Sarvadarshanasangraha 7.81

7.81

iti śrūyate/ tat katham anyathā kathyate/ addhā/ ata eva ca tatrabhavatā rāmakaṇṭhena tat sūtraṃ triṃśattattvaparatayā vyākhyāyīty alam atiprapañcena/

How, then, can any different account be maintained? We grant this, and hence the venerable Rāma Kaṇṭha has explained that sūtra in its literal meaning [i. e., as puryaṣṭaka, is derived from aṣṭa, "eight"], so why should we be prolix in the discussion? Still, if you ask how we can reconcile our account with the strict nominal definition of puryaṣṭaka, we reply that there is really no contradiction, as we maintain that it is composed of a set of eight in the following manner:—(1.) The five elements; (2.) the five rudiments; (3.) the five organs of knowledge; (4.) those of action; (5.) the fourfold internal organ; (6.) their instrument;[30] (7.) nature [prakṛti]; and (8.) the class composed of the five, beginning with kalā, which form a kind of case.[31]