The Abhidhamma Pitaka, or the Philosophical Collection, forms the third great section of the Buddhist Pali Canon (Tipitaka). In its most characteristic parts it is a system of classifications, analytical enumerations and definitions, with no discursive treatment of the subject matter. In particular its two important books, the Dhammasangani and the Patthana, have the appearance of huge collections of systematically arranged tabulations, accompanied by definitions of the terms used in the tables. This, one would expect, is a type of literature scarcely likely to gain much popular appreciation, yet there is the fact that the Abhidhamma was, and is, highly esteemed and even venerated in the countries of Theravada Buddhism.
Two examples taken from the chronicles of Ceylon illustrate that high regard for the Abhidhamma. In the 10th century A.C. on the order of king Kassapa V of Ceylon, the whole Abhidhamma Pitaka was inscribed on gold plates, and the first of these books, the Dhammasangani, was set with jewels. When the work was completed, the precious manuscripts were taken in a huge procession to a beautiful monastery and deposited there. Another king of Ceylon, Vijaya Bahu (11th century), used to study the Dhammasangani in the early morning before he took up his royal duties, and he prepared a translation of it into Sinhalese, which however has not been preserved.
What were the reasons for such an extraordinary esteem for material that appears at first glance to consist of no more than dry and unattractive text books? And what actual importance do the two basic works of the Abhidhamma in particular, the Dhammasangani and the Patthana, still have today? These are the questions that we shall attempt to answer here.
In considering the reasons for this high esteem and regard for the Abhidhamma, we may leave aside any manifestation of faith, more or less unquestioning, that evokes in the devotee a certain awe owing to the very abstruseness and bulk of these books. That apart, we may find a first explanation in the immediate impression on susceptible minds that they are faced here by a gigantic edifice of penetrative insight, which in its foundations and its lay-out cannot well be ascribed to a lesser mind than that of a Buddha; and this first impression will find growing confirmation in the gradual process of comprehending these teachings.
According to the Theravada tradition the Abhidhamma is the domain proper of the Buddhas (Buddha-visaya), and its initial conception in the Master’s mind (manasa desana), according to the Atthasalini, is traced to the time immediately after the Great Enlightenment. It was in the fourth of the seven weeks spent by the Master in the environ of the Bodhi tree that the Abhidhamma was conceived. These seven days were called by the teachers of old ‘The Week of the House of Gems (ratana-ghara-sattaha)’. ‘The House of Gems’ is indeed a very befitting expression for the crystal-clear edifice of Abhidhamma-thought in which the Buddha dwelt during that period.