First published in 1995. This study is intended as a contribution to the empirical study of religion, and in particular to the study of religious change. Using empirical method of using documents, interviews and experiments the author tests his old hypotheses in order to formulate new ones that my lead him to the truth. He focusses on the distinctions used throughout this book, that are between what people say they believe and say they do, and what they really believe and really do, using his research of the Sinhalese Buddhists in Ceylon