Changing concepts of causality in twentieth century physics

In recent years, causality has become a thriving research area in philosophy of science, and there has been a revival of interest in the metaphysics of causation. However, the consensus among philosophers of science is that causality has no role in fundamental physics. This consensus has only recently been challenged by Mathias Frisch. In this literature, references are made to the rich history of causality in science; however, no systematic investigation has yet been made of how conceptions of causality have changed over the past century as a result of developments in physics. This project examines the changes that conceptions of causality have undergone in the context of the development of quantum mechanics. In this way, it aims at a clarification of current debates on causality and at a reappraisal of the role of causal reasoning in physics. A hypothesis of the project is that contrary to what is often thought, in the period around the development of quantum mechanics (circa 1920-1940), few (if any) authors wanted to give up all aspects of causality in physics. Rather, there was a process of more precise articulation of different conceptions of causality; the history of science shows that conceptions of causality are continuously transformed, while causal reasoning has continued to play a role. The project aims furthermore to contribute to the literature on Kantian approaches in philosophy of science. In recent years, Michael Friedman`s approach to philosophy of science based on relativized a priori principles has attracted much attention. It has especially been discussed in the context of the philosophical implications of relativity theory. Given the fact that quantum mechanics was developed in roughly the same period as relativity theory and is connected to fundamental changes in the role of a priori principles of causality in physics, it would be of interest to see how this relates to Friedman`s work. A leading idea behind the project is that much clarification of the history of quantum mechanics and its philosophical impact can be gained by carefully distinguishing the different notions which are encompassed in the terms `causality` and `causation`. In the current literature on developments in early twentieth century physics, such a conceptual analysis of causality is lacking. Moreover, the project is based on the idea that to understand the transformations of causality in the early twentieth century, one has to study the work of both physicists and philosophers, and that there was more interaction between them than is usually acknowledged: during this period, many physicists had an active interest in philosophical developments such as (neo- )Kantianism and logical empiricism, while philosophers such as Schlick, Reichenbach and Frank aimed to develop an understanding of causality in terms of physics.