Padarūpasiddhi

The Padarūpasiddhi, usually just the Rūpasiddhi — Kaccāyana's grammar taken apart and rearranged into a shape a student can work through.

Its date depends on an identification. The colophon gives the author as Buddhappiya, also called Dīpaṃkara. If he is the same man who wrote the Pajjamadhu — also in this collection — the work belongs to the second half of the 1200s CE; if not, it has no date. The Pali catalogue gives the Rūpasiddhi, its ṭīkā and a third work to a teacher named Dīpaṃkara.

Norman sets it beside Medhaṃkara's Payogasiddhi in a neat symmetry: the one stands to Kaccāyana's grammar as the other stands to Moggallāna's. Kaccāyana's is the earliest Pali grammar we have, and almost nothing is known about it. He must be later than Buddhaghosa, who never refers to him; if he used the Kāsikā he is later than the 600s CE, but that evidence is disputed — so the honest statement of his date is after Buddhaghosa, possibly after 600 CE, with no upper limit. Nothing is known of the man but his name, and he seems unconnected with any other Kaccāyana known from Sanskrit or Pali. His work owes much to Pāṇini and to the Kātantra.