Philosophy of Science: An Encyclopedia

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Vienna Circle, The

The Vienna Circle consisted of a group of about three dozen researchers drawn from the natural and social sciences, logic, and mathematics, which met regularly in Vienna between the two World Wars to discuss philosophy. The work of this group constitutes one of the most important and most influential philosophical contributions of the twentieth century, in particular in the development of analytic philosophy and history and philosophy of science (Stadler 2001, 2003a).

The Vienna Circle was first publicly announced in 1929 with the publication of what came to be called its manifesto, Wissenschaftliche Weltauffassung. Der Wiener Kreis (The Scientific Conception of the World: The Vienna Circle), edited by the Verein Ernst Mach (Ernst Mach Society) and authored by Rudolf Carnap, Hans Hahn, and Otto Neurath (Carnap et al. 1929). The Vienna Circle was essentially a modernist movement, at the center of which was the so-called "Schlick Circle", a discussion group organized in 1924 by Moritz Schlick. Rudolf Carnap, Herbert Feigl, Philipp Frank, Kurt Gödel, Hans Hahn, Otto Neurath, Felix Kaufmann, Viktor Kraft, Karl Menger, Friedrich Waismann and Edgar Zilsel belonged to its inner circle (see CARNAP, RUDOLF; HAHN, HANS; NEURATH, OTTO, SCHLICK, MORITZ). Their meetings were also attended by Olga Taussky-Todd, Olga Hahn-Neurath, Rose Rand, Gustav Bergmann and Richard von Mises, and on several occasions by visitors such as Hans Reichenbach, Alfred J. Ayer, Ernest Nagel, Willard Van Orman Quine and Alfred Tarski. Members of the periphery, most of them as participants, were Egon Brunswik, Karl Bühler, Josef Frank, Else Frenkel-Brunswik, Heinrich Gomperz, Carl Gustav Hempel, Eino Kaila, Hans Kelsen, Charles Morris, Arne Naess, Karl Popper, Frank P. Ramsey, Kurt Reidemeister, and the alleged "genius", Ludwig Wittgenstein, who had a special influence on some members of the group (see AYER, ALFRED JULES; HEMPEL, CARL GUSTAV; NAGEL, ERNEST; POPPER, KARL; QUINE, WILLARD VAN; RAMSEY, FRANK PLUMPTON; REICHENBACH, HANS). In addition, the mathematician Karl Menger organized in the years 1926-36 an international "Mathematical Colloquium", which was attended by Kurt Gödel, John von Neumann, and Alfred Tarski among many others (Menger 1994).

This international and interdisciplinary discussion circle was pluralistic and committed to the ideals of the Enlightenment. It was unified by the aim of making philosophy scientific with the help of modern logic on the basis of experimental and everyday experience. The general aims of the movement were expressed in its publications such as the two book series, Schriften zur Wissenschaftlichen Weltauffassung (Publications on the Scientific Conception of the World) 1929-37 with eleven volumes, Einheitswissenschaft (Unified Science) 1933-38 with seven volumes, the journal Erkenntnis 1930-40 (the 1939 volume was called Journal for Unified Science), and the International Encyclopedia of Unified Science 1938-70 (Neurath et al. 1971).

Given this story of scholarly success, the fate of the Vienna Circle was tragic. The Verein Ernst Mach was suspended in 1934 by Austro-Fascism for political reasons; Schlick was murdered in 1936, and, around this time, many members of the Circle were forced to leave Austria for racial and political reasons. Thus, soon after Schlick's death, the Circle disintegrated. As a result of the emigration of so many of its members and adherents, however, the Circle's ideas became more and more widely known, especially in Scandinavia, Britain, and North America, where they contributed hugely to the emergence of modern philosophy of science (Timms and Hughes 2003; Hardcastle and Richardson 2003). In Germany and Austria, however, the break that was caused by the forced emigration of the Vienna Circle's members was felt in the philosophical and mathematical scene for a long time (Heidelberger and Stadler 2003).

