"Centesimus Annus" is a papal encyclical where the Pope explores and reaffirms the Catholic Church's teachings on social and economic issues. It was written on the hundredth anniversary of "Rerum Novarum," an earlier encyclical addressing issues of labor and the economy. The document discusses the dangers of both socialism and capitalism, and emphasizes the importance of a moral and ethical approach to economics, one that respects human dignity and prioritizes the common good above personal gain.

This book is a collection of the encyclicals issued by Pope John XXIII during his tenure as the head of the Catholic Church. The encyclicals, or papal letters, address a variety of topics including social justice, peace, human rights, and the role of the Church in the modern world. They provide insight into the Pope's theological and philosophical perspectives, as well as his vision for the Church and its mission in society.