Neurath and Popper were closer to each other than to other Vienna Circle members

Evidence

Paradoxically, Neurath and Popper were much closer to each other than to some other Circle members. Both embraced a revised conventionalism, combining anti-absolutism and non-foundationalism, which discarded the view that scientific knowledge “corresponded” to reality. More importantly, Popper renounced any psychological foundation for knowledge, something which later became important for Hayek’s own rupture with Mises’s a priori praxeology of human action. In the cases of both Hayek and Popper, the distance they took from their initial intellectual environments entailed an epistemological argument that science could not rely on either deductive apodictic structures nor empirically derived protocols to guarantee its validity. Instead, they reckoned that truth corresponded to the result of an intersubjective process—thereby “socializing epistemology.” The heuristics of this process depended on three interrelated provisions: the methodology employed for discovery and justification, the design of its institutions, and the values shared by the participants. In the end, the epistemological conditions of truth and of social order ultimately shared the same foundations: that of conventional rules which could be revised and improved according to an established method. — Dieter Plehwe, Quinn Slobodian & Philip Mirowski (eds.), Nine Lives of Neoliberalism, 61

Categorization

• XREF: The claim that truth and social order share conventional-rule foundations is a pivot toward Hayek’s own epistemology and the later neoliberal synthesis, a through-line to other chapters in this book.
• DEFINE: Defines ‘revised conventionalism’ and ‘socializing epistemology’ as distinct from both logical empiricism and a priori praxeology.