"Logical Positivism" and/or "Logical Empiricism"
The name 'Vienna Circle' was used for the first time in 1929 in the manifesto mentioned before. It was suggested by Neurath and was supposed to have a pleasant connotation similar to the "Vienna Woods" or the "Viennese Waltz". At the same time the term was to indicate the origin of this philosophical movement and its collective orientation (Frank 1949). In the programmatic essay of 1929 the position of the anti-metaphysical 'radical' left wing around Carnap, Neurath, Hahn, Frank, and others was especially prominent. This group supported the idea of a physicalist unity of science, most commonly referred to as 'logical empiricism' as found later in the program of the International Encyclopedia of Unified Science (Neurath 1946). By contrast, the more moderate wing of the Vienna Circle around Schlick, Waismann, Feigl, and others, emphasized their adherence to a dualism of science and philosophy with different names like 'consistent empiricism' (Schlick 1950, 462f.) or 'logical positivism' (Kraft 1950).

The widely used term 'logical positivism' actually originated in Blumberg and Feigl's (1931) article with that title, which was published in the Journal of Philosophy. Here both authors gave a concise description of the new anti-Kantian synthesis of logical and empirical factors proclaiming the impossibility of synthetic a priori truths. They went on to describe the philosophical transformation from the old to the new positivism with the adoption of symbolic logic, epistemology, and research into the foundations of science. Finally, they explained, following Wittgenstein, "the purpose of philosophy as the clarification of the meaning of propositions and the elimination of ... meaningless pseudo-propositions" (Blumberg and Feigl 1931, 269).

Scientific Philosophy and Philosophy of Science
Proponents of 'scientific philosophy' thought of philosophy not as an autonomous discipline existing prior to science but as a critical discipline dependent upon the results of the natural and social sciences, logic, and mathematics. Turning around Kant's dictum, they claimed that philosophy without science is empty, and science without philosophy is blind. Adoption of this scientific conception of philosophy does not, however, determine what epistemology, methodology, and ontology one is committed to. Nonetheless, all adherents of scientific philosophy demanded exact methods, a critical attitude, and a more or less empirical orientation. They opposed irrational and theological systems of philosophy (Systemphilosophie) and viewed science in general in a positive way.

Historically, Mach's philosophy provided the foundation for the development of the positions adopted within the Vienna Circle (see MACH, ERNST). The term 'logic of science' (Carnap's 'Wissenschaftslogik'; see Carnap 1934), known since the mid-1930s as 'philosophy of science', was later used to describe these positions (see CARNAP, RUDOLF). This implied a general scientific conception of philosophy as well as an attempt to provide a philosophy for all sciences (including human sciences). In addition, within the Vienna Circle, philosophy was regarded both as a form of linguistic analysis and as a discipline drawing on the foundations of the natural and social sciences.

At the same time there were divergences of philosophical approaches within the Vienna Circle. Those such as Schlick defended a methodological dualism of philosophy and science, and those such as Neurath sought to integrate philosophy altogether within a scientific conception of the world (see NEURATH, OTTO; and SCHLICK, MORITZ). In Schlick's view, the classical philosophical positions of empiricism and rationalism were integrated with the help of modern logic and mathematics, but a distinction between philosophy and science still remained. Neurath's more radical physicalism or 'encyclopedism' of logical empiricism aimed at overcoming philosophy itself within his collective project of an International Encyclopedia of the Unity of Science (Neurath 1946). This divergence in philosophical approaches left room for debates within the Circle on such topics as the merits of phenomenalist and physicalist languages, coherence and correspondence theories of truth, logical syntax and semantics, verification and confirmation, and ideal and natural languages. At the same time there was a certain consensus on the merits of logical analysis of language, a fallibilist epistemology, a scientific attitude to the world, and the unity of scientific explanation and knowledge in general.

