in its earlier stage and the Rgveda is full of relics of this stage of thought. Even the world polytheism is misapplied to such an early stage of the Vedic thought". What is Living and What is Dead in Indian Philosophy (1976) 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. The book also endeavours to demonstrate how Indian philosophy was not any exception to the sharp conflicts between idealism and materialism, which are universally evident in the philosophical traditions of other regions. Further, it considers the role of the law-givers like Manu in establishing the supremacy of the idealist traditions, and how due to the censor and censure anti-idealists like Varahamihira and Brahmagupta worked out their philosophies in distinctive Aesopian language, developing their own modes of camouflaging their ideas. Like elsewhere, in India too anti-idealists and materialists took practice as the main criterion of truth. Nyaya-Vaisheshikas were most outspoken in this regard, "after a knowledge is proved true in practice, there remains no doubt about the proof; hence the question of proving does not arise". On the other hand, the idealists believed in complete separation between theory and practice. They adhered to, in the words of Kumarila Bhatta, the principle of bahyartha-sunyatva (the unreality of the objects of knowledge), which, according to Debiprasad Chattopadhyaya, formed "the real pivot of idealism throughout its Indian career". Science and Society in Ancient India (1977) This book is about scientific method in ancient India and how societal divisions of the time shaped the development of science. Debiprasad Chattopadhyaya chooses the field of medicine for the purpose, because, according to him, "the only discipline that promises to be fully secular and contains clear potentials of the modern understanding of natural science is medicine". The main concentration of