The purpose of this book is to describe and to give a theoretical explanation of the developments of Pay-As-You-Go (PAYG)-financed public pension schemes in democracies from a positive point of view. The book especially tries to grasp the determinants for changes in PAYG-systems. It is shown that if confidence in the continuation of an operative public pension scheme is growing, the conversion from a Capital-Reserve to the PAYG system - which has occurred in the history of most schemes - can be explained out of the self-interest of the generations alive. On the other hand, if a PAYG-system...