In the Preface, Debiprasad Chattopadhyaya says his purpose in this book is to present "an analysis of our philosophical traditions from the standpoint of our present philosophical requirements. These requirements, as understood here, are secularism, rationalism and science-orientation". He once again finds the philosophical development – debates and clashes – in ancient India embedded in the class struggles of the time. He discusses the materialist foundation of Vedic rituals, which he finds similar to the magical belief of controlling the natural forces through yajnas, etc. He shows how these rites and rituals that evolved as primitive scientific endeavours were transformed into superstitions and monopolies in the hands of the oppressors with the advent of class divisions.