BOOK REVIEW 85 reach man only in the shape of a faint indirect echo is precisely religiosity. In this sense I am religious. The cosmic religious experience ... cannot lead to a definite conception of God or to a theology." He gave the name "cosmic religious feeling" to his deep conviction in the "rationality of the universe". Henry Le Roy Finch, in Conversation with Einstein, summed up Einstein's religion as "Truth, independent of man, independent of consciousness, independent of sense experience, independent of morality —this was Einseein's religion." For Einstein "the need to know' and the 'need to believe' were not counterposed. He viewed them as complementary in the sense that the 'need to believe' always provided greater, impetus for ^need to know5. It is this deep conviction that led Einstein to adopt the attitude that he did to the development of quantum theory—it was not a theory of principle. Recognising the success of the theory he yet held to a belief "in the possibility of giving a model of reality which shall represent events themselves and not merely the probability o,f their occurrence." Pais has worked on this monumental biography of Einstein with tremendous erudition and sensibility. It is a delight to read the book with its details, personal and scientific. In our turbulent times when a nuclear holocaust is a distinct possibility and more than ever before irrationalism and anarchy of thought have become a fashionable trend, reading about a man who not only by his scientific endeavour but also by his human concerns showed tremendous courage in upholding the ideals of rationality, peace and the progress of human cognition and civilisation, is a rewarding and reinforcing experience. RAJENDRA PRASAD Editorial Office, People's Democracy, New Delhi.