti-realism, scientific knowledge must be within the territory reached by observation. Anti-realism believes that only observable entities exist. According to anti-realism, science can give us knowledge about fossils, trees, animals (observable), but it does not provide knowledge about unobservable atoms, electrons, chemical bonds, etc. To anti-realists, unobservable entities are merely "wishful thinking" concocted by scientists to explain observed phenomena. 4. Realists’ No Miracle Argument versus Anti-realists’ Underdetermination Argument” 4.1 No Miracle Argument Many theories involving unobserved entities are empirically successful, predicting the behavior of objects in the observable world, including the kinetic theory of gas molecules. The empirical success of theories involving unobservable entities laid the foundation for the strongest argument for scientific realism, referred to as the "no miracle argument". This argument was put forward by Hilary Putnam who stated that the success of science in predicting new phenomena and applied it in technology is miraculous if theories do not correctly identify unobserved entities and processes that underlie what we observe (Ladyman, 2002). According to this argument, it would be a miracle that a theory of electrons and atoms succeeded in predicting the observed reality if electrons and atoms did not exist. If atoms and electrons do not exist, what is the reason for the relationship between theory and observed facts? The potential of a theory to explain phenomena becomes evidence for the truth of the theory itself. The anti-realis response to the "No-Miracle Argument" is that in the history of science there have been many cases where theories that are now believed to be incorrect, but empirically successful in their day. For example, the "phlogiston" theory of combustion; the theory of "ether" as a medium of light radiation; the calor theory of heat, and the "generatio spontaneous theory". Anti-realists, therefore, argue that the "nomiracle argument" is questionable. However, the anti-realist view faces the problem that if the theory is never correct, the experiments carried out to confirm the theory are a waste of time. Something that is contrary to the reality of scientific activity, where experiments are practiced by scientists from the past until now. 4.2 Underdetermination Argument "Underdetermination" is the view that facts do not determine a theory, because there is no single theory for a fact, but there are a number of theories that match (match or compatible) with facts (Southwell, 2013). Instead, theories determine facts, as in the case of the kinetic theory of gas molecules, for which observational data are clearly determined by the theory. The data are observed to provide strong evidence for the existence of the observed entity. This argument used by anti-realists to claim that unobservable knowledge is impossible. Not only one theory explains the same phenomenon, for example Darwin's theory and Lammarck's theory explain the phenomenon of evolution of species on earth. Another case, regarding the phenomenon of "bonding" in chemistry, there are two modern theories (based on quantum mechanics) that explain it, namely MO theory (molecular orbital theory) and VB theory (valence bond theory). With different assumptions, both theories succeed in explaining the same fact. Such cases show that it is difficult for the unobservable entities postulated by the theories to be verified. 5. Observable and Detectabe Philosophically, the distinction between observable and unobservable raises ontological issues. Entities such as electrons are obviously not observed in the simple sense, but their existence can be detected using instruments. Electrons cannot be observed directly, but can be detected. George Maxell, an American philosopher, stated that there is a continuum of observation, from observation with the naked eye to observation with sophisticated tools. Therefore, it is difficult to distinguish between observation and nonobservation. We cannot be sure which is classified as observation and not observation. For example, can biologists observe microorganisms with a high-magnification microscope, or can simply detect the presence of microorganisms. Therefore, the antirealist attempts to separate the observed entity from the unobserved entity is seen as a major mistake from anti-realism (Ladyman, 2002). 6. Instrumentalism According to anti-realists, whether gas really contains molecules that are always in motion does not matter. However, kinetic theory does not actually describe hidden facts, but merely provides an easy way (instrument) to predict observations. Therefore, anti-realism is often called "instrumentalism". In essence, scientific theory is an instrument to help scientists predict observable phenomena, but "not as an attempt to describe reality" (Ladyman, 2002). Anti-realists analogize theory with a hammer. The hammer does have a role in producing a product, but does not represent the product itself (Mannoia, 1980). For instrumentalists, theory is a tool that shows connections between phenomena that previously appeared unrelated, but theory does not represent or even describe those phenomena. "Theories are useful but they are not the truth". References Ladyman, J. (2002). Understanding philosophy of science. London: Routledge. Mannoia, V. J. (1986). What is science?: An introduction to the structure and methodology of science. Lenham, MD: University Press of America. Southwell, G. (2013). 50 philosophy of science ideas you really need to know. London: Quercus Editions. Thomspson, M. (2012). Understand philosophy of science. London: Hodder Education.