Reorganizing Physical Knowledge through Philosophical Reflection

Reorganizing Physical Knowledge through Philosophical Reflection

Olaf Engler, Jürgen Renn

Cooperation Partners: 

Moritz Schlick Gesamtausgabe, University of Rostock


The bolded passage from the manuscript reads: ”The psychic phenomena are
non-spatial, yet for us, spatial relations obviously provide the only ­possibility of measurement. All measurements occur in such a way that spatial ­coincidences ­(readings on a galvanometer, the positions of the hands of a clock etc.) are ­observed.” (Moritz Schlick’s Nachlass, Inv.-Nr. A. 97-1. p. 9, reverse side)

Specific studies are focusing on the fruitful interaction between the philosophy of science and the development of modern physics at the beginning of the twentieth century, with a particular focus on the discussions between Albert Einstein and Moritz Schlick on the physical interpretation of the emerging theory of general relativity.

A crucial aspect of the history of general relativity was Einstein’s formulation and eventual rejection of the famous hole argument. While the hole argument initially seemed to suggest that generally covariant theories of gravitation are impossible, its later rejection opened up new insights into the nature of space and time, and in particular their dependence on dynamical fields. In contrast to the accepted view, it could be shown that Moritz Schlick’s principle of spatio-temporal coincidences played the decisive role in Einstein’s overcoming of the hole argument. This principle is first documented in a text from Moritz Schlick’s estate from 1910.

In the context of general relativity, Schlick’s principle implies that only point coincidences constitute measurable entities in physics. Einstein’s acceptance of this principle was closely related to his reading of Hume and the formative role of Hume’s epistemology for the formulation of special relativity. On an epistemological level, it furthermore complemented, from Einstein’s perspective, the role that Mach’s principle long played as an ontological underpinning of his new theory of gravitation, giving primacy to material events over the structures of space and time. The coincidence principle thus unfolded a vast integrative potential linking different dimensions of knowledge and establishing criteria for the aspects of physical reality reflected by the new theory. Its further implications are also pursued in the context of the ongoing research on the history of quantum gravity.