In this monography there are presented and discussed the following categories of concepts: truth and causes, randomness, isomorphism, homomorphism, models, modelling, expectations, tools and effects of the use of monetary policy, potentia and calculus of potentias, theory and theorizing.

These categories make themes of successive chapters of this book. It seeks to provide both theoretical and empirical foundations for doing economic research by economists, econometricians, financiers, and management scientists who want to deepen their economic and methodological backgrounds.

The author presents the essence of the considered concepts from the point of view of the philosophy of science, logic, mathematics, economics and finance, as well as, empirical testing of models and theories.