The monograph offered to the attention of readers is the second in the series devoted to the development of probabilistic economic theory. This book presents principles of physical economics, new economic discipline primarily concerned in the book with the agent-based physical modeling of the market economic systems and eventually with the elaborating of probabilistic economic theory. At the heart of physical economics and probabilistic economic theory are the well-known cornerstone concepts of classical economics, in particular the subjective theory of value, such as regularity in the sequence of market phenomena and an interdependence of those, as well as key roles of individuals’ actions and social cooperation in the many-agent market processes. This monograph may seem interesting to everyone who is engaged in research in economics, finance, econophysics or physical economics, as well as to professional investors and stock traders.