Unlike his rationalist brother Ludwig von Mises, Richard von Mises had strong empiricist leanings, which found expression in his frequency interpretation of probability and his qualified endorsement of logical positivism (or logical empiricism). His Kleines Lehrbuch des Positivismus was published in 1939 and translated and revised in English in 1956 as Positivism: A Study in Human Understanding and carried the following subtitle, “How the aims and attitudes of science apply to all the intellectual endeavors of mankind – whether in science, the arts, or ethics.” Sadly, the last edition of the book was published in 1968 and has long been out of print, a fate which sets him apart from other major 20th century empiricists such as Rudolf Carnap, Hans Reichenbach, and Alfred J. Ayer, whose major expositions of their views are still in print. The preface of the English edition of Positivism closes with a remembrance of Otto Neurath, one of the co-authors of the original Vienna Circle statement, The Scientific Conception of the World: The Vienna Circle, and one of the most passionate advocates of empiricism and the unity of the sciences.
Contrary to popular opinion, 20th century empiricism was not a rigid set of beliefs, and many of the original logical empiricists kept revising their views in response to the reception of their work and further investigations. What united the original logical positivists was an unwavering commitment to empiricism and a firm rejection of dualism in the scientific method. In a sense, one could argue that many of the core beliefs of the Vienna Circle have become so accepted among many scientific practitioners that there is no longer a need to argue for them. On the other hand, the worldviews of public opinion makers and public officials are still largely shaped by modes of thought and superstitions that have remained fairly immune to the rise of the experimental method and the rejection of metaphysics. In the case of politics, there is little reason to be surprised about this, because politics encourages irrational thinking, conformism, and atavism. Interestingly, Richard von Mises also offers his views on economic methodology and political economy and it will be rewarding to return to these views at the end of this review.
Positivism starts with a discussion of language. According to von Mises, many philosophical mistakes reflect misunderstandings about the function and limitations of language. He writes, “many problems of school philosophy are of this type: expressions, referring in ordinary language to a very vague and varying content of experience, are supposed to have some “objective” meaning and then attempts are made to “disclose” this meaning by kind of a definition.” For example, there is no God-given definition of the word “rationality.” But when a group of academics (such as economists) converge on the use of the word, it is a misunderstanding of the function of language to insist on a different definition of the word because its current use is “wrong.” Of course, when science evolves there is often a recognition that the original language is too crude and finer distinctions are being introduced to replace the older vocabulary. One of the defining characteristics of positivist philosophy is clarification of the use and abuse of language.
Like most authors in the positivist tradition, von Mises is interested in the question of what distinguishes true, false, and meaningless statements. He rejects the idea (which he attributes to Rudolf Carnap) that statements that do not satisfy the rules of logical grammar should be considered “meaningless” because it is not “possible to anticipate the rules of language in any exhaustive manner before knowing the sentences that will have to be tested by them in order to decide their admissibility or inadmissibility.” As an alternative, von Mises proposes the concept of “connectibility.” A sentence is connectible if it is compatible with a system of statements that regulate the use of language in that system. The statements of metaphysics, at best, only connect to each other in a very narrow range (they do not connect to the rules of formal logic, the natural sciences, ordinary language, etc.) and are of little practical use. Using this concept of connectibility makes it possibles to characterize the movement for a “unified science” in terms of connectibility of all scientific statements. Positivism concerns itself largely with the exposition of the concept of connectibility.
Von Mises then devotes two chapters to Mach’s elements and protocol sentences. Despite his own admission that “it is utopic to think that, starting from a given complex of element sentences, one could, by carefully following all the syntactic rules, arrive at an “encyclopedia of the sciences” which could command a validity of higher rank than that possessed by any of the existing individual sciences” he seems quite occupied with identifying the nature and structure of such element sentences. Instead of looking for such an Archimedean point it might be more practical to decide in favor of the language of the sciences that have been successful in understanding and predicting the observable world. Statements of chemistry can be reduced to statements in physics, statements in biology can be reduced to statements in (bio)chemistry, statements about behavior and psychology can be reduced to statements in biology etc. The remaining (social) sciences contain either statements that are of little descriptive or predictive value, or contain statements that have been successful in understanding and predicting human behavior but still cannot be connected to the statements of the exact sciences. The use of game theory in both the biological and economical sciences is a good example of an attempt to bridge that gap. As von Mises himself notes, “All we can attempt to do is by analysis and continuous criticism of linguistic usage to further the connectibility.”
In the chapter about probability, von Mises introduces his frequency interpretation of probability and distinguishes it from the use of probability in ordinary language and alternative conceptions of probability (subjective probability, logical probability). In this chapter, von Mises is quite insistent upon the view that an exact theory of probability can only refer to mass phenomena and repetitive events. It does not make sense to use the probability calculus for future unique events or single cases probabilities. He takes issue with attempts of logical empiricists like Hans Reichenbach and Rudolf Carnap to apply probability far beyond its range of validity. Considering the generally hostile attitude of Austrian economists towards positivism and empiricism, it is interesting to note that prominent Austrian economists who work in the Misesean tradition have endorsed Richard von Mises’ strict frequency interpretation of probability. In an article called The Correct Theory of Probability Murray Rothbard writes:
“While probability theory is generally thought of as a branch of mathematics, its foundations are purely philosophic, and Richard von Mises, in his great work Probability, Statistics, and Truth, developed the correct, objective, or “frequency” theory of probability….if one holds to the objective Mises theory, it is unscientific and illegitimate to apply probability theory to any situations where the events (like the tossing of a die) are not strictly homogenous, and repeated a large number of times. And since, outside of die tossing or roulette, all the events of human action, economic or political or in daily life are clearly not homogeneous and therefore not repeatable, the Mises view demonstrates that all use of probability theory in social science is illegitimate.”
