A Single Axiom for Classical Thermodynamics

The definitions employed in classical thermodynamics are revised and a single axiom is stated from which all the relations of classical thermodynamics can be deduced. A detailed discussion of the meaning of the terms, system, possible variation, equilibrium, and thermodynamic system is followed by a statement of the axiom of stable equilibrium. The zeroth, first, and second laws and the state principle are then derived as theorems. Unambiguous definitions of heat, work, and temperature are deduced. The objective is to avoid the redundancies and implied hypotheses that may be found in previous treatments and to provide a rigorous and unambiguous base for exposition of all the classical aspects and the recent developments of thermodynamics.