The rivalry between Schlick's "consistent empiricism" and Neurath's physicalist unified science is a complex matter. Certain views were shared by both, such as the view of philosophy as a critique of language in accordance with Wittgenstein's philosophy of the Tractatus of 1922. However, while the principle of verification (see VERIFICATIONISM), logical atomism, and the picture theory of language are constitutive features of the entire movement, by themselves they do not characterize the Vienna Circle. Theoretical elements like logicism, verifiability, methodological phenomenalism and physicalism, a fallibilist theory of knowledge, conventionalism, and realism, together with an empiricist encyclopedism were cornerstones of the internal pluralistic development of logical empiricism from the 1930s onwards (see LOGICAL EMPIRICISM). This development also reflected the influence of Neurath's pragmatic point of view within the Circle. In particular, the objection towards any dualism of "language" and "world" (as "Wirklichkeitsphilosophie") with the attendant denial of any absolute "foundation of knowledge" (Schlick 1934) is representative of this nonreductive naturalism and methodological holism in the spirit of Pierre Duhem's and Henri Poincaré's philosophy of science (see CONVENTIONALISM; DUHEM THESIS; and POINCARÉ, HENRI). This form of relativism and naturalism already anticipated the pragmatic and historical turn after World War II in the philosophy of science which contributed to overcoming the linguistic turn and the so-called "received view" of philosophy of science.

The rejection of synthetic a priori judgments remained an important element of the logical empiricism of the Vienna Circle. According to Russell and Whitehead in the Principia Matematica (see RUSSELL, BERTRAND), symbolic logic and mathematics were regarded as purely analytical and a priori (independent of any experience). Analytic truths of these kinds were contrasted with contingent statements of the natural sciences and ordinary everyday experience, as synthetic a posteriori judgments (see ANALYTICITY). But there was no further class of synthetic a priori judgments: instead there was thought to be an important class of "meaningless" sentences, without any cognitive content. The elements of this class were seen as "metaphysical" in the sense that they are not part of knowledge at all even though they may express some realm of common sense experience (see COGNITIVE SIGNIFICANCE).

This position of the classical Vienna Circle is most prominently represented by Carnap's (1931) "Elimination of Metaphysics through Logical Analysis of Language", which developed a program for a unified rational reconstruction of science (see RATIONAL RECONSTRUCTION). But the question as to whether an empirical basis could serve as the foundation for all knowledge received strongly divergent answers from coherence theorists about truth influenced by Neurath and correspondence theorists influenced by Schlick (Hempel 1993). Also, the apparently strict distinction between analytic and synthetic sentences was questioned (Menger 1979, 1-60). The ideal of one language of science, logic, and mathematics was radically weakened within the Vienna Circle itself with Menger's and Carnap's principle of tolerance long before Quine (1953) put forward his critique of the "Two Dogmas of Empiricism" (see QUINE, WILLARD VAN ORMAN). Thus, contrary to popular belief, a heterogeneous pluralism of views was in fact characteristic of the Vienna Circle: for example, regarding ethics (Schlick, Menger, Kraft), the alternatives of realism versus positivism (Schlick, Carnap, Feigl, Kraft, Kaufmann), verificationism versus falsificationism (both positions criticized by Neurath), and last, but not least, in matters of ideological and political preference, for example, conservative liberalism vs. leftist socialism. In the later period of the Vienna Circle the contested verification principle was gradually abandoned and replaced by some form of a probabilistic confirmation methodology based on the principle of "connectibility" (von Mises 1951) (see COGNITIVE SIGNIFICANCE; VERIFIABILITY).

Scientific Conception of the World and Scientific Humanism
The unity of science movement with its six "International Congresses for the Unity of Science" (1935-1941) and the ambitious publication project "International Encyclopedia of Unified Science" (1938-1970) had a broader cultural meaning and goal, most notably the attempt to improve the human condition and to promote social reform and the intellectual struggle against irrationalism and totalitarian Weltanschauungen (see UNITY AND DISUNITY OF SCIENCE; UNITY OF SCIENCE MOVEMENT). It was a manifestation of a late-Enlightenment conception of science with a socially inspired anti-metaphysics. Between the two World Wars metaphysics was seen as a correlative feature of German idealism as well as of (Austro-) fascist 'universalism' as represented by the economist Othmar Spann.