Along the same lines, Hans-Hermann Hoppe writes approvingly that for Ludwig von Mises “there is no such thing as a priori probability. Nor is there such a thing as the probability of a singular event. Probability statements refer to “objective” probabilities of collectives (classes). They are based on empirical observations. And they are corrigible by such observations.” Whether the positions of Mises, Rothbard and Hoppe constitute a partial endorsement of positivism in case of the probability is a complicated matter because it is not unambiguously clear what the proper empiricist interpretation of probability should be, and in this chapter Richard von Mises is too partial to his own views (and too dismissive of the works of other empiricists) to offer a more systematic treatment of the question of the relationship between probability and his general positivist outlook.
In the chapters about deterministic physics, statistical physics, and miracles von Mises argues quite persuasively that positivism should not be identified with a set of dogmatic prohibitions or should rule out certain observations about reality when they do not conform with materialism or a deterministic outlook. What we should require from extraordinary statements (or miracles) is that they are subjected to the same kind of scientific investigation and corroboration as we expect from other claims to knowledge. This approach harks back to von Mises’s concept of “connectibility.” His open mindedness in this chapter is reminiscent of a statement by Rudolf Carnap in his seminal article Empiricism, Semantics, and Ontology (1950):
The acceptance or rejection of abstract linguistic forms, just as the acceptance or rejection of any other linguistic forms in any branch of science, will finally be decided by their efficiency as instruments, the ratio of the results achieved to the amount and complexity of the efforts required. To decree dogmatic prohibitions of certain linguistic forms instead of testing them by their success or failure in practical use, is worse than futile; it is positively harmful because it may obstruct scientific progress.
Perhaps the most interesting chapters in Positivism deal with his positivist outlook on the social sciences and ethics. Von Mises rejects methodological dualism; the idea that the approach and methods that are used in the physical sciences are inappropriate for the sciences that study man: “We find in all fields a progression from single observations to comprehensive generalization which corresponds to the essence of scientific work…”. As other logical positivists writing in the same period, von Mises recognized that one day human action could be analyzed and explained by “organic processes,” but the rather premature state of fields like neuroscience in his age prevented von Mises from stating his position much more strongly than is possible now.
Today, when we compare the progress in fields that study man from a biological perspective with fields that claim a unique approach for the humanities, it is clear that the case for dualism has further weakened. Humans are not exempt from the laws of physics and disciplines that recognize that fact clearly such as biochemistry, evolutionary biology, and neuroscience, have made significant progress in understanding man. Von Mises notes that progress in the study of man is slower because of “retardations due to organized prejudices.” In many places in the world (including the United States) evolution is still widely contested and it is only quite recently that scholars who approach human psychology from an evolutionary perspective are no longer meeting major obstacles to disseminating their work.
Richard von Mises has a distinctly different perspective on social science and economics than his brother Ludwig von Mises. He has little patience for the idea that economic theories are not subject to empirical testing: “mental reconstructions of observed facts must be tested to determine how far their consequences agree with continued observations.” Similarly, he does not reject the use of mathematics in economics and actually credits mathematical economics for offering “promising starting points for a rational treatment of economic problems.” In particular, von Mises praises John von Neumann and O. Morgenstern for introducing strategic behavior and expectations into economic theory. New classical economists like Robert Lucas, Jr., later recognized that expectations cannot be ignored in macroeconomics either.
Von Mises closes his book with a number of chapters on morals, law, and religion. Not surprisingly, von Mises states that “…in spite of centuries of endeavor one has so far not been successful in demonstrating any substantial ethical theorems that would enjoy unanimous recognition; and there is no hope that the goal of a “normative” ethic will be reached in in the future.” He argues against the idea that reason can discover objective normative rules and highlights the conventional and pragmatic nature of morals. There is little in these chapters that could not have been written by contemporary authors. He ends his book by situating his perspective in the broader empiricist tradition and with a succinct summary of his own perspective.
It is fair to say that this book cannot compare with the rigorous writings of scholars like Rudolf Carnap or Hans Reichenbach, but it is doubtful that he aimed at such a work. His book is basically a plea for the scientific view of the world and how this approach applies to various topics. As such, his basic outlook on knowledge deserves study and recognition.
Richard von Mises has now been largely forgotten as a writer about knowledge but his general outlook is still alive. For example, despite the fact that the writings of his brother have seen multiple editions and reprints, there is a broad consensus that economics, or any social science, should be conducted as an empirical science. On matters of morality, serious scholars have become more interested in the evolutionary, psychological and social sources of moral conduct than the futile search for categorical imperatives. Most of all, much progress has been made in connecting the physical sciences and the humanities through modern evolutionary biology. In this sense, Richard’s perspective has clearly prevailed, albeit not to the degree that he would have preferred.