the imaginative experience of tranquility, emotion of emotionlessness)[1][2] is considered a ninth rasa, a concept of aesthetic flavour in Sanskrit literature.
[3] It has as its stable emotion (sthāyibhāva) impassivity (sama) which culminates in detachment (Vairāgya) arising from knowledge of truth and purity of mind.
The inclusion of this rasa as a prominent one in Sanskrit poetry and dramaturgy is attributed to Udbhata, a president in the court of king Jayapida of Kashmir during 779-813 AD and a contemporary of Vamana.
Kalhaṇa being consistent in providing a factual account of the Kashmiri kings, he invokes the distasteful flavor (vīrarasa) as a subordinate to śāntarasa as the aesthetic goal of his work.
Many commentators argue that portraying such a state of cessation or detachment from all the worldly desires is not possible on the stage, hence it could not be an aesthetic flavor in poetics and dramaturgy.
the rasa of fury or anger, derived via the morphological process of वृद्धि (vṛddhi) from रुद्र (rudra), the name of a Vedic deity, later identified with Shiva (śiva, Sanskrit: शिव), and murder.
Thus, the supporters of śāntarasa as a rasa assert, the aim in a drama is not to present an impossible flavor on this stage, but to portray "ardent spirit in search of truth and tranquility".
[19] According to Sheldon Pollock, a new category in aesthetic flavors was created even though most of the religious poetry was based on the passion and desire of God and not about dispassion.