The practical impulse behind this therapeutic destruction of metaphysical systems, then, was the desire for a scientific attitude based on human experience, directed against the Zeitgeist of totalitarian universalism and cultural pessimism (as criticized in Neurath [1921] and [1931]). Therefore, traditional philosophy, first of all, had to be reduced to a critical analysis of language, because most proponents of logical empiricism thought that an exact and sober usage of the scientific language is a precondition for all problem-oriented philosophizing - and moreover a sort of moral obligation.

Social criticism and collective work in philosophy of science formed a programmatic unity striving for a sweeping improvement of the human condition. Whereas in the natural sciences considerable progress had already been made, the situation in the social and cultural sciences was not so transparent, and was influenced by the ongoing Methodenstreit since the turn of the century (Kaufmann 1936). Although some members of the Vienna Circle like Kaufmann, Neurath, and Zilsel contributed essentially to this neglected field, their contributions have been largely ignored in the historiography on the Circle for a long time. In this respect it is worth mentioning that, after the disintegration of the Vienna Circle, its former members still occasionally made reference to the "scientific conception of the world" when speaking about general ideological questions. For example, Carnap spoke about "scientific humanism" as a view shared by the majority of the logical empiricists (Carnap 1963, 81ff.).

After the dissolution of the Vienna Circle, the forced migration of most of its members and the dispersion of the logical empiricist movement from its centers in Central Europe, the twin aims of a transformation of philosophy and the establishment of philosophy of science could only be envisaged once the ties to their previous cultural context and audience had been severed. But even in these difficult times the proponents of the exiled Vienna Circle organized six well-attended prestigious international conferences, "International Congresses for the Unity of Science": Paris (1935 and 1937), Copenhagen (1936), Cambridge, UK (1938), Cambridge, Massachusetts (1939), and Chicago (1941). One can thus say that the demise of the Vienna Circle in the German-speaking world was accompanied by the transformation of Viennese "Wissenschaftslogik" into philosophy of science in the Anglo-Saxon scientific community.

RECENT REASSESSMENTS
The new historiography on Logical Empiricism started with the rediscovery of Ernst Mach (1838-1916) as a precursor of Gestalt theory, evolutionary epistemology, (possibly radical) constructivism, and the modern historically oriented philosophy of science. Already in Mach's reception in the Vienna Circle one can see not only a certain pluralism of views but also a polarization of the various positions (Mach's influence on Carnap's Aufbau/Logical Structure [1967], the critical distancing to "psychologism" in the manifesto, the alternative to the principle of economy, etc.)

Even prior to World War I, the predecessor of the later Vienna Circle (the "First Vienna Circle") had begun to take shape both as an organization and as a philosophy (Uebel 2000). Within a discussion circle (inter alia, with Frank, Hahn, and Neurath) at a coffeehouse, traditional "academic philosophy" grew more scientific. This so-called "First Vienna Circle" met regularly as of 1907 to discuss the synthesis of empiricism and symbolic logic as modeled after Mach, Boltzmann and the French conventionalists (Pierre Duhem and Henri Poincaré) (see CONVENTIONALISM; DUHEM THESIS; POINCARÉ, HENRI). This was also seen as an indirect answer to Lenin's polemical remarks against Mach in his book, Materialism and Empirio-Criticism (1909), which remained very influential in Eastern Europe up to the Velvet Revolution of 1989-90.

This early phase in the development of logical empiricism can also be interpreted as an anti-Cartesian turn in epistemology and philosophy of science, which undermined both the synthetic a priori and the secure foundations of knowledge. In the middle of the permanent crisis of philosophy between reform and revolution in society and science, the further development of this "scientific philosophy" had, in any case, been initiated.

