The primary strand is the Austrian school of economics and social thought that can be traced from Carl Menger, through Ludwig von Mises and Friedrich Hayek to the more recent leadership of Ludwig Lachmann and Israel Kirzner and their contemporary followers.
The second strand is the contribution of Karl Popper who was Austrian by birth but had little connection with the economists apart from his friendship with Hayek.
The third strand can be traced to Franz Brentano and Alexis Meinong. It developed in different directions, as it was taken up by Russell and Moore in Cambridge, by Roderick Chisholm in the US, by Husserl (to Heidegger) and it also appeared in the form of Popper's "third world" of objective knowledge.
The project began with an Agricultural Science degree, with a view to working with the FAO to address the problem of World Hunger. By the time the degree was finished it turned out that the root of the problem was not growing the food but a complex of social and political factors. Before I left Agriculture my thesis supervisor lent me The Poverty of Historicism and The Open Society and its Enemies which kicked off a lasting interest in most of Popper's work (leaving out quantum physics and probability theory).
ANOTHER FALSE START
The project shifted to Sociology which turned out to be a false move (as von Mises would have warned). Something of value (not fully realised at the time) was heavy reading of Talcott Parsons, although nobody in the school was interested in his ideas. Later on it became apparent that up to 1937 (his first book) Parsons was converging on the same point where Mises and Popper were heading but that meeting of minds never happened due to the war and other factors
POPPER AND THE AUSTRIANS - the More Austrian Program
The project did not progres very much further until the early 1980s when two happy accidents events came about. The first was the appearance of the three volumes of Popper's Postscript to The Logic of Scientific Discovery which revitalised my interest in his philosophy, fortified by the theory of metaphysical research programs, Like the best wine, he kept that for the end of the party - the Metaphysical Epilogue to the third volume of the Postscript. Second, the Austrian school of economics came into view and economics made sense for the first time.
It soon became apparent that the work of the Austrian economists would be better understood as a metaphysical research program, moreover a program that fits like a glove with Popper's metaphysics, his methodology, his epistemology and his non-socialist liberalism. This is not music to the ears of most Popperians who are not at home with the Austrian economists (or minimum state liberalism) nor to most of the Austrians, especially the hard core Miseans.
Some important figures to mention in connection with the More Austrian Program are Larry Boland and Jack Birner. Boland in a 1982 contribution suggested four agenda items for a “Popper-Hayek” program of individualistic explanation of dynamic processes. 1, Anti-justificationism. 2, Anti-psychologism. 3, Rational decision-making, according to the “logic of the situation”. 4, Situational dynamics - behavior can change as a result of learning as well as from changes in the situation.
Jack Birner is also outstanding in his exegesis of Popper and Menger.
Another recent player in this game is Ivo A Sarjanovic who has a paper Popper y los Austriacos: atando cabos in press in Argentina.
The AUSTRIAN PHILOSOPHERS - The Even More Austrian Program
Enter Brentano and friends. This strand is the lesser-known Austrian school of philosophy which near the turn of the twentieth century became is the precursor of several developments, some of which appear to be at odds with each other. The relationship of this strand to the economists was not apparent until quite recently because the best-known school of philosophy from Austria was the Logical Positivism of the Vienna Circle (which became logical empiricism in the US) and this school of thought was anathema to the Austrian economists.
Barry Smith made a significant contribution to the exegesis of Austrian philosophy and the Aristotelian foundations of Austrian economics before he moved on to explore aspects of ontology applied to a wide range of medical and biological problems and issues, especially information storage and retrieval.
He contributed a paper on "Aristotle, Menger, Mises: and essay in the metaphysics of economics" to a collection edited by Bruce Caldwell called "Carl Menger and his legacy in economics" published as a supplement to "History of Political Economy" in 1990.
The "Austrian Aristotelianism" that Smith spells out in this paper is almost identical to the program that emerged many years later from Popper's critique of positivism, and especially from his critique of determinism, subjectivism and instrumentalism in quantum physics. Smith sums up the Aristotelian program with seven general points and some extra points applied especially to the social sciences.
1. The world exists, independently of our thinking and reasoning activities.
2. There are in the world certain simple `essences' or `natures' or `elements', as well as laws, structures or connections governing these, all of which are strictly universal.
5. We can know, albeit under the conditions set out in 4., what the world is like, at least in its broad outlines, both via common sense and via scientific method. ,
6. We can know what this world is like, at least in principle, from the detached perspective of an ideal scientific observer.
7. The simple essences or natures pertaining to the various different segments or levels of reality constitute an alphabet of structural parts.
8. The theory of value is to be built up exclusively on `subjective' foundations, which is to say exclusively on the basis of the corresponding mental acts and states of human subjects.
9. There are no `social wholes' or `social organisms'.
10. There are no (graspable) laws of historical development.
A later book explored in depth the ramifications of some Araistotelian/Austrian ideas into various strands of philosophy, literary theory, psycholgy (especially the gestalt movement) and Austrian economics. He advance the important concept of "fallible apriorism" which treats apriorism as a methodology and not a method of proof or justification.