Subordination and Bayes' theorem in the thermodynamics of composite systems

A completely new derivation of the probability distribution in energy of a small component of a composite system, which was previously derived from the composition law of the structure function and Boltzmann's principle, is given by the method of subordination in which the conjugate, intensive parameter is randomized and is shown to possess a Bayes distribution. The derivation allows an extension of the class of structure functions to include strictly stable laws which possess domains of attraction like the normal law