With the conflict-laden appointment of the physicist and philosopher Moritz Schlick (1882-1936) to Mach's chair for natural philosophy of the "inductive sciences" in Vienna in 1922, the heyday of scientific philosophizing in the post World War I period was prolonged. Even though Schlick felt committed to an epistemological realism in his main work, General Theory of Knowledge (1918/1925), he began his inaugural lecture with a programmatic allusion to Mach under the sway of the Viennese tradition up to Wittgenstein, that almost all philosophy is natural philosophy.

In the phase during which the Schlick Circle became a veritable institution, there was already a pluralism of positions that had emerged in the field of tension between Wittgenstein's Tractatus and Carnap's Logischer Aufbau der Welt/Logical Construction of the World (Carnap 1967). Yet notwithstanding all the discrepancies between Carnap's "rational reconstruction"and the philosophy of ideal language (Wittgenstein), all those involved came to identify with a philosophical reform movement as opposed to academic philosophy.

This radical program, in turn, left an indelible mark on avant-garde art (constructivism associated with Gerd Arntz, the artist of Neurath's pictorial language-see NEURATH, OTTO), literature as well as architecture (Werkbund and Bauhaus) centering around Ludwig Wittgenstein, Paul Engelmann, Adolf Loos, and Josef Frank, as well as in the context of Neurath's efforts within the Congrés International d'Architecture Moderne (Nemeth and Stadler 1996). Clarity and precision as ends in themselves and features of scientific philosophy bridged both Wittgenstein's cultural pessimism and the socio-culturally enlightened impetus of the modernist Vienna Circle.

With this convergence of various elements of philosophy of science, theoretical innovation was accelerated in the phase in which the Vienna Circle made public appearances and expanded its international contacts. The latter development was accompanied by the disintegration and uprooting of Logical Empiricism in the German-speaking world. In this sense, the phenomenon of the Vienna Circle is a prototypical case study on intellectual emigration (Stadler 2003b, c).

To all appearances, there seem to be two diametrically opposed trends. While the international influence of the Vienna Circle was steadily growing, the group had been systematically marginalized in Austria and Germany starting in the early 1930s. The murder of Schlick and the disgraceful, for the most part anti-Semitic, reactions to this, brutally ushered in the process which can be described as the "demise of scientific reason" (Stadler and Weibel 1995). This took place in parallel with the general trend at universities, which at the time were increasingly coming under the influence of a growing anti-democratic and racist discourse dominated by clerical-fascist and national socialist forces. This development led to the "Anschluss" which culminated in systematic dismissals, banishment, and annihilation of many leading intellectuals and others (Stadler 2002).

CONCLUDING REMARKS
Looking at the current definitions of the Vienna Circle, one can quickly recognize the difficulty of providing a representative description of the Circle and of logical empiricism in its entirety. Even the autobiographical accounts of Vienna Circle members since the classical period of the Schlick Circle show a remarkable variance - depending on focus and underlying motivations.

What these texts have in common is the refutation of metaphysics as well as of philosophy as a discipline in its own right. As an alternative, one finds a tendency towards a (physicalist) unified science that later culminated in an empiricist encyclopedia project and that includes the principle of tolerance as applied to logic and scientific languages. Here, the contours of epistemological options emerge. If one also takes into account that the manifesto represents only one variant of the Vienna Circle at the end of the 1920s, then it becomes amply clear that there existed only a limited consensus.

In addition, it is obvious that neither the autobiographical accounts of contemporaries nor the historical accounts originating shortly after 1945 were able to provide an adequate picture of the Vienna Circle. Moreover, there exists only a partial, albeit broad, overlap of the concept of Vienna Circle with that of logical empiricism in general when one takes into account the related movements of the Berlin Circle around Hans Reichenbach or the Warsaw Group around Alfred Tarski (Danneberg, Kamlah, and Schäfer 1994).

