Popper: Scientific Realism

The question of truth is a broadly broached subject in Philosophy as it features along the entire historical and polemical growth of the discipline right from the time of the Ancients down to our Post-Modern era. Yet, the delimiting realization of being unable to register general success in our dogged attempts at truth and knowledge, mostly stares us blankly in the face, for matters on which philosophy endeavours to speculate on, are beyond the reach of definite knowledge.1 Our theories of (...) the universe open up to modifications, refutations, and further propositions, evidencing a historical development in philosophical inquiry. This generally is the growth of our science, of our knowledge. This paper critically seeks to examine Popper’s notion of verisimilitude. It takes us through the scientist’s journey from ignorance to truth, and the difference between probability and verisimilitude. It addresses the relevance of the theory of content in understanding verisimilitude, under its distinctions as quantitative and qualitative. Finally, it discusses corroboration and the criteria for theory-choice. (shrink)

Karl Popper (1902-1994) was one of the most influential philosophers of science of the 20th century. He made significant contributions to debates concerning general scientific methodology and theory choice, the demarcation of science from non-science, the nature of probability and quantum mechanics, and the methodology of the social sciences. His work is notable for its wide influence both within the philosophy of science, within science itself, and within a broader social context. Popper’s early work attempts to solve the problem of (...) demarcation and offer a clear criterion that distinguishes scientific theories from metaphysical or mythological claims. Popper’s falsificationist methodology holds that scientific theories are characterized by entailing predictions that future observations might reveal to be false. When theories are falsified by such observations, scientists can respond by revising the theory, or by rejecting the theory in favor of a rival or by maintaining the theory as is and changing an auxiliary hypothesis. In either case, however, this process must aim at the production of new, falsifiable predictions. While Popper recognizes that scientists can and do hold onto theories in the face of failed predictions when there are no predictively superior rivals to turn to. He holds that scientific practice is characterized by its continual effort to test theories against experience and make revisions based on the outcomes of these tests. By contrast, theories that are permanently immunized from falsification by the introduction of untestable ad hoc hypotheses can no longer be classified as scientific. Among other things, Popper argues that his falsificationist proposal allows for a solution of the problem of induction, since inductive reasoning plays no role in his account of theory choice. Along with his general proposals regarding falsification and scientific methodology, Popper is notable for his work on probability and quantum mechanics and on the methodology of the social sciences. Popper defends a propensity theory of probability, according to which probabilities are interpreted as objective, mind-independent properties of experimental setups. Popper then uses this theory to provide a realist interpretation of quantum mechanics, though its applicability goes beyond this specific case. With respect to the social sciences, Popper argued against the historicist attempt to formulate universal laws covering the whole of human history and instead argued in favor of methodological individualism and situational logic. Table of Contents 1. Background 2. Falsification and the Criterion of Demarcation a. Popper on Physics and Psychoanalysis b. Auxiliary and Ad Hoc Hypotheses c. Basic Sentences and the Role of Convention d. Induction, Corroboration, and Verisimilitude 3. Criticisms of Falsificationism 4. Realism, Quantum Mechanics, and Probability 5. Methodology in the Social Sciences 6. Popper’s Legacy 7. References and Further Reading a. Primary Sources b. Secondary Sources -/- . (shrink)

Karl Popper fut un réaliste scientifique malgré lui. Au mépris de ses propres restrictions concernant les formes de raisonnement scientifique acceptables et la portée de l’évidence empirique, il insista sur une conception fortement réaliste des buts et des accomplissements de la science. Dans cet article, je construis une défense générale du réalisme scientifique, m’appuyant, au il des développements, sur celles des positions popperiennes qui font progresser l’argument, et critiquant celles qui l’entravent. Bien que la ligne argumentative d’ensemble soit mienne, je (...) montre, par des attributions directes, que Popper partage mes conclusions réalistes, et pourquoi il les partage. (shrink)

