Pāṇini, whose date falls doubtless before 300 B.C., alludes in his grammar to the Naṭasūtras, books of rules for Naṭas, compiled by Çilālin and Kṛçāçva, and Professor Hillebrandt [597] has suggested that we should recognize in these works the earliest text-books of the Indian drama. But we have no other suggestion that Pāṇini knew of dramatic performances, and the only legitimate conclusion is that these rules were laid down for the guidance of dancers or, perhaps, pantomimes, and with this accords admirably the fact that the dramatic tradition knows nothing of these names, and instead makes the sage Bharata the eponymous hero of the drama. True it was Brahmā, highest of gods, himself who, at the instance of the gods, produced as a counterpart to the four Vedas, which contain the science of religion and magic, the more mundane Nāṭya-Veda, consecrated to the drama, but this Veda is not current among men. Bharata, on the other hand, whose task it was to direct the production by the Apsarases in heaven of plays for the delight of the gods and who thus had practical experience of the art, has set forth for men the principles of the drama in the Nāṭyaçāstra which, if not inspired, has at least a measure of sanctity, and thus supplies an authoritative basis for practice. The legend is interesting because it precisely interprets the spirit of India towards authority; Bharata occupies in the theory of the drama a place analogous to that of Pāṇini in grammar, but unfortunately the Nāṭyaçāstra has fared badly in comparison with the Aṣṭādhyāyī, which has, through the care of its commentators, come down to us in a form but little changed from that it assumed in the hands of its author. The work, which we have under the title Bhāratīya Nāṭyaçāstra, [598] is extremely badly preserved in the manuscript tradition, a fact due in part to the comparatively late date of any commentary upon it. We have only a few references to an exposition of the Nāṭyaçāstra by Mātṛgupta, a somewhat mysterious figure with a more or less legendary connexion with Kālidāsa, with whom he has even been identified; [599] if we are to place any faith in his contemporaneity with Kālidāsa, he may date from the close of the fourth century A.D. It is significant that tradition makes him for a time king of Kashmir, for it is to that country we owe the commentaries of Çan̄kuka, who wrote the epic Bhuvanābhyudaya under Ajitāpīḍa (A.D. 813–50), and of Bhaṭṭa Nāyaka, who belongs to the period of Çan̄karavarman (A.D. 883–902). In the same line of tradition is the great work of Abhinavagupta, the Abhinavabhāratī, which has been lucky enough to come to light after long oblivion, and which represents the erudition of the close of the tenth century.