Is it still possible to find a sort of basic agreement here—one that unites the members of the Vienna Circle—both the central figures and those on the periphery? First of all, it is a way of philosophizing based on linguistic analysis and a great amount of problem-oriented, open-ended discussion. This was experienced personally by Arne Naess, who focused several times on the Vienna Circle's "thought style" which, in (not only) his opinion, leads to an inherent "pluralism of tenable worldviews" (Naess 2003). Second, the use of an unambiguous language, together with exact methods, is certainly a main legacy of the Circle and those associated with it. It is only when this exact formal approach is adopted that the content and positions can be constructively criticized and refuted—a characteristic which most current modern and postmodern philosophies lack.

The explicit and hidden history of the Vienna Circle from "Wissenschaftslogik" to the recent philosophy of science documents the wide range, pluralism, and diversity of the Viennese heritage and message. Be it called "scientific philosophy" (as initiated by Schlick), "scientific humanism" (according to Carnap), or a "republic of scholars" (following Neurath), it is a guide to an intellectual journey which continues through the present day and probably on into the future.

See also: ANALYTICITY; CARNAP, RUDOLF; CONVENTIONALISM; DEMARCATION; PROBLEM OF; EMPIRICISM; HAHN, HANS; HEMPEL, CARL GUSTAV; LOGICAL EMPIRICISM; MACH, ERNST; NEURATH, OTTO; PHENOMENALISM; POPPER, KARL; RATIONAL RECONSTRUCTION; QUINE, WILLARD VAN ORMAN; SCHLICK, MORITZ; UNITY AND DISUNITY OF SCIENCE; UNITY OF SCIENCE MOVEMENT; VERIFIABILITY.

References
Blumberg, Albert, and Feigl Herbert (1931) "Logical Positivism. A New Movement in European Philosophy" In Journal of Philosophy 28: 281-296.

Carnap, Rudolf, Hahn, Hans, and Neurath, Otto (1929) Wissenschaftliche Weltauffassung. Der Wiener Kreis. (1929) Hrsg. vom Verein Ernst Mach. Wien: Artur Wolf Verlag. Abridged English Translation as: "The Scientific Conception of the World: The Vienna Circle." In Neurath (1973), 299-318.

Carnap, Rudolf (1931) "Überwindung der Metaphysik durch logische Analyse der Sprache" In Erkenntnis 2: 219-241.

___(1934) Logische Syntax der Sprache. Wien: Springer. English Translation: The Logical Syntax of Language. London: Routledge 1937.

___(1963) "Intellectual Autobiography" In The Philosophy of Rudolf Carnap, 3-84, edited by Paul A. Schilpp, La Salle, Ill.: Open Court.

___(1967) The Logical Structure of the World. Berkeley and Los Angeles: University of California Press.

Danneberg, Lutz, Kamlah, Andreas, and Schäfer, Lothar (eds.) (1994) Reichenbach und die Berliner Gruppe. Braunschweig-Wiesbaden.

Frank, Philipp (1949) Modern Science and its Philosophy. Cambridge University Press.

Hardcastle, Gary, and Richardson, Alan W. (2003) (eds.) Logical Empiricism in North America. Minneapolis: University of Minnesota Press.

Heidelberger, Michael, and Stadler, Friedrich (eds.) (2003) Wissenschaftsphilosophie und Politik/Philosophy of Science and Politics. Wien-New York: Springer.

Hempel, Carl G. (1993) "Empiricism in the Vienna Circle and in the Berlin Society for Scientific Philosophy. Recollections and Reflections" In Stadler 1993: 1-10.

Kaufmann, Felix (1936) Methodenlehre der Sozialwissenschaften. Wien: Julius Springer. Reprint: Wien-New York: Springer 1999.

Kraft, Viktor (1950) Der Wiener Kreis. Der Ursprung des Neopositivismus. Wien-New York: Springer.

