This mini volume was first published in 1923. Buddhism is often associated with non-theism, as it does not place significant emphasis on a Supreme Being or the existence of Heaven and Hell. The concept of spirits, or preta (Pali: petta), and their role in the Buddhist religious tradition is a fascinating subject. Many materials from the Hinayana Buddhist tradition, such as Paramatthapadīpanī, the commentary on Petavatthu (part of the Khuddaka Nikāya), and the Jātakas, provide valuable insights into this area. This book makes a significant contribution to understanding the role of spirits, the spirit world (pretaloka), and the practice of ancestor offerings in Buddhism. The author explores the concept of preta in classical Buddhism and the belief systems surrounding it. Various forms and types of pretas, along with the stories and doctrinal implications of the spirit world, are thoroughly examined in this work. About the Author Bimala Churn Law (1892-1969) was an Indologist and a research fellow at the Royal Asiatic Society. He authored books on Buddhism, Jainism, and the geographical history of India. In 1935, he established the Dr. B.C. Law Trust Fund at the Royal Asiatic Society.