In the landscape of physical science, Herbert Callen's seminal work, Thermodynamics and an Introduction to Thermostatistics , represents a paradigm shift from the historical, engine-centric development of thermodynamics toward a rigorous, axiomatic framework. Rather than deriving laws from steam engines and cycles, Callen reconstructs the entire field from a set of fundamental postulates centered on the concept of entropy. 1. The Postulatory Foundation
) of the extensive parameters that is maximized at equilibrium for any isolated system. Thermodynamics and an Introduction to Thermosta...
. This contrasts with empirical approaches that define temperature based on thermometry. In the landscape of physical science, Herbert Callen's
There exists a function (entropy,