Menger, Karl (1979) Selected Papers in Logic and Foundations, Didactics, Economics. Dordrecht-Boston-London: Reidel.

___(1994) Reminiscences of the Vienna Circle and the Mathematical Colloquium. Edited by Louise Galland, Brian McGuinness, and Abe Sklar. Dordrecht-Boston-London: Kluwer.

Naess, Arne (2003) "Pluralism of Tenable Worldviews" In Stadler 2003a.

Nemeth, Elisabeth, and Stadler, Friedrich (eds.) (1996) Encyclopedia and Utopia. The Life and Work of Otto Neurath (1882-1945). Dordrecht-Boston-London: Kluwer.

Neurath, Otto, Carnap, Rudolf, and Morris, Charles (eds.) (1971) Foundations of the Unity of Science. Toward an International Encyclopedia of Unified Science. Volume I, Nos. 1-10, Volume II, Nos. 1-9. Chicago-London: Chicago University Press.

Neurath, Otto (1921) Anti-Spengler. München: Callwey. English in Neurath (1973), 158-213.

___(1931) Empirische Soziologie. Der wissenschaftliche Gehalt der Geschichte und Nationalökonomie. Wien: Springer. English in Neurath (1973), 319-421.

___(1946) "The Orchestration of the Sciences by the Encyclopedia of Logical Empiricism" In Philosophy and Phenomenological Research, VI/4, 496-508.

___(1973) Empiricism and Sociology. Edited by Marie Neurath and Robert S. Cohen. Dordrecht-Boston: Reidel.

Quine, Willard Van Orman (1953) From a Logical Point of View. 9 Logico-Philosophical Essays. Cambridge, Mass.: Harvard University Press.

Schlick, Moritz (1918/1925) General Theory of Knowledge. Translated by Albert E. Blumberg. Wien-New York: Springer 1974.

___ (1934) "Über das Fundament der Erkenntnis" In Erkenntnis 4: 79-99.

___(1950) "Moritz Schlick" In Philosophen-Lexikon. Ed. by Werner Ziegenfuss and Gertrud Jung. Berlin: de Gruyter.

Stadler, Friedrich (ed.) (1993) Scientific Philosophy: Origins and Developments. Dordrecht-Boston-London: Kluwer.

___(2001). The Vienna Circle. Studies in the Origins, Development, and Influence of Logical Empiricism. With the first publication of the protocols (1930-31) of the Vienna Circle and an interview with Sir Karl Popper (1991).Wien-New York: Springer.

___(2002) "The Emigration and Exile of Austrian Intellectuals." In Austria in the Twentieth Century, edited by Rolf Steininger, Günter Bischof, and Michael Gehler, 116-136. New Brunswick and London: Transaction Publishers.

___(ed.) (2003a) The Vienna Circle and Logical Empiricism. Reevaluation and Future Perspectives. Dordrecht-Boston-London: Kluwer.

___(2003b) "The 'Wiener Kreis' in Great Britain: Emigration and Interaction in the Philosophy of Science" In Timms/Hughes, 155-180.

___(2003c) "Transfer and Transformation of Logical Empiricism: Quantitative and Qualitative Aspects." In: Hardcastle/Richardson, 216-233.

Stadler, Friedrich, and Weibel, Peter (eds.) (1995) Vertreibung der Vernunft - The Cultural Exodus from Austria. Wien-New York: Springer.

Timms, Edward, and Hughes, Jon (eds.) (2003) Intellectual Migration and Cultural Transformation. Refugees from National Socialism in the English-speaking World. Wien-New York: Springer.

Uebel, Thomas E. (2000) Vernunftkritik und Wissenschaft. Otto Neurath und der Erste Wiener Kreis. Wien-New York: Springer.

von Mises, Richard (1951) Positivism. A Study in Human Understanding. New York: Dover.

Friedrich K. Stadler

The author thanks Camilla Nielson for this translation.

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