The twelfth “book” of the Khuddakanikāya. It really belongs to the literature of the Abhidhamma type, and describes how analytical knowledge can be acquired by an Arahant. It presents a systematic exposition of certain important topics of Buddhism. It is possible that, before the development of the extant Abhidhamma Piṭaka, it passed as one of the Abhidhamma treatises.
The book consists of three chapters (vagga): Mahā Vagga, Yuganaddha Vagga, and Paññā Vagga. Each chapter contains ten topics (kathā).
The treatment of the various topics is essentially scholastic in character, and whole passages are taken verbatim from the Vinaya Piṭaka and from various collections of the Sutta Piṭaka, while a general acquaintance with the early Buddhist legends is assumed. (Published by the P.T.S. There is an index in J.R.A.S., 1908).
A commentary exists called the Saddhammappakāsinī, written by Mahānāma, a Thera of Sri Lanka.