 susceptible to a mechanical explanation. In our view Poincaré develops the appropriate epistemological and methodological details of this view of the nature of physical theory: a pragmatist/conventionalist view. Duhem proposes to disenfranchise Poincaré's generalization of the consequences of his critical analysis of this method applied in mechanical theory to physics in general. This generalization would be legitimate if mechanical theory were the unifying framework for the whole of physics, or if it were based on purely mathematical terms. Duhem questions Poincaré's view because it is based upon strategies appropriate to mechanical theories and not to theoretical physics such as mathematical physics. Maxwell's methodological viewpoint on the mechanistic program (like many of his contemporaries') uncritically presupposes a generalized thesis about the relation between Lagrange's formulation of mechanics and the mechanical interpretation of physical phenomena. This thesis identifies the Lagrangian method with the mechanical interpretation of physical phenomena, constituting the main methodological principle of the analytical approach to mechanical explanation. Duhem begins his critical examination of the analytic approach to mechanical theory by questioning this identification, and in particular its sufficient condition. Duhem separates the mathematical structure of Lagrange's method from its mechanical interpretation (Chiappin 1989, 62-68). The mechanical interpretation is, for him, one of the many possible interpretations of the Lagrangian system of equations and generalized coordinates. His criticism illuminates the generality of the mathematical formulation of Lagrangian mechanics by pointing out that its applications go beyond the application in mechanical theory (for example, Maxwell's use of it to organize his electromagnetism theory). The axiomatization of thermodynamics by Gibbs was based upon thermodynamical potential instead of Carnot's cycle. The model of this axiomatization of thermodynamics is t