The object of this course of seminar lectures is to develop briefly one simple unified standard method, capable of dealing with every new problem that may arise.

1. General introduction; 2. The method of the most probable distribution; 3. Discussion of the Nernst theorem; 4. Examples on the second section; 5. Fluctuations' 6. The method of mean values; 7. The n-particle problem; 8. Evaluation of the formulae; 9. The problem of radiation; Appendix.