A Philosopher against the Bandwagon: Carnap and the Informationalization of Thermal Physics

In this article I aim to demonstrate that Rudolf Carnap’s analysis of the application of information theory within physics, an analysis that is an intellectual-historical precedent of current philosophical criticisms of the information theoretical tendency, is justified. First, Carnap and Bar-Hillel underlined the unjustified ‘semantification’ of Shannon entropy. Furthermore, Carnap criticized the ‘physicalization’ of Shannon entropy, but that criticism was not accepted by the physics community of the 1950s. Finally, in the posthumously published Two Essays on Entropy, Carnap developed a critical assessment of entropy concepts that showed deep conceptual and interpretative deficiencies in Jaynes’s and Brillouin’s informational approaches to thermophysics.