Abstract

It is commonly thought that Jean Perrin argued for the reality of atoms in the early twentieth century by using what Wesley Salmon calls a “common cause” argument, also known as robustness reasoning. After citing some concerns with this interpretation of Perrin, I offer a different interpretation of Perrin’s work that more closely depicts the details of Perrin’s reasoning in his relevant published writings. I then offer a historical argument that supports this interpretation and discuss the philosophical merits of Perrin’s style of reasoning as I have presented it. I close by showing how my interpretation is distinct from previous interpretations of Perrin’s work.