Take the following version of scientific realism: we have good reason to believe that (some of the) current scientific theories tell us something specific about the underlying, i.e. unobservable, structures of the world, for instance that there are electrons with a certain electric charge, or that there are viruses that cause certain diseases. Popper, the rationalist, would not have adhered to the proposed formulation of scientific realism in terms of the rationality of existential beliefs concerning unobservables. Popper did not believe (...) in belief. According to Van Fraassen, the empiricist, one may yet have a rational existential belief concerning unobservables, given a liberal notion of rationality of belief. In this paper I will investigate to what extent a reassessment of both Popper’s rejection of the rationality of belief and Van Fraassen’s reformulation of the rationality of belief, points towards a new and pragmatist dissolution of the ‘problem of scientific realism’. (shrink)

Alan Musgrave is one of the foremost contemporary defenders of scientific realism. He is also one of the leading exponents of Karl Popper’s critical rationalist philosophy. In this paper, my main focus will be on Musgrave’s realism. However, I will emphasize epistemological aspects of realism. This will lead me to address aspects of his critical rationalism as well.

Unlike almost all other philosophers of science, Karl Popper sought to contribute to natural philosophy or cosmology – a synthesis of science and philosophy. I consider his contributions to the philosophy of science and quantum theory in this light. There is, however, a paradox. Popper’s most famous contribution – his principle of demarcation – in driving a wedge between science and metaphysics, serves to undermine the very thing he professes to love: natural philosophy. I argue that Popper’s philosophy of science (...) is, in this respect, defective. Science cannot proceed without making highly problematic metaphysical assumptions concerning the comprehensibility and knowability of the universe. Precisely because these assumptions are problematic, rigour requires that they be subjected to sustained critical scrutiny, as an integral part of science itself. Popper’s principle of demarcation must be rejected. Metaphysics and philosophy of science become a vital part of science. Natural philosophy is reborn. A solution to the problem of what it means to say a theory is unified is proposed, a problem Popper failed to solve. In The Logic of Scientific Discovery, Popper made important contributions to the interpretation of quantum theory, especially in connection with Heisenberg's uncertainty relations. Popper's advocacy of natural philosophy has important implications for education. (shrink)

This dissertation describes and assesses Karl Popper's commonsense realism. The evaluation focuses upon his arguments against nonrealism in modern physics rather than his purely philosophical arguments. Motivated by a few central concepts, Popper presented a detailed critique of the orthodox interpretation of physics. He created a "quantum mechanics without an observer" based upon an "epistemology without a subject." ;Popper believed that certain philosophical presuppositions were necessary for progressive and objective science. He claimed that a "serious crisis exists in modern physics" (...) due to the suspension of realism. Popper subsequently presented an elaborate reinterpretation of quantum theory in attempt to reinstate a realistic and objectivist conceptual framework. He also supported the EPR thought experiment which he was convinced demonstrated the incompleteness of quantum theory and the subsequent unnecessary nonrealistic interpretation. ;Important presuppositions and contraints of Popper's realism not explicit in his purely philosophical work are manifested in his philosophical physics. The EPR test proposal crystallized his argument against positivism in physics. Thus, in light of the recent testing of the EPR paradox, I evaluate Popper's philosophical presuppositions and inquire whether classical realism needs revision. ;The dissertation's goal is this assessment of Popper's concepts underlying his attack upon modern physics. Rather than an abstract analysis of his concepts, I assess them in the context of the current quantum theoretical debates and recent testing of the EPR proposal. ;The dissertation is in the "history of ideas" style. I describe Popper's general philosophy of science, the challenge to his realism by modern physics and the Copenhagen Interpretation, Popper's realistic reinterpretation of quantum theory and the inadequacies of this project . I then evaluate his commonsense realism on the basis of his presuppositions of his project. I conclude that Popper's constraints were norms derived from classical science and were overly dependent upon intuitive, traditional notions. These constraints then can be incompatible with counter-intuitive notions of contemporary theoretical science. I also suggest that Popper's ontological dichotomies are biased by classical notions. (shrink)

Two views of the role of truth as an aim of inquiry are contrasted: The Peirce-Popper or messianic view of approach to the truth as an ultimate aim of inquiry and the myopic view according to which a concern to avoid error is a proximate aim common to many otherwise diverse inquiries. The messianic conception is held to be responsible for the tendency to conflate fallibilism with corrigibilism and for the consequent problems faced by Peirceans and Popperians alike in squaring (...) the alleged relevance of the fruits of scientific inquiry for practice while insisting on the corrigibility of knowledge. Myopic realism is advocated as promising escape from these difficulties. (shrink)