The Enigma of the Aerofoil: Rival Theories in Aerodynamics, 1909–1930, Chicago 2011; Wittgenstein on Rules and Institutions, London 1997; Wittgenstein: A Social Theory of Knowledge, Hampshire 1983; Knowledge and Social Imagery, London 1976.
Both the philosopher Karl Popper and the physicist Philipp Frank had close personal connections with Vienna and were responsive to the political forces that impinged on its cultural life. By the late 1930s both had left central Europe and both had engaged with the topic of relativism. Both found the theme of relativism to be important for their work on scientific methodology and for exploring the relation of scientific knowledge to its social context. David Bloor uncovers the traces of the relativism debates.