According to falsificationism, a theory is scientific if it can be incompatible with some empirically testable statements. This epistemological approach has been criticized because, in practice, it is impossible to decide when a particular fact should be considered incompatible with a theory. These criticisms, however, neglect the fact that the Popperian sense of falsification is a “logical sense.” Thus, the Popperian criterion of falsifiability only requires that, assuming certain auxiliary hypotheses, the theory in question be logically incompatible with some empirically (...) testable statements. This paper presents a reassessment of these criticisms, justifying that the criterion of falsifiability is unrenounceable insofar as our best theories should aspire to satisfy it. (shrink)

Ever since the first meeting of the proponents of the emerging Logical Empiricism in 1923, there existed philosophical differences as well as personal rivalries between the groups in Berlin and Vienna, headed by Hans Reichenbach and Moritz Schlick, respectively. Early theoretical tensions between Schlick and Reichenbach were caused by Reichenbach’s Kantian roots, who himself regarded the Vienna Circle as a sort of anti-realist “positivist school”—as he described it in his Experience and Prediction. One result of this divergence was Schlick’s preference (...) of Carnap over Reichenbach for a position at the University of Vienna, and his decision not to serve as a co-editor with Reichenbach for the journal Erkenntnis that they jointly established in 1930. A second split rooted in different views on induction and probability, which culminated in the Hans Reichenbach’s refusal to serve as an invited author on probability within the International Encyclopedia of Unified Science series ed. by Rudolf Carnap, Charles Morris and Otto Neurath from 1938 onwards. In this regard it is remarkable that also Richard von Mises, who was the second leading figure of Logical Empiricism in Turkish exile, criticized the theory of probability put forward by his former Berlin colleague. In this paper I analyse this controversial exchange, drawing on the relevant correspondence and asking whether these philosophical differences were a typical feature of the pluralism inherent in Logical Empiricism in general. (shrink)

In the methodology of scientific research programs (MSRP) there are important features on the problem of prediction, especially regarding novel facts. In his approach, Imre Lakatos proposed three different levels on prediction: aim, process, and assessment. Chapter 5 pays attention to the characterization of prediction in the methodology of research programs. Thus, it takes into account several features: (1) its pragmatic characterization, (2) the logical perspective as a proposition, (3) the epistemological component, (4) its role in the appraisal of research (...) programs, and (5) its place as a value for scientific research. -/- The notion of “novel facts” is highly relevant in his conception, where several aspects are involved: the directions of novel facts, the different kinds of novelty, and the transition from six possible options of “novel facts” to four choices. Thereafter, the prediction of novel facts as the criterion of appraisal is considered. On the one hand, this requires analyzing the theoretical, empirical, and heuristic possibilities of appraisal; and, on the other, whether there is an overemphasis on the role of prediction in methodology of scientific research programs. As a consequence, there is an analysis of Lakatos’ criterion of appraisal in MSRP and economics. (shrink)

Do the terms “logical positivism” and “logical empiricism” mark a philosophically real and significant distinction? There is, of course, no doubt that the first term designates the group of philosophers known as the Vienna Circle, headed by Moritz Schlick and including Rudolf Carnap, Herbert Feigl, Philipp Frank, Hans Hahn, Otto Neurath, Friedrich Waismann and others. What is debatable, however, is whether the name “logical positivism” correctly distinguishes their doctrines from related ones called “logical empiricism” that emerged from the Berlin Society (...) for Scientific Philosophy around Hans Reichenbach which included Walter Dubislav, Kurt Grelling, Kurt Lewin and a young Carl Gustav Hempel.1 The .. (shrink)

This study reconstructs the 1928–1929 correspondence between Reichenbach and Einstein about the latter’s latest distant parallelism-unified field theory, which attracted considerable public attention at the end of the 1920s. Reichenbach, who had recently become a Professor in Berlin, had the opportunity to discuss the theory with Einstein and therefore sent him a manuscript with some comments for feedback. The document has been preserved among Einstein’s papers. However, the subsequent correspondence took an unpleasant turn after Reichenbach published a popular article on (...) distant parallelism in a newspaper. Einstein directly wrote to the Editorial Board complaining about Reichenbach’s unfair use of off-the-record information. While Reichenbach’s reply demonstrates a sense of personal betrayal at Einstein’s behavior, his published writings of that period point to a sense of intellectual betrayal of their shared philosophical ideals. In his attempts to unify both electricity and gravitation, Einstein had abandoned the physical heuristic that guided him to the relativity theory, to embrace a more speculative, mathematical heuristic that he and Reichenbach had both previously condemned. A decade-long personal and intellectual friendship grew fainter and then never recovered. This study, relying on archival material, aims to revisit the Reichenbach–Einstein relationship in the late 1920s in light of Reichenbach’s neglected contributions to the epistemology of the unified field theory program. Thereby, it hopes to provide a richer account of Reichenbach’s philosophy of space and time. (shrink)

This note presents a very brief history of the observation that the probability of the material conditional A⊃B is in general different from, but cannot be less than, the conditional probability of B given A. The difference between the two probabilities is significant for the interpretation of conditionals and for the possibility of inductive probability. It can be quantitatively specified in so-called ‘excess laws’ for which Popper appears to have claimed priority. I argue that such a priority claim should be (...) rejected and credit should instead be given, if to anyone, to Boole and Reichenbach instead. (shrink)

