The aim of this paper is to give a self-reflective account of the building of Galileo's pendulum in order to discover what were the practical contingencies of building and using the pendulum for demonstrating the law of isochronism. In doing this, the unique Lebenswelt structures of Galilean physics are explicated through the ethnomethodological concepts developed by Harold Garfinkel. The presupposition is that the practical logic of Galilean physics is embedded in the instruments themselves. In building the pendulum and recovering its (...) original use, Galilean physics becomes for ethnomethodologists a first-hand practical discovery. This is not a reconstruction of the mind of the historical Galileo but, rather, an explication of Galileo's practical perspective on the instrument as an intersubjective and interchangeable standpoint available for ethnomethodological analysis. This enables us to study historical facts from the standpoint of the practical logic of the original practice with a pedagogical eye for the instructive reproducibility of science. (shrink)

This paper offers an ethnomethodological clarification of Husserl's concepts of Galilean physics and regressive inquiry. It employs the reader's textual-practical operationalization of these concepts. With the use of a simple optical prism as a perspicuous case of a scientific instrument, the reader will be asked and instructed to make a self-reflexive inquiry into the practical contingencies of the prismatic field of reflection. The reader will discover that the geometric structures of the reflective field of the prism is an achievement and (...) formalization of the reader's own operatlonalizations. I named these discoverable discovering operationspraxioms or practical axioms — the pre-scientific contingencies of the geometric structures of prismatic reflection. (shrink)