A presentation of the basic models of the most important economic agents (households, firms, the banking system etc.). The influence of ethics on the decisions of persons is discussed within the context of mutual influences of one person on another. It is shown that this leads to a Markov chain which converges to a final situation which in many cases is independent of the initial conditions. The book helps the reader to understand the interdependence of humanities and economics and how to model this interdependence in economics.