Despite wide recognition that speculation is critical for successful science, philosophers have attended little to it. When they have, speculation has been characterized in narrowly epistemic terms: a hypothesis is speculative due to its (lack of) evidential support. These ‘evidence-first’ accounts provide little guidance for what makes speculation productive or egregious, nor how to foster the former while avoiding the latter. I examine how scientists discuss speculation and identify various functions speculations play. On this basis, I develop a ‘function-first’ account (...) of speculation. This analysis grounds a richer discussion of when speculation is egregious and when it is productive, based in both fine-grained analysis of the speculation’s purpose, and what I call the ‘epistemic situation’ scientists face. (shrink)

In the late 1930s, a few years before the start of the Second World War, a small number of European philosophers of science emigrated to the United States, escaping the increasingly perilous situation on the continent. Among the first expatriates were Rudolf Carnap and Hans Reichenbach, arguably the most influential logical empiricists of their time. In this two-part paper, I reconstruct Carnap’s and Reichenbach’s surprisingly numerous interactions with American academics in the decades before their move in order to explain the (...) impact of their arrival in the late 1930s. This second part traces Reichenbach’s development and focuses on his frequent interactions with American academics throughout the 1930s. I show that Reichenbach was quite ignorant about developments in Anglophone philosophy in the first stages of his career but became increasingly focused on the United States from the late 1920s onwards. I reconstruct Reichenbach’s efforts to find a job across the Atlantic and show that some of his English publications—most notably Experience and Prediction—were attempts to change the American narrative about logical empiricism. Whereas U. S. philosophers identified scientific philosophy with the views of the Vienna Circle, Reichenbach aimed to market his probabilistic philosophy of science as a subtler alternative. (shrink)

In the years before the Second World War, Rudolf Carnap and Hans Reichenbach emigrated to the United States, escaping the quickly deteriorating political situation on the continent. Once in the U. S., the two significantly changed the American philosophical climate. This two-part paper reconstructs Carnap’s and Reichenbach’s surprisingly numerous interactions with American academics in the decades before their move in order to explain the impact of their arrival in the late 1930s. Building on archival material of several key players and (...) institutions, I take some first steps toward answering the question why logical empiricism became so successful in the United States after the War. This first part reconstructs Carnap’s development between 1923, when he first visited New York, and 1936, when he was offered a position at the University of Chicago. I describe Carnap’s first substantive contacts with American philosophers as well as the events leading up to his decision to emigrate. In addition, I argue that some of Carnap’s work from the mid-1930s—in particular “Testability and Meaning”—can be better understood if we take into account his attempts to correct the American narrative about logical positivism and his increasingly desperate efforts to find a position in the United States. (shrink)

I would like to assume that Reichenbach's distinction of Justification and Discovery lives on, and to seek arguments in his texts that would justify their relevance in this field. The persuasive force of these arguments transcends the contingent circumstances apart from which their genesis and local transmission cannot be made understandable. I shall begin by characterizing the context distinction as employed by Reichenbach in "Experience and Prediction" to differentiate between epistemology and science (1). Following Thomas Nickles and Kevin T. Kelly, (...) one can distinguish two meanings of the context distinction in Reichenbach's work. One meaning, which is primarily to be found in the earlier writings, conceives of scientific discoveries as potential objects of epistemological justification. The other meaning, typical for the later writings, removes scientific discoveries from the possible domain of epistemology. The genesis of both meanings, which demonstrates the complexity of the relationships obtaining between epistemology and science, can be made understandable by appealing to the historical context (2). Both meanings present Reichenbach with the task of establishing the autonomy of epistemology through the justification of induction. Finally, I shall expound this justification and address some of its elements of rationality characterizing philosophy of science(3). (shrink)

Reichenbach emphasizes the central importance of prediction, which is—for him—the principal aim of science. This paper offers a critical reconstruction of his concept of prediction, taking into account the different periods of his thought. First, prediction is studied as a key factor in rejecting the positivism of the Vienna Circle. This part of the discussion concentres on the general features of prediction before Experience and Prediction (EP) (section 1). Second, prediction is considered in the context of Reichenbach's disagreements with his (...) contemporaries—Carnap and Popper—(section 2). Pointing out these differences gives an additional basis for understanding how Reichenbach saw “prediction” in the period when EP was written. Third, Reichenbach's theoretical framework of prediction is analysed following EP. This analysis studies the semantical, logical, epistemological and methodological bases of his concept of prediction (section 3). Fourth, Reichenbach's conception of prediction, based on an objectivist interpretation of probabilities, is compared with the perspective on prediction of subjective Bayesians (the present personalists). This comparison (section 4) illustrates Reichenbach's views regarding the links of prediction with probability. Fifth, innovations and elements of continuity after EP are noted which give a more complete picture of Reichenbach's thought on prediction (section 5). This contributes to a comprehensive characterization of his concept of prediction. Finally, there is an assessment of his whole view of the matter and a presentation of the ingredients for a satisfactory alternative (section 6). (shrink)