A type of Kriyā (urge);
a sub-type of Mithyādarśanapratyayā Kriyā (the propensity qua perverted faith), in which the existence of categories of truth (i.e. really existent substances) are not accepted; e.g., (to believe that) there is no soul.
ūnātiriktamithyādarśanād vyatiriktaṃ mithyādarśanaṃ - nāstyevātmetyādimatariipaṃ pratyayo yasyaḥ sā tathā.
(Sthā 2.16 Vr Pa 39)